Merge pull request #1134 from yasu-dev221/fix/openai-compat-prompt-cache-key

fix(openai): add fallback prompt_cache_key for compat codex OAuth requests

.gitattributes

@@ -4,6 +4,13 @@ backend/migrations/*.sql text eol=lf
 # Go 源代码文件
 *.go text eol=lf
 
+# 前端 源代码文件
+*.ts text eol=lf
+*.tsx text eol=lf
+*.js text eol=lf
+*.jsx text eol=lf
+*.vue text eol=lf
+
 # Shell 脚本
 *.sh text eol=lf
 

.github/workflows/release.yml

@@ -271,3 +271,36 @@ jobs:
                 parse_mode: "Markdown",
                 disable_web_page_preview: true
               }')"
+
+  sync-version-file:
+    needs: [release]
+    if: ${{ needs.release.result == 'success' }}
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout default branch
+        uses: actions/checkout@v6
+        with:
+          ref: ${{ github.event.repository.default_branch }}
+
+      - name: Sync VERSION file to released tag
+        run: |
+          if [ "${{ github.event_name }}" = "workflow_dispatch" ]; then
+            VERSION=${{ github.event.inputs.tag }}
+            VERSION=${VERSION#v}
+          else
+            VERSION=${GITHUB_REF#refs/tags/v}
+          fi
+
+          CURRENT_VERSION=$(tr -d '\r\n' < backend/cmd/server/VERSION || true)
+          if [ "$CURRENT_VERSION" = "$VERSION" ]; then
+            echo "VERSION file already matches $VERSION"
+            exit 0
+          fi
+
+          echo "$VERSION" > backend/cmd/server/VERSION
+
+          git config user.name "github-actions[bot]"
+          git config user.email "41898282+github-actions[bot]@users.noreply.github.com"
+          git add backend/cmd/server/VERSION
+          git commit -m "chore: sync VERSION to ${VERSION} [skip ci]"
+          git push origin HEAD:${{ github.event.repository.default_branch }}

.goreleaser.simple.yaml

@@ -47,6 +47,8 @@ dockers:
       - "ghcr.io/{{ .Env.GITHUB_REPO_OWNER_LOWER }}/sub2api:latest"
     dockerfile: Dockerfile.goreleaser
     use: buildx
+    extra_files:
+      - deploy/docker-entrypoint.sh
     build_flag_templates:
       - "--platform=linux/amd64"
       - "--label=org.opencontainers.image.version={{ .Version }}"

.goreleaser.yaml

@@ -63,6 +63,8 @@ dockers:
       - "{{ .Env.DOCKERHUB_USERNAME }}/sub2api:{{ .Version }}-amd64"
     dockerfile: Dockerfile.goreleaser
     use: buildx
+    extra_files:
+      - deploy/docker-entrypoint.sh
     build_flag_templates:
       - "--platform=linux/amd64"
       - "--label=org.opencontainers.image.version={{ .Version }}"
@@ -76,6 +78,8 @@ dockers:
       - "{{ .Env.DOCKERHUB_USERNAME }}/sub2api:{{ .Version }}-arm64"
     dockerfile: Dockerfile.goreleaser
     use: buildx
+    extra_files:
+      - deploy/docker-entrypoint.sh
     build_flag_templates:
       - "--platform=linux/arm64"
       - "--label=org.opencontainers.image.version={{ .Version }}"
@@ -89,6 +93,8 @@ dockers:
       - "ghcr.io/{{ .Env.GITHUB_REPO_OWNER_LOWER }}/sub2api:{{ .Version }}-amd64"
     dockerfile: Dockerfile.goreleaser
     use: buildx
+    extra_files:
+      - deploy/docker-entrypoint.sh
     build_flag_templates:
       - "--platform=linux/amd64"
       - "--label=org.opencontainers.image.version={{ .Version }}"
@@ -102,6 +108,8 @@ dockers:
       - "ghcr.io/{{ .Env.GITHUB_REPO_OWNER_LOWER }}/sub2api:{{ .Version }}-arm64"
     dockerfile: Dockerfile.goreleaser
     use: buildx
+    extra_files:
+      - deploy/docker-entrypoint.sh
     build_flag_templates:
       - "--platform=linux/arm64"
       - "--label=org.opencontainers.image.version={{ .Version }}"

Dockerfile

@@ -9,6 +9,7 @@
 ARG NODE_IMAGE=node:24-alpine
 ARG GOLANG_IMAGE=golang:1.26.1-alpine
 ARG ALPINE_IMAGE=alpine:3.21
+ARG POSTGRES_IMAGE=postgres:18-alpine
 ARG GOPROXY=https://goproxy.cn,direct
 ARG GOSUMDB=sum.golang.google.cn
 
@@ -73,7 +74,12 @@ RUN VERSION_VALUE="${VERSION}" && \
     ./cmd/server
 
 # -----------------------------------------------------------------------------
-# Stage 3: Final Runtime Image
+# Stage 3: PostgreSQL Client (version-matched with docker-compose)
+# -----------------------------------------------------------------------------
+FROM ${POSTGRES_IMAGE} AS pg-client
+
+# -----------------------------------------------------------------------------
+# Stage 4: Final Runtime Image
 # -----------------------------------------------------------------------------
 FROM ${ALPINE_IMAGE}
 
@@ -86,8 +92,21 @@ LABEL org.opencontainers.image.source="https://github.com/Wei-Shaw/sub2api"
 RUN apk add --no-cache \
     ca-certificates \
     tzdata \
+    su-exec \
+    libpq \
+    zstd-libs \
+    lz4-libs \
+    krb5-libs \
+    libldap \
+    libedit \
     && rm -rf /var/cache/apk/*
 
+# Copy pg_dump and psql from the same postgres image used in docker-compose
+# This ensures version consistency between backup tools and the database server
+COPY --from=pg-client /usr/local/bin/pg_dump /usr/local/bin/pg_dump
+COPY --from=pg-client /usr/local/bin/psql /usr/local/bin/psql
+COPY --from=pg-client /usr/local/lib/libpq.so.5* /usr/local/lib/
+
 # Create non-root user
 RUN addgroup -g 1000 sub2api && \
     adduser -u 1000 -G sub2api -s /bin/sh -D sub2api
@@ -102,8 +121,9 @@ COPY --from=backend-builder --chown=sub2api:sub2api /app/backend/resources /app/
 # Create data directory
 RUN mkdir -p /app/data && chown sub2api:sub2api /app/data
 
-# Switch to non-root user
-USER sub2api
+# Copy entrypoint script (fixes volume permissions then drops to sub2api)
+COPY deploy/docker-entrypoint.sh /app/docker-entrypoint.sh
+RUN chmod +x /app/docker-entrypoint.sh
 
 # Expose port (can be overridden by SERVER_PORT env var)
 EXPOSE 8080
@@ -112,5 +132,6 @@ EXPOSE 8080
 HEALTHCHECK --interval=30s --timeout=10s --start-period=10s --retries=3 \
     CMD wget -q -T 5 -O /dev/null http://localhost:${SERVER_PORT:-8080}/health || exit 1
 
-# Run the application
-ENTRYPOINT ["/app/sub2api"]
+# Run the application (entrypoint fixes /app/data ownership then execs as sub2api)
+ENTRYPOINT ["/app/docker-entrypoint.sh"]
+CMD ["/app/sub2api"]

Dockerfile.goreleaser

@@ -5,7 +5,12 @@
 # It only packages the pre-built binary, no compilation needed.
 # =============================================================================
 
-FROM alpine:3.19
+ARG ALPINE_IMAGE=alpine:3.21
+ARG POSTGRES_IMAGE=postgres:18-alpine
+
+FROM ${POSTGRES_IMAGE} AS pg-client
+
+FROM ${ALPINE_IMAGE}
 
 LABEL maintainer="Wei-Shaw <github.com/Wei-Shaw>"
 LABEL description="Sub2API - AI API Gateway Platform"
@@ -16,8 +21,21 @@ RUN apk add --no-cache \
     ca-certificates \
     tzdata \
     curl \
+    su-exec \
+    libpq \
+    zstd-libs \
+    lz4-libs \
+    krb5-libs \
+    libldap \
+    libedit \
     && rm -rf /var/cache/apk/*
 
+# Copy pg_dump and psql from a version-matched PostgreSQL image so backup and
+# restore work in the runtime container without requiring Docker socket access.
+COPY --from=pg-client /usr/local/bin/pg_dump /usr/local/bin/pg_dump
+COPY --from=pg-client /usr/local/bin/psql /usr/local/bin/psql
+COPY --from=pg-client /usr/local/lib/libpq.so.5* /usr/local/lib/
+
 # Create non-root user
 RUN addgroup -g 1000 sub2api && \
     adduser -u 1000 -G sub2api -s /bin/sh -D sub2api
@@ -30,11 +48,15 @@ COPY sub2api /app/sub2api
 # Create data directory
 RUN mkdir -p /app/data && chown -R sub2api:sub2api /app
 
-USER sub2api
+# Copy entrypoint script (fixes volume permissions then drops to sub2api)
+COPY deploy/docker-entrypoint.sh /app/docker-entrypoint.sh
+RUN chmod +x /app/docker-entrypoint.sh
 
 EXPOSE 8080
 
 HEALTHCHECK --interval=30s --timeout=10s --start-period=10s --retries=3 \
     CMD curl -f http://localhost:${SERVER_PORT:-8080}/health || exit 1
 
-ENTRYPOINT ["/app/sub2api"]
+# Run the application (entrypoint fixes /app/data ownership then execs as sub2api)
+ENTRYPOINT ["/app/docker-entrypoint.sh"]
+CMD ["/app/sub2api"]

README.md

@@ -8,27 +8,31 @@
 [![Redis](https://img.shields.io/badge/Redis-7+-DC382D.svg)](https://redis.io/)
 [![Docker](https://img.shields.io/badge/Docker-Ready-2496ED.svg)](https://www.docker.com/)
 
+<a href="https://trendshift.io/repositories/21823" target="_blank"><img src="https://trendshift.io/api/badge/repositories/21823" alt="Wei-Shaw%2Fsub2api | Trendshift" width="250" height="55"/></a>
+
 **AI API Gateway Platform for Subscription Quota Distribution**
 
 English | [中文](README_CN.md)
 
 </div>
 
+> **Sub2API officially uses only the domains `sub2api.org` and `pincc.ai`. Other websites using the Sub2API name may be third-party deployments or services and are not affiliated with this project. Please verify and exercise your own judgment.**
+
 ---
 
 ## Demo
 
-Try Sub2API online: **https://demo.sub2api.org/**
+Try Sub2API online: **[https://demo.sub2api.org/](https://demo.sub2api.org/)**
 
 Demo credentials (shared demo environment; **not** created automatically for self-hosted installs):
 
 | Email | Password |
 |-------|----------|
-| admin@sub2api.com | admin123 |
+| admin@sub2api.org | admin123 |
 
 ## Overview
 
-Sub2API is an AI API gateway platform designed to distribute and manage API quotas from AI product subscriptions (like Claude Code $200/month). Users can access upstream AI services through platform-generated API Keys, while the platform handles authentication, billing, load balancing, and request forwarding.
+Sub2API is an AI API gateway platform designed to distribute and manage API quotas from AI product subscriptions. Users can access upstream AI services through platform-generated API Keys, while the platform handles authentication, billing, load balancing, and request forwarding.
 
 ## Features
 
@@ -39,6 +43,25 @@ Sub2API is an AI API gateway platform designed to distribute and manage API quot
 - **Concurrency Control** - Per-user and per-account concurrency limits
 - **Rate Limiting** - Configurable request and token rate limits
 - **Admin Dashboard** - Web interface for monitoring and management
+- **External System Integration** - Embed external systems (e.g. payment, ticketing) via iframe to extend the admin dashboard
+
+## Don't Want to Self-Host?
+
+<table>
+<tr>
+<td width="180" align="center" valign="middle"><a href="https://shop.pincc.ai/"><img src="assets/partners/logos/pincc-logo.png" alt="pincc" width="120"></a></td>
+<td valign="middle"><b><a href="https://shop.pincc.ai/">PinCC</a></b> is the official relay service built on Sub2API, offering stable access to Claude Code, Codex, Gemini and other popular models — ready to use, no deployment or maintenance required.</td>
+</tr>
+</table>
+
+## Ecosystem
+
+Community projects that extend or integrate with Sub2API:
+
+| Project | Description | Features |
+|---------|-------------|----------|
+| [Sub2ApiPay](https://github.com/touwaeriol/sub2apipay) | Self-service payment system | Self-service top-up and subscription purchase; supports YiPay protocol, WeChat Pay, Alipay, Stripe; embeddable via iframe |
+| [sub2api-mobile](https://github.com/ckken/sub2api-mobile) | Mobile admin console | Cross-platform app (iOS/Android/Web) for user management, account management, monitoring dashboard, and multi-backend switching; built with Expo + React Native |
 
 ## Tech Stack
 
@@ -51,10 +74,15 @@ Sub2API is an AI API gateway platform designed to distribute and manage API quot
 
 ---
 
-## Documentation
+## Nginx Reverse Proxy Note
 
-- Dependency Security: `docs/dependency-security.md`
-- Admin Payment Integration API: `docs/ADMIN_PAYMENT_INTEGRATION_API.md`
+When using Nginx as a reverse proxy for Sub2API (or CRS) with Codex CLI, add the following to the `http` block in your Nginx configuration:
+
+```nginx
+underscores_in_headers on;
+```
+
+Nginx drops headers containing underscores by default (e.g. `session_id`), which breaks sticky session routing in multi-account setups.
 
 ---
 

README_CN.md

@@ -8,27 +8,30 @@
 [![Redis](https://img.shields.io/badge/Redis-7+-DC382D.svg)](https://redis.io/)
 [![Docker](https://img.shields.io/badge/Docker-Ready-2496ED.svg)](https://www.docker.com/)
 
+<a href="https://trendshift.io/repositories/21823" target="_blank"><img src="https://trendshift.io/api/badge/repositories/21823" alt="Wei-Shaw%2Fsub2api | Trendshift" width="250" height="55"/></a>
+
 **AI API 网关平台 - 订阅配额分发管理**
 
 [English](README.md) | 中文
 
 </div>
 
+> **Sub2API 官方仅使用  `sub2api.org` 与 `pincc.ai` 两个域名。其他使用 Sub2API 名义的网站可能为第三方部署或服务，与本项目无关，请自行甄别。**
 ---
 
 ## 在线体验
 
-体验地址：**https://v2.pincc.ai/**
+体验地址：**[https://demo.sub2api.org/](https://demo.sub2api.org/)**
 
 演示账号（共享演示环境；自建部署不会自动创建该账号）：
 
 | 邮箱 | 密码 |
 |------|------|
-| admin@sub2api.com | admin123 |
+| admin@sub2api.org | admin123 |
 
 ## 项目概述
 
-Sub2API 是一个 AI API 网关平台，用于分发和管理 AI 产品订阅（如 Claude Code $200/月）的 API 配额。用户通过平台生成的 API Key 调用上游 AI 服务，平台负责鉴权、计费、负载均衡和请求转发。
+Sub2API 是一个 AI API 网关平台，用于分发和管理 AI 产品订阅的 API 配额。用户通过平台生成的 API Key 调用上游 AI 服务，平台负责鉴权、计费、负载均衡和请求转发。
 
 ## 核心功能
 
@@ -39,6 +42,25 @@ Sub2API 是一个 AI API 网关平台，用于分发和管理 AI 产品订阅（
 - **并发控制** - 用户级和账号级并发限制
 - **速率限制** - 可配置的请求和 Token 速率限制
 - **管理后台** - Web 界面进行监控和管理
+- **外部系统集成** - 支持通过 iframe 嵌入外部系统（如支付、工单等），扩展管理后台功能
+
+## 不想自建？试试官方中转
+
+<table>
+<tr>
+<td width="180" align="center" valign="middle"><a href="https://shop.pincc.ai/"><img src="assets/partners/logos/pincc-logo.png" alt="pincc" width="120"></a></td>
+<td valign="middle"><b><a href="https://shop.pincc.ai/">PinCC</a></b> 是基于 Sub2API 搭建的官方中转服务，提供 Claude Code、Codex、Gemini 等主流模型的稳定中转，开箱即用，免去自建部署与运维烦恼。</td>
+</tr>
+</table>
+
+## 生态项目
+
+围绕 Sub2API 的社区扩展与集成项目：
+
+| 项目 | 说明 | 功能 |
+|------|------|------|
+| [Sub2ApiPay](https://github.com/touwaeriol/sub2apipay) | 自助支付系统 | 用户自助充值、自助订阅购买；兼容易支付协议、微信官方支付、支付宝官方支付、Stripe；支持 iframe 嵌入管理后台 |
+| [sub2api-mobile](https://github.com/ckken/sub2api-mobile) | 移动端管理控制台 | 跨平台应用（iOS/Android/Web），支持用户管理、账号管理、监控看板、多后端切换；基于 Expo + React Native 构建 |
 
 ## 技术栈
 
@@ -51,17 +73,18 @@ Sub2API 是一个 AI API 网关平台，用于分发和管理 AI 产品订阅（
 
 ---
 
-## 文档
+## Nginx 反向代理注意事项
 
-- 依赖安全：`docs/dependency-security.md`
+通过 Nginx 反向代理 Sub2API（或 CRS 服务）并搭配 Codex CLI 使用时，需要在 Nginx 配置的 `http` 块中添加：
+
+```nginx
+underscores_in_headers on;
+```
+
+Nginx 默认会丢弃名称中含下划线的请求头（如 `session_id`），这会导致多账号环境下的粘性会话功能失效。
 
 ---
 
-## OpenAI Responses 兼容注意事项
-
-- 当请求包含 `function_call_output` 时，需要携带 `previous_response_id`，或在 `input` 中包含带 `call_id` 的 `tool_call`/`function_call`，或带非空 `id` 且与 `function_call_output.call_id` 匹配的 `item_reference`。
-- 若依赖上游历史记录，网关会强制 `store=true` 并需要复用 `previous_response_id`，以避免出现 “No tool call found for function call output” 错误。
-
 ## 部署方式
 
 ### 方式一：脚本安装（推荐）

backend/cmd/server/wire.go

@@ -41,6 +41,9 @@ func initializeApplication(buildInfo handler.BuildInfo) (*Application, error) {
 		// Server layer ProviderSet
 		server.ProviderSet,
 
+		// Privacy client factory for OpenAI training opt-out
+		providePrivacyClientFactory,
+
 		// BuildInfo provider
 		provideServiceBuildInfo,
 
@@ -53,6 +56,10 @@ func initializeApplication(buildInfo handler.BuildInfo) (*Application, error) {
 	return nil, nil
 }
 
+func providePrivacyClientFactory() service.PrivacyClientFactory {
+	return repository.CreatePrivacyReqClient
+}
+
 func provideServiceBuildInfo(buildInfo handler.BuildInfo) service.BuildInfo {
 	return service.BuildInfo{
 		Version:   buildInfo.Version,
@@ -87,6 +94,7 @@ func provideCleanup(
 	antigravityOAuth *service.AntigravityOAuthService,
 	openAIGateway *service.OpenAIGatewayService,
 	scheduledTestRunner *service.ScheduledTestRunnerService,
+	backupSvc *service.BackupService,
 ) func() {
 	return func() {
 		ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
@@ -223,6 +231,12 @@ func provideCleanup(
 				}
 				return nil
 			}},
+			{"BackupService", func() error {
+				if backupSvc != nil {
+					backupSvc.Stop()
+				}
+				return nil
+			}},
 		}
 
 		infraSteps := []cleanupStep{

backend/cmd/server/wire_gen.go

@@ -81,6 +81,7 @@ func initializeApplication(buildInfo handler.BuildInfo) (*Application, error) {
 	userHandler := handler.NewUserHandler(userService)
 	apiKeyHandler := handler.NewAPIKeyHandler(apiKeyService)
 	usageLogRepository := repository.NewUsageLogRepository(client, db)
+	usageBillingRepository := repository.NewUsageBillingRepository(client, db)
 	usageService := service.NewUsageService(usageLogRepository, userRepository, client, apiKeyAuthCacheInvalidator)
 	usageHandler := handler.NewUsageHandler(usageService, apiKeyService)
 	redeemHandler := handler.NewRedeemHandler(redeemService)
@@ -104,11 +105,11 @@ func initializeApplication(buildInfo handler.BuildInfo) (*Application, error) {
 	proxyRepository := repository.NewProxyRepository(client, db)
 	proxyExitInfoProber := repository.NewProxyExitInfoProber(configConfig)
 	proxyLatencyCache := repository.NewProxyLatencyCache(redisClient)
-	adminService := service.NewAdminService(userRepository, groupRepository, accountRepository, soraAccountRepository, proxyRepository, apiKeyRepository, redeemCodeRepository, userGroupRateRepository, billingCacheService, proxyExitInfoProber, proxyLatencyCache, apiKeyAuthCacheInvalidator, client, settingService, subscriptionService, userSubscriptionRepository)
+	privacyClientFactory := providePrivacyClientFactory()
+	adminService := service.NewAdminService(userRepository, groupRepository, accountRepository, soraAccountRepository, proxyRepository, apiKeyRepository, redeemCodeRepository, userGroupRateRepository, billingCacheService, proxyExitInfoProber, proxyLatencyCache, apiKeyAuthCacheInvalidator, client, settingService, subscriptionService, userSubscriptionRepository, privacyClientFactory)
 	concurrencyCache := repository.ProvideConcurrencyCache(redisClient, configConfig)
 	concurrencyService := service.ProvideConcurrencyService(concurrencyCache, accountRepository, configConfig)
 	adminUserHandler := admin.NewUserHandler(adminService, concurrencyService)
-	groupHandler := admin.NewGroupHandler(adminService)
 	claudeOAuthClient := repository.NewClaudeOAuthClient()
 	oAuthService := service.NewOAuthService(proxyRepository, claudeOAuthClient)
 	openAIOAuthClient := repository.NewOpenAIOAuthClient()
@@ -122,6 +123,7 @@ func initializeApplication(buildInfo handler.BuildInfo) (*Application, error) {
 	tempUnschedCache := repository.NewTempUnschedCache(redisClient)
 	timeoutCounterCache := repository.NewTimeoutCounterCache(redisClient)
 	geminiTokenCache := repository.NewGeminiTokenCache(redisClient)
+	oauthRefreshAPI := service.NewOAuthRefreshAPI(accountRepository, geminiTokenCache)
 	compositeTokenCacheInvalidator := service.NewCompositeTokenCacheInvalidator(geminiTokenCache)
 	rateLimitService := service.ProvideRateLimitService(accountRepository, usageLogRepository, configConfig, geminiQuotaService, tempUnschedCache, timeoutCounterCache, settingService, compositeTokenCacheInvalidator)
 	httpUpstream := repository.NewHTTPUpstream(configConfig)
@@ -130,20 +132,26 @@ func initializeApplication(buildInfo handler.BuildInfo) (*Application, error) {
 	usageCache := service.NewUsageCache()
 	identityCache := repository.NewIdentityCache(redisClient)
 	accountUsageService := service.NewAccountUsageService(accountRepository, usageLogRepository, claudeUsageFetcher, geminiQuotaService, antigravityQuotaFetcher, usageCache, identityCache)
-	geminiTokenProvider := service.NewGeminiTokenProvider(accountRepository, geminiTokenCache, geminiOAuthService)
+	geminiTokenProvider := service.ProvideGeminiTokenProvider(accountRepository, geminiTokenCache, geminiOAuthService, oauthRefreshAPI)
 	gatewayCache := repository.NewGatewayCache(redisClient)
 	schedulerOutboxRepository := repository.NewSchedulerOutboxRepository(db)
 	schedulerSnapshotService := service.ProvideSchedulerSnapshotService(schedulerCache, schedulerOutboxRepository, accountRepository, groupRepository, configConfig)
-	antigravityTokenProvider := service.NewAntigravityTokenProvider(accountRepository, geminiTokenCache, antigravityOAuthService)
+	antigravityTokenProvider := service.ProvideAntigravityTokenProvider(accountRepository, geminiTokenCache, antigravityOAuthService, oauthRefreshAPI)
 	antigravityGatewayService := service.NewAntigravityGatewayService(accountRepository, gatewayCache, schedulerSnapshotService, antigravityTokenProvider, rateLimitService, httpUpstream, settingService)
 	accountTestService := service.NewAccountTestService(accountRepository, geminiTokenProvider, antigravityGatewayService, httpUpstream, configConfig)
 	crsSyncService := service.NewCRSSyncService(accountRepository, proxyRepository, oAuthService, openAIOAuthService, geminiOAuthService, configConfig)
 	sessionLimitCache := repository.ProvideSessionLimitCache(redisClient, configConfig)
 	rpmCache := repository.NewRPMCache(redisClient)
+	groupCapacityService := service.NewGroupCapacityService(accountRepository, groupRepository, concurrencyService, sessionLimitCache, rpmCache)
+	groupHandler := admin.NewGroupHandler(adminService, dashboardService, groupCapacityService)
 	accountHandler := admin.NewAccountHandler(adminService, oAuthService, openAIOAuthService, geminiOAuthService, antigravityOAuthService, rateLimitService, accountUsageService, accountTestService, concurrencyService, crsSyncService, sessionLimitCache, rpmCache, compositeTokenCacheInvalidator)
 	adminAnnouncementHandler := admin.NewAnnouncementHandler(announcementService)
 	dataManagementService := service.NewDataManagementService()
 	dataManagementHandler := admin.NewDataManagementHandler(dataManagementService)
+	backupObjectStoreFactory := repository.NewS3BackupStoreFactory()
+	dbDumper := repository.NewPgDumper(configConfig)
+	backupService := service.ProvideBackupService(settingRepository, configConfig, secretEncryptor, backupObjectStoreFactory, dbDumper)
+	backupHandler := admin.NewBackupHandler(backupService, userService)
 	oAuthHandler := admin.NewOAuthHandler(oAuthService)
 	openAIOAuthHandler := admin.NewOpenAIOAuthHandler(openAIOAuthService, adminService)
 	geminiOAuthHandler := admin.NewGeminiOAuthHandler(geminiOAuthService)
@@ -160,11 +168,11 @@ func initializeApplication(buildInfo handler.BuildInfo) (*Application, error) {
 	billingService := service.NewBillingService(configConfig, pricingService)
 	identityService := service.NewIdentityService(identityCache)
 	deferredService := service.ProvideDeferredService(accountRepository, timingWheelService)
-	claudeTokenProvider := service.NewClaudeTokenProvider(accountRepository, geminiTokenCache, oAuthService)
+	claudeTokenProvider := service.ProvideClaudeTokenProvider(accountRepository, geminiTokenCache, oAuthService, oauthRefreshAPI)
 	digestSessionStore := service.NewDigestSessionStore()
-	gatewayService := service.NewGatewayService(accountRepository, groupRepository, usageLogRepository, userRepository, userSubscriptionRepository, userGroupRateRepository, gatewayCache, configConfig, schedulerSnapshotService, concurrencyService, billingService, rateLimitService, billingCacheService, identityService, httpUpstream, deferredService, claudeTokenProvider, sessionLimitCache, rpmCache, digestSessionStore, settingService)
-	openAITokenProvider := service.NewOpenAITokenProvider(accountRepository, geminiTokenCache, openAIOAuthService)
-	openAIGatewayService := service.NewOpenAIGatewayService(accountRepository, usageLogRepository, userRepository, userSubscriptionRepository, userGroupRateRepository, gatewayCache, configConfig, schedulerSnapshotService, concurrencyService, billingService, rateLimitService, billingCacheService, httpUpstream, deferredService, openAITokenProvider)
+	gatewayService := service.NewGatewayService(accountRepository, groupRepository, usageLogRepository, usageBillingRepository, userRepository, userSubscriptionRepository, userGroupRateRepository, gatewayCache, configConfig, schedulerSnapshotService, concurrencyService, billingService, rateLimitService, billingCacheService, identityService, httpUpstream, deferredService, claudeTokenProvider, sessionLimitCache, rpmCache, digestSessionStore, settingService)
+	openAITokenProvider := service.ProvideOpenAITokenProvider(accountRepository, geminiTokenCache, openAIOAuthService, oauthRefreshAPI)
+	openAIGatewayService := service.NewOpenAIGatewayService(accountRepository, usageLogRepository, usageBillingRepository, userRepository, userSubscriptionRepository, userGroupRateRepository, gatewayCache, configConfig, schedulerSnapshotService, concurrencyService, billingService, rateLimitService, billingCacheService, httpUpstream, deferredService, openAITokenProvider)
 	geminiMessagesCompatService := service.NewGeminiMessagesCompatService(accountRepository, groupRepository, gatewayCache, schedulerSnapshotService, geminiTokenProvider, rateLimitService, httpUpstream, antigravityGatewayService, configConfig)
 	opsSystemLogSink := service.ProvideOpsSystemLogSink(opsRepository)
 	opsService := service.NewOpsService(opsRepository, settingRepository, configConfig, accountRepository, userRepository, concurrencyService, gatewayService, openAIGatewayService, geminiMessagesCompatService, antigravityGatewayService, opsSystemLogSink)
@@ -199,7 +207,7 @@ func initializeApplication(buildInfo handler.BuildInfo) (*Application, error) {
 	scheduledTestResultRepository := repository.NewScheduledTestResultRepository(db)
 	scheduledTestService := service.ProvideScheduledTestService(scheduledTestPlanRepository, scheduledTestResultRepository)
 	scheduledTestHandler := admin.NewScheduledTestHandler(scheduledTestService)
-	adminHandlers := handler.ProvideAdminHandlers(dashboardHandler, adminUserHandler, groupHandler, accountHandler, adminAnnouncementHandler, dataManagementHandler, oAuthHandler, openAIOAuthHandler, geminiOAuthHandler, antigravityOAuthHandler, proxyHandler, adminRedeemHandler, promoHandler, settingHandler, opsHandler, systemHandler, adminSubscriptionHandler, adminUsageHandler, userAttributeHandler, errorPassthroughHandler, adminAPIKeyHandler, scheduledTestHandler)
+	adminHandlers := handler.ProvideAdminHandlers(dashboardHandler, adminUserHandler, groupHandler, accountHandler, adminAnnouncementHandler, dataManagementHandler, backupHandler, oAuthHandler, openAIOAuthHandler, geminiOAuthHandler, antigravityOAuthHandler, proxyHandler, adminRedeemHandler, promoHandler, settingHandler, opsHandler, systemHandler, adminSubscriptionHandler, adminUsageHandler, userAttributeHandler, errorPassthroughHandler, adminAPIKeyHandler, scheduledTestHandler)
 	usageRecordWorkerPool := service.NewUsageRecordWorkerPool(configConfig)
 	userMsgQueueCache := repository.NewUserMsgQueueCache(redisClient)
 	userMessageQueueService := service.ProvideUserMessageQueueService(userMsgQueueCache, rpmCache, configConfig)
@@ -226,11 +234,11 @@ func initializeApplication(buildInfo handler.BuildInfo) (*Application, error) {
 	opsCleanupService := service.ProvideOpsCleanupService(opsRepository, db, redisClient, configConfig)
 	opsScheduledReportService := service.ProvideOpsScheduledReportService(opsService, userService, emailService, redisClient, configConfig)
 	soraMediaCleanupService := service.ProvideSoraMediaCleanupService(soraMediaStorage, configConfig)
-	tokenRefreshService := service.ProvideTokenRefreshService(accountRepository, soraAccountRepository, oAuthService, openAIOAuthService, geminiOAuthService, antigravityOAuthService, compositeTokenCacheInvalidator, schedulerCache, configConfig, tempUnschedCache)
+	tokenRefreshService := service.ProvideTokenRefreshService(accountRepository, soraAccountRepository, oAuthService, openAIOAuthService, geminiOAuthService, antigravityOAuthService, compositeTokenCacheInvalidator, schedulerCache, configConfig, tempUnschedCache, privacyClientFactory, proxyRepository, oauthRefreshAPI)
 	accountExpiryService := service.ProvideAccountExpiryService(accountRepository)
 	subscriptionExpiryService := service.ProvideSubscriptionExpiryService(userSubscriptionRepository)
 	scheduledTestRunnerService := service.ProvideScheduledTestRunnerService(scheduledTestPlanRepository, scheduledTestService, accountTestService, rateLimitService, configConfig)
-	v := provideCleanup(client, redisClient, opsMetricsCollector, opsAggregationService, opsAlertEvaluatorService, opsCleanupService, opsScheduledReportService, opsSystemLogSink, soraMediaCleanupService, schedulerSnapshotService, tokenRefreshService, accountExpiryService, subscriptionExpiryService, usageCleanupService, idempotencyCleanupService, pricingService, emailQueueService, billingCacheService, usageRecordWorkerPool, subscriptionService, oAuthService, openAIOAuthService, geminiOAuthService, antigravityOAuthService, openAIGatewayService, scheduledTestRunnerService)
+	v := provideCleanup(client, redisClient, opsMetricsCollector, opsAggregationService, opsAlertEvaluatorService, opsCleanupService, opsScheduledReportService, opsSystemLogSink, soraMediaCleanupService, schedulerSnapshotService, tokenRefreshService, accountExpiryService, subscriptionExpiryService, usageCleanupService, idempotencyCleanupService, pricingService, emailQueueService, billingCacheService, usageRecordWorkerPool, subscriptionService, oAuthService, openAIOAuthService, geminiOAuthService, antigravityOAuthService, openAIGatewayService, scheduledTestRunnerService, backupService)
 	application := &Application{
 		Server:  httpServer,
 		Cleanup: v,
@@ -245,6 +253,10 @@ type Application struct {
 	Cleanup func()
 }
 
+func providePrivacyClientFactory() service.PrivacyClientFactory {
+	return repository.CreatePrivacyReqClient
+}
+
 func provideServiceBuildInfo(buildInfo handler.BuildInfo) service.BuildInfo {
 	return service.BuildInfo{
 		Version:   buildInfo.Version,
@@ -279,6 +291,7 @@ func provideCleanup(
 	antigravityOAuth *service.AntigravityOAuthService,
 	openAIGateway *service.OpenAIGatewayService,
 	scheduledTestRunner *service.ScheduledTestRunnerService,
+	backupSvc *service.BackupService,
 ) func() {
 	return func() {
 		ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
@@ -414,6 +427,12 @@ func provideCleanup(
 				}
 				return nil
 			}},
+			{"BackupService", func() error {
+				if backupSvc != nil {
+					backupSvc.Stop()
+				}
+				return nil
+			}},
 		}
 
 		infraSteps := []cleanupStep{

backend/cmd/server/wire_gen_test.go

@@ -75,6 +75,7 @@ func TestProvideCleanup_WithMinimalDependencies_NoPanic(t *testing.T) {
 		antigravityOAuthSvc,
 		nil, // openAIGateway
 		nil, // scheduledTestRunner
+		nil, // backupSvc
 	)
 
 	require.NotPanics(t, func() {

backend/ent/migrate/schema.go

@@ -716,6 +716,7 @@ var (
 		{Name: "id", Type: field.TypeInt64, Increment: true},
 		{Name: "request_id", Type: field.TypeString, Size: 64},
 		{Name: "model", Type: field.TypeString, Size: 100},
+		{Name: "upstream_model", Type: field.TypeString, Nullable: true, Size: 100},
 		{Name: "input_tokens", Type: field.TypeInt, Default: 0},
 		{Name: "output_tokens", Type: field.TypeInt, Default: 0},
 		{Name: "cache_creation_tokens", Type: field.TypeInt, Default: 0},
@@ -755,31 +756,31 @@ var (
 		ForeignKeys: []*schema.ForeignKey{
 			{
 				Symbol:     "usage_logs_api_keys_usage_logs",
-				Columns:    []*schema.Column{UsageLogsColumns[28]},
+				Columns:    []*schema.Column{UsageLogsColumns[29]},
 				RefColumns: []*schema.Column{APIKeysColumns[0]},
 				OnDelete:   schema.NoAction,
 			},
 			{
 				Symbol:     "usage_logs_accounts_usage_logs",
-				Columns:    []*schema.Column{UsageLogsColumns[29]},
+				Columns:    []*schema.Column{UsageLogsColumns[30]},
 				RefColumns: []*schema.Column{AccountsColumns[0]},
 				OnDelete:   schema.NoAction,
 			},
 			{
 				Symbol:     "usage_logs_groups_usage_logs",
-				Columns:    []*schema.Column{UsageLogsColumns[30]},
+				Columns:    []*schema.Column{UsageLogsColumns[31]},
 				RefColumns: []*schema.Column{GroupsColumns[0]},
 				OnDelete:   schema.SetNull,
 			},
 			{
 				Symbol:     "usage_logs_users_usage_logs",
-				Columns:    []*schema.Column{UsageLogsColumns[31]},
+				Columns:    []*schema.Column{UsageLogsColumns[32]},
 				RefColumns: []*schema.Column{UsersColumns[0]},
 				OnDelete:   schema.NoAction,
 			},
 			{
 				Symbol:     "usage_logs_user_subscriptions_usage_logs",
-				Columns:    []*schema.Column{UsageLogsColumns[32]},
+				Columns:    []*schema.Column{UsageLogsColumns[33]},
 				RefColumns: []*schema.Column{UserSubscriptionsColumns[0]},
 				OnDelete:   schema.SetNull,
 			},
@@ -788,32 +789,32 @@ var (
 			{
 				Name:    "usagelog_user_id",
 				Unique:  false,
-				Columns: []*schema.Column{UsageLogsColumns[31]},
+				Columns: []*schema.Column{UsageLogsColumns[32]},
 			},
 			{
 				Name:    "usagelog_api_key_id",
 				Unique:  false,
-				Columns: []*schema.Column{UsageLogsColumns[28]},
+				Columns: []*schema.Column{UsageLogsColumns[29]},
 			},
 			{
 				Name:    "usagelog_account_id",
 				Unique:  false,
-				Columns: []*schema.Column{UsageLogsColumns[29]},
+				Columns: []*schema.Column{UsageLogsColumns[30]},
 			},
 			{
 				Name:    "usagelog_group_id",
 				Unique:  false,
-				Columns: []*schema.Column{UsageLogsColumns[30]},
+				Columns: []*schema.Column{UsageLogsColumns[31]},
 			},
 			{
 				Name:    "usagelog_subscription_id",
 				Unique:  false,
-				Columns: []*schema.Column{UsageLogsColumns[32]},
+				Columns: []*schema.Column{UsageLogsColumns[33]},
 			},
 			{
 				Name:    "usagelog_created_at",
 				Unique:  false,
-				Columns: []*schema.Column{UsageLogsColumns[27]},
+				Columns: []*schema.Column{UsageLogsColumns[28]},
 			},
 			{
 				Name:    "usagelog_model",
@@ -828,17 +829,17 @@ var (
 			{
 				Name:    "usagelog_user_id_created_at",
 				Unique:  false,
-				Columns: []*schema.Column{UsageLogsColumns[31], UsageLogsColumns[27]},
+				Columns: []*schema.Column{UsageLogsColumns[32], UsageLogsColumns[28]},
 			},
 			{
 				Name:    "usagelog_api_key_id_created_at",
 				Unique:  false,
-				Columns: []*schema.Column{UsageLogsColumns[28], UsageLogsColumns[27]},
+				Columns: []*schema.Column{UsageLogsColumns[29], UsageLogsColumns[28]},
 			},
 			{
 				Name:    "usagelog_group_id_created_at",
 				Unique:  false,
-				Columns: []*schema.Column{UsageLogsColumns[30], UsageLogsColumns[27]},
+				Columns: []*schema.Column{UsageLogsColumns[31], UsageLogsColumns[28]},
 			},
 		},
 	}

backend/ent/mutation.go

@@ -18239,6 +18239,7 @@ type UsageLogMutation struct {
 	id                          *int64
 	request_id                  *string
 	model                       *string
+	upstream_model              *string
 	input_tokens                *int
 	addinput_tokens             *int
 	output_tokens               *int
@@ -18576,6 +18577,55 @@ func (m *UsageLogMutation) ResetModel() {
 	m.model = nil
 }
 
+// SetUpstreamModel sets the "upstream_model" field.
+func (m *UsageLogMutation) SetUpstreamModel(s string) {
+	m.upstream_model = &s
+}
+
+// UpstreamModel returns the value of the "upstream_model" field in the mutation.
+func (m *UsageLogMutation) UpstreamModel() (r string, exists bool) {
+	v := m.upstream_model
+	if v == nil {
+		return
+	}
+	return *v, true
+}
+
+// OldUpstreamModel returns the old "upstream_model" field's value of the UsageLog entity.
+// If the UsageLog object wasn't provided to the builder, the object is fetched from the database.
+// An error is returned if the mutation operation is not UpdateOne, or the database query fails.
+func (m *UsageLogMutation) OldUpstreamModel(ctx context.Context) (v *string, err error) {
+	if !m.op.Is(OpUpdateOne) {
+		return v, errors.New("OldUpstreamModel is only allowed on UpdateOne operations")
+	}
+	if m.id == nil || m.oldValue == nil {
+		return v, errors.New("OldUpstreamModel requires an ID field in the mutation")
+	}
+	oldValue, err := m.oldValue(ctx)
+	if err != nil {
+		return v, fmt.Errorf("querying old value for OldUpstreamModel: %w", err)
+	}
+	return oldValue.UpstreamModel, nil
+}
+
+// ClearUpstreamModel clears the value of the "upstream_model" field.
+func (m *UsageLogMutation) ClearUpstreamModel() {
+	m.upstream_model = nil
+	m.clearedFields[usagelog.FieldUpstreamModel] = struct{}{}
+}
+
+// UpstreamModelCleared returns if the "upstream_model" field was cleared in this mutation.
+func (m *UsageLogMutation) UpstreamModelCleared() bool {
+	_, ok := m.clearedFields[usagelog.FieldUpstreamModel]
+	return ok
+}
+
+// ResetUpstreamModel resets all changes to the "upstream_model" field.
+func (m *UsageLogMutation) ResetUpstreamModel() {
+	m.upstream_model = nil
+	delete(m.clearedFields, usagelog.FieldUpstreamModel)
+}
+
 // SetGroupID sets the "group_id" field.
 func (m *UsageLogMutation) SetGroupID(i int64) {
 	m.group = &i
@@ -20197,7 +20247,7 @@ func (m *UsageLogMutation) Type() string {
 // order to get all numeric fields that were incremented/decremented, call
 // AddedFields().
 func (m *UsageLogMutation) Fields() []string {
-	fields := make([]string, 0, 32)
+	fields := make([]string, 0, 33)
 	if m.user != nil {
 		fields = append(fields, usagelog.FieldUserID)
 	}
@@ -20213,6 +20263,9 @@ func (m *UsageLogMutation) Fields() []string {
 	if m.model != nil {
 		fields = append(fields, usagelog.FieldModel)
 	}
+	if m.upstream_model != nil {
+		fields = append(fields, usagelog.FieldUpstreamModel)
+	}
 	if m.group != nil {
 		fields = append(fields, usagelog.FieldGroupID)
 	}
@@ -20312,6 +20365,8 @@ func (m *UsageLogMutation) Field(name string) (ent.Value, bool) {
 		return m.RequestID()
 	case usagelog.FieldModel:
 		return m.Model()
+	case usagelog.FieldUpstreamModel:
+		return m.UpstreamModel()
 	case usagelog.FieldGroupID:
 		return m.GroupID()
 	case usagelog.FieldSubscriptionID:
@@ -20385,6 +20440,8 @@ func (m *UsageLogMutation) OldField(ctx context.Context, name string) (ent.Value
 		return m.OldRequestID(ctx)
 	case usagelog.FieldModel:
 		return m.OldModel(ctx)
+	case usagelog.FieldUpstreamModel:
+		return m.OldUpstreamModel(ctx)
 	case usagelog.FieldGroupID:
 		return m.OldGroupID(ctx)
 	case usagelog.FieldSubscriptionID:
@@ -20483,6 +20540,13 @@ func (m *UsageLogMutation) SetField(name string, value ent.Value) error {
 		}
 		m.SetModel(v)
 		return nil
+	case usagelog.FieldUpstreamModel:
+		v, ok := value.(string)
+		if !ok {
+			return fmt.Errorf("unexpected type %T for field %s", value, name)
+		}
+		m.SetUpstreamModel(v)
+		return nil
 	case usagelog.FieldGroupID:
 		v, ok := value.(int64)
 		if !ok {
@@ -20921,6 +20985,9 @@ func (m *UsageLogMutation) AddField(name string, value ent.Value) error {
 // mutation.
 func (m *UsageLogMutation) ClearedFields() []string {
 	var fields []string
+	if m.FieldCleared(usagelog.FieldUpstreamModel) {
+		fields = append(fields, usagelog.FieldUpstreamModel)
+	}
 	if m.FieldCleared(usagelog.FieldGroupID) {
 		fields = append(fields, usagelog.FieldGroupID)
 	}
@@ -20962,6 +21029,9 @@ func (m *UsageLogMutation) FieldCleared(name string) bool {
 // error if the field is not defined in the schema.
 func (m *UsageLogMutation) ClearField(name string) error {
 	switch name {
+	case usagelog.FieldUpstreamModel:
+		m.ClearUpstreamModel()
+		return nil
 	case usagelog.FieldGroupID:
 		m.ClearGroupID()
 		return nil
@@ -21012,6 +21082,9 @@ func (m *UsageLogMutation) ResetField(name string) error {
 	case usagelog.FieldModel:
 		m.ResetModel()
 		return nil
+	case usagelog.FieldUpstreamModel:
+		m.ResetUpstreamModel()
+		return nil
 	case usagelog.FieldGroupID:
 		m.ResetGroupID()
 		return nil

backend/ent/runtime/runtime.go

@@ -821,92 +821,96 @@ func init() {
 			return nil
 		}
 	}()
+	// usagelogDescUpstreamModel is the schema descriptor for upstream_model field.
+	usagelogDescUpstreamModel := usagelogFields[5].Descriptor()
+	// usagelog.UpstreamModelValidator is a validator for the "upstream_model" field. It is called by the builders before save.
+	usagelog.UpstreamModelValidator = usagelogDescUpstreamModel.Validators[0].(func(string) error)
 	// usagelogDescInputTokens is the schema descriptor for input_tokens field.
-	usagelogDescInputTokens := usagelogFields[7].Descriptor()
+	usagelogDescInputTokens := usagelogFields[8].Descriptor()
 	// usagelog.DefaultInputTokens holds the default value on creation for the input_tokens field.
 	usagelog.DefaultInputTokens = usagelogDescInputTokens.Default.(int)
 	// usagelogDescOutputTokens is the schema descriptor for output_tokens field.
-	usagelogDescOutputTokens := usagelogFields[8].Descriptor()
+	usagelogDescOutputTokens := usagelogFields[9].Descriptor()
 	// usagelog.DefaultOutputTokens holds the default value on creation for the output_tokens field.
 	usagelog.DefaultOutputTokens = usagelogDescOutputTokens.Default.(int)
 	// usagelogDescCacheCreationTokens is the schema descriptor for cache_creation_tokens field.
-	usagelogDescCacheCreationTokens := usagelogFields[9].Descriptor()
+	usagelogDescCacheCreationTokens := usagelogFields[10].Descriptor()
 	// usagelog.DefaultCacheCreationTokens holds the default value on creation for the cache_creation_tokens field.
 	usagelog.DefaultCacheCreationTokens = usagelogDescCacheCreationTokens.Default.(int)
 	// usagelogDescCacheReadTokens is the schema descriptor for cache_read_tokens field.
-	usagelogDescCacheReadTokens := usagelogFields[10].Descriptor()
+	usagelogDescCacheReadTokens := usagelogFields[11].Descriptor()
 	// usagelog.DefaultCacheReadTokens holds the default value on creation for the cache_read_tokens field.
 	usagelog.DefaultCacheReadTokens = usagelogDescCacheReadTokens.Default.(int)
 	// usagelogDescCacheCreation5mTokens is the schema descriptor for cache_creation_5m_tokens field.
-	usagelogDescCacheCreation5mTokens := usagelogFields[11].Descriptor()
+	usagelogDescCacheCreation5mTokens := usagelogFields[12].Descriptor()
 	// usagelog.DefaultCacheCreation5mTokens holds the default value on creation for the cache_creation_5m_tokens field.
 	usagelog.DefaultCacheCreation5mTokens = usagelogDescCacheCreation5mTokens.Default.(int)
 	// usagelogDescCacheCreation1hTokens is the schema descriptor for cache_creation_1h_tokens field.
-	usagelogDescCacheCreation1hTokens := usagelogFields[12].Descriptor()
+	usagelogDescCacheCreation1hTokens := usagelogFields[13].Descriptor()
 	// usagelog.DefaultCacheCreation1hTokens holds the default value on creation for the cache_creation_1h_tokens field.
 	usagelog.DefaultCacheCreation1hTokens = usagelogDescCacheCreation1hTokens.Default.(int)
 	// usagelogDescInputCost is the schema descriptor for input_cost field.
-	usagelogDescInputCost := usagelogFields[13].Descriptor()
+	usagelogDescInputCost := usagelogFields[14].Descriptor()
 	// usagelog.DefaultInputCost holds the default value on creation for the input_cost field.
 	usagelog.DefaultInputCost = usagelogDescInputCost.Default.(float64)
 	// usagelogDescOutputCost is the schema descriptor for output_cost field.
-	usagelogDescOutputCost := usagelogFields[14].Descriptor()
+	usagelogDescOutputCost := usagelogFields[15].Descriptor()
 	// usagelog.DefaultOutputCost holds the default value on creation for the output_cost field.
 	usagelog.DefaultOutputCost = usagelogDescOutputCost.Default.(float64)
 	// usagelogDescCacheCreationCost is the schema descriptor for cache_creation_cost field.
-	usagelogDescCacheCreationCost := usagelogFields[15].Descriptor()
+	usagelogDescCacheCreationCost := usagelogFields[16].Descriptor()
 	// usagelog.DefaultCacheCreationCost holds the default value on creation for the cache_creation_cost field.
 	usagelog.DefaultCacheCreationCost = usagelogDescCacheCreationCost.Default.(float64)
 	// usagelogDescCacheReadCost is the schema descriptor for cache_read_cost field.
-	usagelogDescCacheReadCost := usagelogFields[16].Descriptor()
+	usagelogDescCacheReadCost := usagelogFields[17].Descriptor()
 	// usagelog.DefaultCacheReadCost holds the default value on creation for the cache_read_cost field.
 	usagelog.DefaultCacheReadCost = usagelogDescCacheReadCost.Default.(float64)
 	// usagelogDescTotalCost is the schema descriptor for total_cost field.
-	usagelogDescTotalCost := usagelogFields[17].Descriptor()
+	usagelogDescTotalCost := usagelogFields[18].Descriptor()
 	// usagelog.DefaultTotalCost holds the default value on creation for the total_cost field.
 	usagelog.DefaultTotalCost = usagelogDescTotalCost.Default.(float64)
 	// usagelogDescActualCost is the schema descriptor for actual_cost field.
-	usagelogDescActualCost := usagelogFields[18].Descriptor()
+	usagelogDescActualCost := usagelogFields[19].Descriptor()
 	// usagelog.DefaultActualCost holds the default value on creation for the actual_cost field.
 	usagelog.DefaultActualCost = usagelogDescActualCost.Default.(float64)
 	// usagelogDescRateMultiplier is the schema descriptor for rate_multiplier field.
-	usagelogDescRateMultiplier := usagelogFields[19].Descriptor()
+	usagelogDescRateMultiplier := usagelogFields[20].Descriptor()
 	// usagelog.DefaultRateMultiplier holds the default value on creation for the rate_multiplier field.
 	usagelog.DefaultRateMultiplier = usagelogDescRateMultiplier.Default.(float64)
 	// usagelogDescBillingType is the schema descriptor for billing_type field.
-	usagelogDescBillingType := usagelogFields[21].Descriptor()
+	usagelogDescBillingType := usagelogFields[22].Descriptor()
 	// usagelog.DefaultBillingType holds the default value on creation for the billing_type field.
 	usagelog.DefaultBillingType = usagelogDescBillingType.Default.(int8)
 	// usagelogDescStream is the schema descriptor for stream field.
-	usagelogDescStream := usagelogFields[22].Descriptor()
+	usagelogDescStream := usagelogFields[23].Descriptor()
 	// usagelog.DefaultStream holds the default value on creation for the stream field.
 	usagelog.DefaultStream = usagelogDescStream.Default.(bool)
 	// usagelogDescUserAgent is the schema descriptor for user_agent field.
-	usagelogDescUserAgent := usagelogFields[25].Descriptor()
+	usagelogDescUserAgent := usagelogFields[26].Descriptor()
 	// usagelog.UserAgentValidator is a validator for the "user_agent" field. It is called by the builders before save.
 	usagelog.UserAgentValidator = usagelogDescUserAgent.Validators[0].(func(string) error)
 	// usagelogDescIPAddress is the schema descriptor for ip_address field.
-	usagelogDescIPAddress := usagelogFields[26].Descriptor()
+	usagelogDescIPAddress := usagelogFields[27].Descriptor()
 	// usagelog.IPAddressValidator is a validator for the "ip_address" field. It is called by the builders before save.
 	usagelog.IPAddressValidator = usagelogDescIPAddress.Validators[0].(func(string) error)
 	// usagelogDescImageCount is the schema descriptor for image_count field.
-	usagelogDescImageCount := usagelogFields[27].Descriptor()
+	usagelogDescImageCount := usagelogFields[28].Descriptor()
 	// usagelog.DefaultImageCount holds the default value on creation for the image_count field.
 	usagelog.DefaultImageCount = usagelogDescImageCount.Default.(int)
 	// usagelogDescImageSize is the schema descriptor for image_size field.
-	usagelogDescImageSize := usagelogFields[28].Descriptor()
+	usagelogDescImageSize := usagelogFields[29].Descriptor()
 	// usagelog.ImageSizeValidator is a validator for the "image_size" field. It is called by the builders before save.
 	usagelog.ImageSizeValidator = usagelogDescImageSize.Validators[0].(func(string) error)
 	// usagelogDescMediaType is the schema descriptor for media_type field.
-	usagelogDescMediaType := usagelogFields[29].Descriptor()
+	usagelogDescMediaType := usagelogFields[30].Descriptor()
 	// usagelog.MediaTypeValidator is a validator for the "media_type" field. It is called by the builders before save.
 	usagelog.MediaTypeValidator = usagelogDescMediaType.Validators[0].(func(string) error)
 	// usagelogDescCacheTTLOverridden is the schema descriptor for cache_ttl_overridden field.
-	usagelogDescCacheTTLOverridden := usagelogFields[30].Descriptor()
+	usagelogDescCacheTTLOverridden := usagelogFields[31].Descriptor()
 	// usagelog.DefaultCacheTTLOverridden holds the default value on creation for the cache_ttl_overridden field.
 	usagelog.DefaultCacheTTLOverridden = usagelogDescCacheTTLOverridden.Default.(bool)
 	// usagelogDescCreatedAt is the schema descriptor for created_at field.
-	usagelogDescCreatedAt := usagelogFields[31].Descriptor()
+	usagelogDescCreatedAt := usagelogFields[32].Descriptor()
 	// usagelog.DefaultCreatedAt holds the default value on creation for the created_at field.
 	usagelog.DefaultCreatedAt = usagelogDescCreatedAt.Default.(func() time.Time)
 	userMixin := schema.User{}.Mixin()

backend/ent/schema/usage_log.go

@@ -41,6 +41,12 @@ func (UsageLog) Fields() []ent.Field {
 		field.String("model").
 			MaxLen(100).
 			NotEmpty(),
+		// UpstreamModel stores the actual upstream model name when model mapping
+		// is applied. NULL means no mapping — the requested model was used as-is.
+		field.String("upstream_model").
+			MaxLen(100).
+			Optional().
+			Nillable(),
 		field.Int64("group_id").
 			Optional().
 			Nillable(),

backend/ent/usagelog.go

@@ -32,6 +32,8 @@ type UsageLog struct {
 	RequestID string `json:"request_id,omitempty"`
 	// Model holds the value of the "model" field.
 	Model string `json:"model,omitempty"`
+	// UpstreamModel holds the value of the "upstream_model" field.
+	UpstreamModel *string `json:"upstream_model,omitempty"`
 	// GroupID holds the value of the "group_id" field.
 	GroupID *int64 `json:"group_id,omitempty"`
 	// SubscriptionID holds the value of the "subscription_id" field.
@@ -175,7 +177,7 @@ func (*UsageLog) scanValues(columns []string) ([]any, error) {
 			values[i] = new(sql.NullFloat64)
 		case usagelog.FieldID, usagelog.FieldUserID, usagelog.FieldAPIKeyID, usagelog.FieldAccountID, usagelog.FieldGroupID, usagelog.FieldSubscriptionID, usagelog.FieldInputTokens, usagelog.FieldOutputTokens, usagelog.FieldCacheCreationTokens, usagelog.FieldCacheReadTokens, usagelog.FieldCacheCreation5mTokens, usagelog.FieldCacheCreation1hTokens, usagelog.FieldBillingType, usagelog.FieldDurationMs, usagelog.FieldFirstTokenMs, usagelog.FieldImageCount:
 			values[i] = new(sql.NullInt64)
-		case usagelog.FieldRequestID, usagelog.FieldModel, usagelog.FieldUserAgent, usagelog.FieldIPAddress, usagelog.FieldImageSize, usagelog.FieldMediaType:
+		case usagelog.FieldRequestID, usagelog.FieldModel, usagelog.FieldUpstreamModel, usagelog.FieldUserAgent, usagelog.FieldIPAddress, usagelog.FieldImageSize, usagelog.FieldMediaType:
 			values[i] = new(sql.NullString)
 		case usagelog.FieldCreatedAt:
 			values[i] = new(sql.NullTime)
@@ -230,6 +232,13 @@ func (_m *UsageLog) assignValues(columns []string, values []any) error {
 			} else if value.Valid {
 				_m.Model = value.String
 			}
+		case usagelog.FieldUpstreamModel:
+			if value, ok := values[i].(*sql.NullString); !ok {
+				return fmt.Errorf("unexpected type %T for field upstream_model", values[i])
+			} else if value.Valid {
+				_m.UpstreamModel = new(string)
+				*_m.UpstreamModel = value.String
+			}
 		case usagelog.FieldGroupID:
 			if value, ok := values[i].(*sql.NullInt64); !ok {
 				return fmt.Errorf("unexpected type %T for field group_id", values[i])
@@ -477,6 +486,11 @@ func (_m *UsageLog) String() string {
 	builder.WriteString("model=")
 	builder.WriteString(_m.Model)
 	builder.WriteString(", ")
+	if v := _m.UpstreamModel; v != nil {
+		builder.WriteString("upstream_model=")
+		builder.WriteString(*v)
+	}
+	builder.WriteString(", ")
 	if v := _m.GroupID; v != nil {
 		builder.WriteString("group_id=")
 		builder.WriteString(fmt.Sprintf("%v", *v))

backend/ent/usagelog/usagelog.go

@@ -24,6 +24,8 @@ const (
 	FieldRequestID = "request_id"
 	// FieldModel holds the string denoting the model field in the database.
 	FieldModel = "model"
+	// FieldUpstreamModel holds the string denoting the upstream_model field in the database.
+	FieldUpstreamModel = "upstream_model"
 	// FieldGroupID holds the string denoting the group_id field in the database.
 	FieldGroupID = "group_id"
 	// FieldSubscriptionID holds the string denoting the subscription_id field in the database.
@@ -135,6 +137,7 @@ var Columns = []string{
 	FieldAccountID,
 	FieldRequestID,
 	FieldModel,
+	FieldUpstreamModel,
 	FieldGroupID,
 	FieldSubscriptionID,
 	FieldInputTokens,
@@ -179,6 +182,8 @@ var (
 	RequestIDValidator func(string) error
 	// ModelValidator is a validator for the "model" field. It is called by the builders before save.
 	ModelValidator func(string) error
+	// UpstreamModelValidator is a validator for the "upstream_model" field. It is called by the builders before save.
+	UpstreamModelValidator func(string) error
 	// DefaultInputTokens holds the default value on creation for the "input_tokens" field.
 	DefaultInputTokens int
 	// DefaultOutputTokens holds the default value on creation for the "output_tokens" field.
@@ -258,6 +263,11 @@ func ByModel(opts ...sql.OrderTermOption) OrderOption {
 	return sql.OrderByField(FieldModel, opts...).ToFunc()
 }
 
+// ByUpstreamModel orders the results by the upstream_model field.
+func ByUpstreamModel(opts ...sql.OrderTermOption) OrderOption {
+	return sql.OrderByField(FieldUpstreamModel, opts...).ToFunc()
+}
+
 // ByGroupID orders the results by the group_id field.
 func ByGroupID(opts ...sql.OrderTermOption) OrderOption {
 	return sql.OrderByField(FieldGroupID, opts...).ToFunc()

backend/ent/usagelog/where.go

@@ -80,6 +80,11 @@ func Model(v string) predicate.UsageLog {
 	return predicate.UsageLog(sql.FieldEQ(FieldModel, v))
 }
 
+// UpstreamModel applies equality check predicate on the "upstream_model" field. It's identical to UpstreamModelEQ.
+func UpstreamModel(v string) predicate.UsageLog {
+	return predicate.UsageLog(sql.FieldEQ(FieldUpstreamModel, v))
+}
+
 // GroupID applies equality check predicate on the "group_id" field. It's identical to GroupIDEQ.
 func GroupID(v int64) predicate.UsageLog {
 	return predicate.UsageLog(sql.FieldEQ(FieldGroupID, v))
@@ -405,6 +410,81 @@ func ModelContainsFold(v string) predicate.UsageLog {
 	return predicate.UsageLog(sql.FieldContainsFold(FieldModel, v))
 }
 
+// UpstreamModelEQ applies the EQ predicate on the "upstream_model" field.
+func UpstreamModelEQ(v string) predicate.UsageLog {
+	return predicate.UsageLog(sql.FieldEQ(FieldUpstreamModel, v))
+}
+
+// UpstreamModelNEQ applies the NEQ predicate on the "upstream_model" field.
+func UpstreamModelNEQ(v string) predicate.UsageLog {
+	return predicate.UsageLog(sql.FieldNEQ(FieldUpstreamModel, v))
+}
+
+// UpstreamModelIn applies the In predicate on the "upstream_model" field.
+func UpstreamModelIn(vs ...string) predicate.UsageLog {
+	return predicate.UsageLog(sql.FieldIn(FieldUpstreamModel, vs...))
+}
+
+// UpstreamModelNotIn applies the NotIn predicate on the "upstream_model" field.
+func UpstreamModelNotIn(vs ...string) predicate.UsageLog {
+	return predicate.UsageLog(sql.FieldNotIn(FieldUpstreamModel, vs...))
+}
+
+// UpstreamModelGT applies the GT predicate on the "upstream_model" field.
+func UpstreamModelGT(v string) predicate.UsageLog {
+	return predicate.UsageLog(sql.FieldGT(FieldUpstreamModel, v))
+}
+
+// UpstreamModelGTE applies the GTE predicate on the "upstream_model" field.
+func UpstreamModelGTE(v string) predicate.UsageLog {
+	return predicate.UsageLog(sql.FieldGTE(FieldUpstreamModel, v))
+}
+
+// UpstreamModelLT applies the LT predicate on the "upstream_model" field.
+func UpstreamModelLT(v string) predicate.UsageLog {
+	return predicate.UsageLog(sql.FieldLT(FieldUpstreamModel, v))
+}
+
+// UpstreamModelLTE applies the LTE predicate on the "upstream_model" field.
+func UpstreamModelLTE(v string) predicate.UsageLog {
+	return predicate.UsageLog(sql.FieldLTE(FieldUpstreamModel, v))
+}
+
+// UpstreamModelContains applies the Contains predicate on the "upstream_model" field.
+func UpstreamModelContains(v string) predicate.UsageLog {
+	return predicate.UsageLog(sql.FieldContains(FieldUpstreamModel, v))
+}
+
+// UpstreamModelHasPrefix applies the HasPrefix predicate on the "upstream_model" field.
+func UpstreamModelHasPrefix(v string) predicate.UsageLog {
+	return predicate.UsageLog(sql.FieldHasPrefix(FieldUpstreamModel, v))
+}
+
+// UpstreamModelHasSuffix applies the HasSuffix predicate on the "upstream_model" field.
+func UpstreamModelHasSuffix(v string) predicate.UsageLog {
+	return predicate.UsageLog(sql.FieldHasSuffix(FieldUpstreamModel, v))
+}
+
+// UpstreamModelIsNil applies the IsNil predicate on the "upstream_model" field.
+func UpstreamModelIsNil() predicate.UsageLog {
+	return predicate.UsageLog(sql.FieldIsNull(FieldUpstreamModel))
+}
+
+// UpstreamModelNotNil applies the NotNil predicate on the "upstream_model" field.
+func UpstreamModelNotNil() predicate.UsageLog {
+	return predicate.UsageLog(sql.FieldNotNull(FieldUpstreamModel))
+}
+
+// UpstreamModelEqualFold applies the EqualFold predicate on the "upstream_model" field.
+func UpstreamModelEqualFold(v string) predicate.UsageLog {
+	return predicate.UsageLog(sql.FieldEqualFold(FieldUpstreamModel, v))
+}
+
+// UpstreamModelContainsFold applies the ContainsFold predicate on the "upstream_model" field.
+func UpstreamModelContainsFold(v string) predicate.UsageLog {
+	return predicate.UsageLog(sql.FieldContainsFold(FieldUpstreamModel, v))
+}
+
 // GroupIDEQ applies the EQ predicate on the "group_id" field.
 func GroupIDEQ(v int64) predicate.UsageLog {
 	return predicate.UsageLog(sql.FieldEQ(FieldGroupID, v))

backend/ent/usagelog_create.go

@@ -57,6 +57,20 @@ func (_c *UsageLogCreate) SetModel(v string) *UsageLogCreate {
 	return _c
 }
 
+// SetUpstreamModel sets the "upstream_model" field.
+func (_c *UsageLogCreate) SetUpstreamModel(v string) *UsageLogCreate {
+	_c.mutation.SetUpstreamModel(v)
+	return _c
+}
+
+// SetNillableUpstreamModel sets the "upstream_model" field if the given value is not nil.
+func (_c *UsageLogCreate) SetNillableUpstreamModel(v *string) *UsageLogCreate {
+	if v != nil {
+		_c.SetUpstreamModel(*v)
+	}
+	return _c
+}
+
 // SetGroupID sets the "group_id" field.
 func (_c *UsageLogCreate) SetGroupID(v int64) *UsageLogCreate {
 	_c.mutation.SetGroupID(v)
@@ -596,6 +610,11 @@ func (_c *UsageLogCreate) check() error {
 			return &ValidationError{Name: "model", err: fmt.Errorf(`ent: validator failed for field "UsageLog.model": %w`, err)}
 		}
 	}
+	if v, ok := _c.mutation.UpstreamModel(); ok {
+		if err := usagelog.UpstreamModelValidator(v); err != nil {
+			return &ValidationError{Name: "upstream_model", err: fmt.Errorf(`ent: validator failed for field "UsageLog.upstream_model": %w`, err)}
+		}
+	}
 	if _, ok := _c.mutation.InputTokens(); !ok {
 		return &ValidationError{Name: "input_tokens", err: errors.New(`ent: missing required field "UsageLog.input_tokens"`)}
 	}
@@ -714,6 +733,10 @@ func (_c *UsageLogCreate) createSpec() (*UsageLog, *sqlgraph.CreateSpec) {
 		_spec.SetField(usagelog.FieldModel, field.TypeString, value)
 		_node.Model = value
 	}
+	if value, ok := _c.mutation.UpstreamModel(); ok {
+		_spec.SetField(usagelog.FieldUpstreamModel, field.TypeString, value)
+		_node.UpstreamModel = &value
+	}
 	if value, ok := _c.mutation.InputTokens(); ok {
 		_spec.SetField(usagelog.FieldInputTokens, field.TypeInt, value)
 		_node.InputTokens = value
@@ -1011,6 +1034,24 @@ func (u *UsageLogUpsert) UpdateModel() *UsageLogUpsert {
 	return u
 }
 
+// SetUpstreamModel sets the "upstream_model" field.
+func (u *UsageLogUpsert) SetUpstreamModel(v string) *UsageLogUpsert {
+	u.Set(usagelog.FieldUpstreamModel, v)
+	return u
+}
+
+// UpdateUpstreamModel sets the "upstream_model" field to the value that was provided on create.
+func (u *UsageLogUpsert) UpdateUpstreamModel() *UsageLogUpsert {
+	u.SetExcluded(usagelog.FieldUpstreamModel)
+	return u
+}
+
+// ClearUpstreamModel clears the value of the "upstream_model" field.
+func (u *UsageLogUpsert) ClearUpstreamModel() *UsageLogUpsert {
+	u.SetNull(usagelog.FieldUpstreamModel)
+	return u
+}
+
 // SetGroupID sets the "group_id" field.
 func (u *UsageLogUpsert) SetGroupID(v int64) *UsageLogUpsert {
 	u.Set(usagelog.FieldGroupID, v)
@@ -1600,6 +1641,27 @@ func (u *UsageLogUpsertOne) UpdateModel() *UsageLogUpsertOne {
 	})
 }
 
+// SetUpstreamModel sets the "upstream_model" field.
+func (u *UsageLogUpsertOne) SetUpstreamModel(v string) *UsageLogUpsertOne {
+	return u.Update(func(s *UsageLogUpsert) {
+		s.SetUpstreamModel(v)
+	})
+}
+
+// UpdateUpstreamModel sets the "upstream_model" field to the value that was provided on create.
+func (u *UsageLogUpsertOne) UpdateUpstreamModel() *UsageLogUpsertOne {
+	return u.Update(func(s *UsageLogUpsert) {
+		s.UpdateUpstreamModel()
+	})
+}
+
+// ClearUpstreamModel clears the value of the "upstream_model" field.
+func (u *UsageLogUpsertOne) ClearUpstreamModel() *UsageLogUpsertOne {
+	return u.Update(func(s *UsageLogUpsert) {
+		s.ClearUpstreamModel()
+	})
+}
+
 // SetGroupID sets the "group_id" field.
 func (u *UsageLogUpsertOne) SetGroupID(v int64) *UsageLogUpsertOne {
 	return u.Update(func(s *UsageLogUpsert) {
@@ -2434,6 +2496,27 @@ func (u *UsageLogUpsertBulk) UpdateModel() *UsageLogUpsertBulk {
 	})
 }
 
+// SetUpstreamModel sets the "upstream_model" field.
+func (u *UsageLogUpsertBulk) SetUpstreamModel(v string) *UsageLogUpsertBulk {
+	return u.Update(func(s *UsageLogUpsert) {
+		s.SetUpstreamModel(v)
+	})
+}
+
+// UpdateUpstreamModel sets the "upstream_model" field to the value that was provided on create.
+func (u *UsageLogUpsertBulk) UpdateUpstreamModel() *UsageLogUpsertBulk {
+	return u.Update(func(s *UsageLogUpsert) {
+		s.UpdateUpstreamModel()
+	})
+}
+
+// ClearUpstreamModel clears the value of the "upstream_model" field.
+func (u *UsageLogUpsertBulk) ClearUpstreamModel() *UsageLogUpsertBulk {
+	return u.Update(func(s *UsageLogUpsert) {
+		s.ClearUpstreamModel()
+	})
+}
+
 // SetGroupID sets the "group_id" field.
 func (u *UsageLogUpsertBulk) SetGroupID(v int64) *UsageLogUpsertBulk {
 	return u.Update(func(s *UsageLogUpsert) {

backend/ent/usagelog_update.go

@@ -102,6 +102,26 @@ func (_u *UsageLogUpdate) SetNillableModel(v *string) *UsageLogUpdate {
 	return _u
 }
 
+// SetUpstreamModel sets the "upstream_model" field.
+func (_u *UsageLogUpdate) SetUpstreamModel(v string) *UsageLogUpdate {
+	_u.mutation.SetUpstreamModel(v)
+	return _u
+}
+
+// SetNillableUpstreamModel sets the "upstream_model" field if the given value is not nil.
+func (_u *UsageLogUpdate) SetNillableUpstreamModel(v *string) *UsageLogUpdate {
+	if v != nil {
+		_u.SetUpstreamModel(*v)
+	}
+	return _u
+}
+
+// ClearUpstreamModel clears the value of the "upstream_model" field.
+func (_u *UsageLogUpdate) ClearUpstreamModel() *UsageLogUpdate {
+	_u.mutation.ClearUpstreamModel()
+	return _u
+}
+
 // SetGroupID sets the "group_id" field.
 func (_u *UsageLogUpdate) SetGroupID(v int64) *UsageLogUpdate {
 	_u.mutation.SetGroupID(v)
@@ -745,6 +765,11 @@ func (_u *UsageLogUpdate) check() error {
 			return &ValidationError{Name: "model", err: fmt.Errorf(`ent: validator failed for field "UsageLog.model": %w`, err)}
 		}
 	}
+	if v, ok := _u.mutation.UpstreamModel(); ok {
+		if err := usagelog.UpstreamModelValidator(v); err != nil {
+			return &ValidationError{Name: "upstream_model", err: fmt.Errorf(`ent: validator failed for field "UsageLog.upstream_model": %w`, err)}
+		}
+	}
 	if v, ok := _u.mutation.UserAgent(); ok {
 		if err := usagelog.UserAgentValidator(v); err != nil {
 			return &ValidationError{Name: "user_agent", err: fmt.Errorf(`ent: validator failed for field "UsageLog.user_agent": %w`, err)}
@@ -795,6 +820,12 @@ func (_u *UsageLogUpdate) sqlSave(ctx context.Context) (_node int, err error) {
 	if value, ok := _u.mutation.Model(); ok {
 		_spec.SetField(usagelog.FieldModel, field.TypeString, value)
 	}
+	if value, ok := _u.mutation.UpstreamModel(); ok {
+		_spec.SetField(usagelog.FieldUpstreamModel, field.TypeString, value)
+	}
+	if _u.mutation.UpstreamModelCleared() {
+		_spec.ClearField(usagelog.FieldUpstreamModel, field.TypeString)
+	}
 	if value, ok := _u.mutation.InputTokens(); ok {
 		_spec.SetField(usagelog.FieldInputTokens, field.TypeInt, value)
 	}
@@ -1177,6 +1208,26 @@ func (_u *UsageLogUpdateOne) SetNillableModel(v *string) *UsageLogUpdateOne {
 	return _u
 }
 
+// SetUpstreamModel sets the "upstream_model" field.
+func (_u *UsageLogUpdateOne) SetUpstreamModel(v string) *UsageLogUpdateOne {
+	_u.mutation.SetUpstreamModel(v)
+	return _u
+}
+
+// SetNillableUpstreamModel sets the "upstream_model" field if the given value is not nil.
+func (_u *UsageLogUpdateOne) SetNillableUpstreamModel(v *string) *UsageLogUpdateOne {
+	if v != nil {
+		_u.SetUpstreamModel(*v)
+	}
+	return _u
+}
+
+// ClearUpstreamModel clears the value of the "upstream_model" field.
+func (_u *UsageLogUpdateOne) ClearUpstreamModel() *UsageLogUpdateOne {
+	_u.mutation.ClearUpstreamModel()
+	return _u
+}
+
 // SetGroupID sets the "group_id" field.
 func (_u *UsageLogUpdateOne) SetGroupID(v int64) *UsageLogUpdateOne {
 	_u.mutation.SetGroupID(v)
@@ -1833,6 +1884,11 @@ func (_u *UsageLogUpdateOne) check() error {
 			return &ValidationError{Name: "model", err: fmt.Errorf(`ent: validator failed for field "UsageLog.model": %w`, err)}
 		}
 	}
+	if v, ok := _u.mutation.UpstreamModel(); ok {
+		if err := usagelog.UpstreamModelValidator(v); err != nil {
+			return &ValidationError{Name: "upstream_model", err: fmt.Errorf(`ent: validator failed for field "UsageLog.upstream_model": %w`, err)}
+		}
+	}
 	if v, ok := _u.mutation.UserAgent(); ok {
 		if err := usagelog.UserAgentValidator(v); err != nil {
 			return &ValidationError{Name: "user_agent", err: fmt.Errorf(`ent: validator failed for field "UsageLog.user_agent": %w`, err)}
@@ -1900,6 +1956,12 @@ func (_u *UsageLogUpdateOne) sqlSave(ctx context.Context) (_node *UsageLog, err
 	if value, ok := _u.mutation.Model(); ok {
 		_spec.SetField(usagelog.FieldModel, field.TypeString, value)
 	}
+	if value, ok := _u.mutation.UpstreamModel(); ok {
+		_spec.SetField(usagelog.FieldUpstreamModel, field.TypeString, value)
+	}
+	if _u.mutation.UpstreamModelCleared() {
+		_spec.ClearField(usagelog.FieldUpstreamModel, field.TypeString)
+	}
 	if value, ok := _u.mutation.InputTokens(); ok {
 		_spec.SetField(usagelog.FieldInputTokens, field.TypeInt, value)
 	}

backend/go.mod

@@ -7,7 +7,7 @@ require (
 	github.com/DATA-DOG/go-sqlmock v1.5.2
 	github.com/DouDOU-start/go-sora2api v1.1.0
 	github.com/alitto/pond/v2 v2.6.2
-	github.com/aws/aws-sdk-go-v2 v1.41.2
+	github.com/aws/aws-sdk-go-v2 v1.41.3
 	github.com/aws/aws-sdk-go-v2/config v1.32.10
 	github.com/aws/aws-sdk-go-v2/credentials v1.19.10
 	github.com/aws/aws-sdk-go-v2/service/s3 v1.96.2
@@ -66,7 +66,7 @@ require (
 	github.com/aws/aws-sdk-go-v2/service/sso v1.30.11 // indirect
 	github.com/aws/aws-sdk-go-v2/service/ssooidc v1.35.15 // indirect
 	github.com/aws/aws-sdk-go-v2/service/sts v1.41.7 // indirect
-	github.com/aws/smithy-go v1.24.1 // indirect
+	github.com/aws/smithy-go v1.24.2 // indirect
 	github.com/bdandy/go-errors v1.2.2 // indirect
 	github.com/bdandy/go-socks4 v1.2.3 // indirect
 	github.com/bmatcuk/doublestar v1.3.4 // indirect

backend/go.sum

@@ -22,8 +22,8 @@ github.com/andybalholm/brotli v1.2.0 h1:ukwgCxwYrmACq68yiUqwIWnGY0cTPox/M94sVwTo
 github.com/andybalholm/brotli v1.2.0/go.mod h1:rzTDkvFWvIrjDXZHkuS16NPggd91W3kUSvPlQ1pLaKY=
 github.com/apparentlymart/go-textseg/v15 v15.0.0 h1:uYvfpb3DyLSCGWnctWKGj857c6ew1u1fNQOlOtuGxQY=
 github.com/apparentlymart/go-textseg/v15 v15.0.0/go.mod h1:K8XmNZdhEBkdlyDdvbmmsvpAG721bKi0joRfFdHIWJ4=
-github.com/aws/aws-sdk-go-v2 v1.41.2 h1:LuT2rzqNQsauaGkPK/7813XxcZ3o3yePY0Iy891T2ls=
-github.com/aws/aws-sdk-go-v2 v1.41.2/go.mod h1:IvvlAZQXvTXznUPfRVfryiG1fbzE2NGK6m9u39YQ+S4=
+github.com/aws/aws-sdk-go-v2 v1.41.3 h1:4kQ/fa22KjDt13QCy1+bYADvdgcxpfH18f0zP542kZA=
+github.com/aws/aws-sdk-go-v2 v1.41.3/go.mod h1:mwsPRE8ceUUpiTgF7QmQIJ7lgsKUPQOUl3o72QBrE1o=
 github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream v1.7.5 h1:zWFmPmgw4sveAYi1mRqG+E/g0461cJ5M4bJ8/nc6d3Q=
 github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream v1.7.5/go.mod h1:nVUlMLVV8ycXSb7mSkcNu9e3v/1TJq2RTlrPwhYWr5c=
 github.com/aws/aws-sdk-go-v2/config v1.32.10 h1:9DMthfO6XWZYLfzZglAgW5Fyou2nRI5CuV44sTedKBI=
@@ -58,8 +58,8 @@ github.com/aws/aws-sdk-go-v2/service/ssooidc v1.35.15 h1:edCcNp9eGIUDUCrzoCu1jWA
 github.com/aws/aws-sdk-go-v2/service/ssooidc v1.35.15/go.mod h1:lyRQKED9xWfgkYC/wmmYfv7iVIM68Z5OQ88ZdcV1QbU=
 github.com/aws/aws-sdk-go-v2/service/sts v1.41.7 h1:NITQpgo9A5NrDZ57uOWj+abvXSb83BbyggcUBVksN7c=
 github.com/aws/aws-sdk-go-v2/service/sts v1.41.7/go.mod h1:sks5UWBhEuWYDPdwlnRFn1w7xWdH29Jcpe+/PJQefEs=
-github.com/aws/smithy-go v1.24.1 h1:VbyeNfmYkWoxMVpGUAbQumkODcYmfMRfZ8yQiH30SK0=
-github.com/aws/smithy-go v1.24.1/go.mod h1:LEj2LM3rBRQJxPZTB4KuzZkaZYnZPnvgIhb4pu07mx0=
+github.com/aws/smithy-go v1.24.2 h1:FzA3bu/nt/vDvmnkg+R8Xl46gmzEDam6mZ1hzmwXFng=
+github.com/aws/smithy-go v1.24.2/go.mod h1:YE2RhdIuDbA5E5bTdciG9KrW3+TiEONeUWCqxX9i1Fc=
 github.com/bdandy/go-errors v1.2.2 h1:WdFv/oukjTJCLa79UfkGmwX7ZxONAihKu4V0mLIs11Q=
 github.com/bdandy/go-errors v1.2.2/go.mod h1:NkYHl4Fey9oRRdbB1CoC6e84tuqQHiqrOcZpqFEkBxM=
 github.com/bdandy/go-socks4 v1.2.3 h1:Q6Y2heY1GRjCtHbmlKfnwrKVU/k81LS8mRGLRlmDlic=
@@ -94,10 +94,6 @@ github.com/cespare/xxhash/v2 v2.3.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XL
 github.com/chenzhuoyu/base64x v0.0.0-20211019084208-fb5309c8db06/go.mod h1:DH46F32mSOjUmXrMHnKwZdA8wcEefY7UVqBKYGjpdQY=
 github.com/chenzhuoyu/base64x v0.0.0-20221115062448-fe3a3abad311 h1:qSGYFH7+jGhDF8vLC+iwCD4WpbV1EBDSzWkJODFLams=
 github.com/chenzhuoyu/base64x v0.0.0-20221115062448-fe3a3abad311/go.mod h1:b583jCggY9gE99b6G5LEC39OIiVsWj+R97kbl5odCEk=
-github.com/clipperhouse/stringish v0.1.1 h1:+NSqMOr3GR6k1FdRhhnXrLfztGzuG+VuFDfatpWHKCs=
-github.com/clipperhouse/stringish v0.1.1/go.mod h1:v/WhFtE1q0ovMta2+m+UbpZ+2/HEXNWYXQgCt4hdOzA=
-github.com/clipperhouse/uax29/v2 v2.5.0 h1:x7T0T4eTHDONxFJsL94uKNKPHrclyFI0lm7+w94cO8U=
-github.com/clipperhouse/uax29/v2 v2.5.0/go.mod h1:Wn1g7MK6OoeDT0vL+Q0SQLDz/KpfsVRgg6W7ihQeh4g=
 github.com/coder/websocket v1.8.14 h1:9L0p0iKiNOibykf283eHkKUHHrpG7f65OE3BhhO7v9g=
 github.com/coder/websocket v1.8.14/go.mod h1:NX3SzP+inril6yawo5CQXx8+fk145lPDC6pumgx0mVg=
 github.com/containerd/errdefs v1.0.0 h1:tg5yIfIlQIrxYtu9ajqY42W3lpS19XqdxRQeEwYG8PI=
@@ -234,8 +230,6 @@ github.com/mattn/go-colorable v0.1.13/go.mod h1:7S9/ev0klgBDR4GtXTXX8a3vIGJpMovk
 github.com/mattn/go-isatty v0.0.16/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
 github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
 github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
-github.com/mattn/go-runewidth v0.0.19 h1:v++JhqYnZuu5jSKrk9RbgF5v4CGUjqRfBm05byFGLdw=
-github.com/mattn/go-runewidth v0.0.19/go.mod h1:XBkDxAl56ILZc9knddidhrOlY5R/pDhgLpndooCuJAs=
 github.com/mattn/go-sqlite3 v1.14.17 h1:mCRHCLDUBXgpKAqIKsaAaAsrAlbkeomtRFKXh2L6YIM=
 github.com/mattn/go-sqlite3 v1.14.17/go.mod h1:2eHXhiwb8IkHr+BDWZGa96P6+rkvnG63S2DGjv9HUNg=
 github.com/mdelapenya/tlscert v0.2.0 h1:7H81W6Z/4weDvZBNOfQte5GpIMo0lGYEeWbkGp5LJHI=
@@ -269,8 +263,6 @@ github.com/morikuni/aec v1.0.0 h1:nP9CBfwrvYnBRgY6qfDQkygYDmYwOilePFkwzv4dU8A=
 github.com/morikuni/aec v1.0.0/go.mod h1:BbKIizmSmc5MMPqRYbxO4ZU0S0+P200+tUnFx7PXmsc=
 github.com/ncruces/go-strftime v1.0.0 h1:HMFp8mLCTPp341M/ZnA4qaf7ZlsbTc+miZjCLOFAw7w=
 github.com/ncruces/go-strftime v1.0.0/go.mod h1:Fwc5htZGVVkseilnfgOVb9mKy6w1naJmn9CehxcKcls=
-github.com/olekukonko/tablewriter v0.0.5 h1:P2Ga83D34wi1o9J6Wh1mRuqd4mF/x/lgBS7N7AbDhec=
-github.com/olekukonko/tablewriter v0.0.5/go.mod h1:hPp6KlRPjbx+hW8ykQs1w3UBbZlj6HuIJcUGPhkA7kY=
 github.com/opencontainers/go-digest v1.0.0 h1:apOUWs51W5PlhuyGyz9FCeeBIOUDA/6nW8Oi/yOhh5U=
 github.com/opencontainers/go-digest v1.0.0/go.mod h1:0JzlMkj0TRzQZfJkVvzbP0HBR3IKzErnv2BNG4W4MAM=
 github.com/opencontainers/image-spec v1.1.1 h1:y0fUlFfIZhPF1W537XOLg0/fcx6zcHCJwooC2xJA040=
@@ -322,8 +314,6 @@ github.com/spf13/afero v1.11.0 h1:WJQKhtpdm3v2IzqG8VMqrr6Rf3UYpEF239Jy9wNepM8=
 github.com/spf13/afero v1.11.0/go.mod h1:GH9Y3pIexgf1MTIWtNGyogA5MwRIDXGUr+hbWNoBjkY=
 github.com/spf13/cast v1.6.0 h1:GEiTHELF+vaR5dhz3VqZfFSzZjYbgeKDpBxQVS4GYJ0=
 github.com/spf13/cast v1.6.0/go.mod h1:ancEpBxwJDODSW/UG4rDrAqiKolqNNh2DX3mk86cAdo=
-github.com/spf13/cobra v1.7.0 h1:hyqWnYt1ZQShIddO5kBpj3vu05/++x6tJ6dg8EC572I=
-github.com/spf13/cobra v1.7.0/go.mod h1:uLxZILRyS/50WlhOIKD7W6V5bgeIt+4sICxh6uRMrb0=
 github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
 github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
 github.com/spf13/viper v1.18.2 h1:LUXCnvUvSM6FXAsj6nnfc8Q2tp1dIgUfY9Kc8GsSOiQ=

backend/internal/config/config.go

@@ -934,9 +934,10 @@ type DashboardAggregationConfig struct {
 
 // DashboardAggregationRetentionConfig 预聚合保留窗口
 type DashboardAggregationRetentionConfig struct {
-	UsageLogsDays int `mapstructure:"usage_logs_days"`
-	HourlyDays    int `mapstructure:"hourly_days"`
-	DailyDays     int `mapstructure:"daily_days"`
+	UsageLogsDays         int `mapstructure:"usage_logs_days"`
+	UsageBillingDedupDays int `mapstructure:"usage_billing_dedup_days"`
+	HourlyDays            int `mapstructure:"hourly_days"`
+	DailyDays             int `mapstructure:"daily_days"`
 }
 
 // UsageCleanupConfig 使用记录清理任务配置
@@ -1301,6 +1302,7 @@ func setDefaults() {
 	viper.SetDefault("dashboard_aggregation.backfill_enabled", false)
 	viper.SetDefault("dashboard_aggregation.backfill_max_days", 31)
 	viper.SetDefault("dashboard_aggregation.retention.usage_logs_days", 90)
+	viper.SetDefault("dashboard_aggregation.retention.usage_billing_dedup_days", 365)
 	viper.SetDefault("dashboard_aggregation.retention.hourly_days", 180)
 	viper.SetDefault("dashboard_aggregation.retention.daily_days", 730)
 	viper.SetDefault("dashboard_aggregation.recompute_days", 2)
@@ -1758,6 +1760,12 @@ func (c *Config) Validate() error {
 		if c.DashboardAgg.Retention.UsageLogsDays <= 0 {
 			return fmt.Errorf("dashboard_aggregation.retention.usage_logs_days must be positive")
 		}
+		if c.DashboardAgg.Retention.UsageBillingDedupDays <= 0 {
+			return fmt.Errorf("dashboard_aggregation.retention.usage_billing_dedup_days must be positive")
+		}
+		if c.DashboardAgg.Retention.UsageBillingDedupDays < c.DashboardAgg.Retention.UsageLogsDays {
+			return fmt.Errorf("dashboard_aggregation.retention.usage_billing_dedup_days must be greater than or equal to usage_logs_days")
+		}
 		if c.DashboardAgg.Retention.HourlyDays <= 0 {
 			return fmt.Errorf("dashboard_aggregation.retention.hourly_days must be positive")
 		}
@@ -1780,6 +1788,14 @@ func (c *Config) Validate() error {
 		if c.DashboardAgg.Retention.UsageLogsDays < 0 {
 			return fmt.Errorf("dashboard_aggregation.retention.usage_logs_days must be non-negative")
 		}
+		if c.DashboardAgg.Retention.UsageBillingDedupDays < 0 {
+			return fmt.Errorf("dashboard_aggregation.retention.usage_billing_dedup_days must be non-negative")
+		}
+		if c.DashboardAgg.Retention.UsageBillingDedupDays > 0 &&
+			c.DashboardAgg.Retention.UsageLogsDays > 0 &&
+			c.DashboardAgg.Retention.UsageBillingDedupDays < c.DashboardAgg.Retention.UsageLogsDays {
+			return fmt.Errorf("dashboard_aggregation.retention.usage_billing_dedup_days must be greater than or equal to usage_logs_days")
+		}
 		if c.DashboardAgg.Retention.HourlyDays < 0 {
 			return fmt.Errorf("dashboard_aggregation.retention.hourly_days must be non-negative")
 		}

backend/internal/config/config_test.go

@@ -441,6 +441,9 @@ func TestLoadDefaultDashboardAggregationConfig(t *testing.T) {
 	if cfg.DashboardAgg.Retention.UsageLogsDays != 90 {
 		t.Fatalf("DashboardAgg.Retention.UsageLogsDays = %d, want 90", cfg.DashboardAgg.Retention.UsageLogsDays)
 	}
+	if cfg.DashboardAgg.Retention.UsageBillingDedupDays != 365 {
+		t.Fatalf("DashboardAgg.Retention.UsageBillingDedupDays = %d, want 365", cfg.DashboardAgg.Retention.UsageBillingDedupDays)
+	}
 	if cfg.DashboardAgg.Retention.HourlyDays != 180 {
 		t.Fatalf("DashboardAgg.Retention.HourlyDays = %d, want 180", cfg.DashboardAgg.Retention.HourlyDays)
 	}
@@ -1016,6 +1019,23 @@ func TestValidateConfigErrors(t *testing.T) {
 			mutate:  func(c *Config) { c.DashboardAgg.Enabled = true; c.DashboardAgg.Retention.UsageLogsDays = 0 },
 			wantErr: "dashboard_aggregation.retention.usage_logs_days",
 		},
+		{
+			name: "dashboard aggregation dedup retention",
+			mutate: func(c *Config) {
+				c.DashboardAgg.Enabled = true
+				c.DashboardAgg.Retention.UsageBillingDedupDays = 0
+			},
+			wantErr: "dashboard_aggregation.retention.usage_billing_dedup_days",
+		},
+		{
+			name: "dashboard aggregation dedup retention smaller than usage logs",
+			mutate: func(c *Config) {
+				c.DashboardAgg.Enabled = true
+				c.DashboardAgg.Retention.UsageLogsDays = 30
+				c.DashboardAgg.Retention.UsageBillingDedupDays = 29
+			},
+			wantErr: "dashboard_aggregation.retention.usage_billing_dedup_days",
+		},
 		{
 			name:    "dashboard aggregation disabled interval",
 			mutate:  func(c *Config) { c.DashboardAgg.Enabled = false; c.DashboardAgg.IntervalSeconds = -1 },

backend/internal/domain/constants.go

@@ -31,6 +31,7 @@ const (
 	AccountTypeSetupToken = "setup-token" // Setup Token类型账号（inference only scope）
 	AccountTypeAPIKey     = "apikey"      // API Key类型账号
 	AccountTypeUpstream   = "upstream"    // 上游透传类型账号（通过 Base URL + API Key 连接上游）
+	AccountTypeBedrock    = "bedrock"     // AWS Bedrock 类型账号（通过 SigV4 签名或 API Key 连接 Bedrock，由 credentials.auth_mode 区分）
 )
 
 // Redeem type constants
@@ -81,13 +82,15 @@ var DefaultAntigravityModelMapping = map[string]string{
 	"claude-opus-4-5-20251101":   "claude-opus-4-6-thinking", // 迁移旧模型
 	"claude-sonnet-4-5-20250929": "claude-sonnet-4-5",
 	// Claude Haiku → Sonnet（无 Haiku 支持）
-	"claude-haiku-4-5":          "claude-sonnet-4-5",
-	"claude-haiku-4-5-20251001": "claude-sonnet-4-5",
+	"claude-haiku-4-5":          "claude-sonnet-4-6",
+	"claude-haiku-4-5-20251001": "claude-sonnet-4-6",
 	// Gemini 2.5 白名单
-	"gemini-2.5-flash":          "gemini-2.5-flash",
-	"gemini-2.5-flash-lite":     "gemini-2.5-flash-lite",
-	"gemini-2.5-flash-thinking": "gemini-2.5-flash-thinking",
-	"gemini-2.5-pro":            "gemini-2.5-pro",
+	"gemini-2.5-flash":               "gemini-2.5-flash",
+	"gemini-2.5-flash-image":         "gemini-2.5-flash-image",
+	"gemini-2.5-flash-image-preview": "gemini-2.5-flash-image",
+	"gemini-2.5-flash-lite":          "gemini-2.5-flash-lite",
+	"gemini-2.5-flash-thinking":      "gemini-2.5-flash-thinking",
+	"gemini-2.5-pro":                 "gemini-2.5-pro",
 	// Gemini 3 白名单
 	"gemini-3-flash":    "gemini-3-flash",
 	"gemini-3-pro-high": "gemini-3-pro-high",
@@ -111,3 +114,27 @@ var DefaultAntigravityModelMapping = map[string]string{
 	"gpt-oss-120b-medium":    "gpt-oss-120b-medium",
 	"tab_flash_lite_preview": "tab_flash_lite_preview",
 }
+
+// DefaultBedrockModelMapping 是 AWS Bedrock 平台的默认模型映射
+// 将 Anthropic 标准模型名映射到 Bedrock 模型 ID
+// 注意：此处的 "us." 前缀仅为默认值，ResolveBedrockModelID 会根据账号配置的
+// aws_region 自动调整为匹配的区域前缀（如 eu.、apac.、jp. 等）
+var DefaultBedrockModelMapping = map[string]string{
+	// Claude Opus
+	"claude-opus-4-6-thinking": "us.anthropic.claude-opus-4-6-v1",
+	"claude-opus-4-6":          "us.anthropic.claude-opus-4-6-v1",
+	"claude-opus-4-5-thinking": "us.anthropic.claude-opus-4-5-20251101-v1:0",
+	"claude-opus-4-5-20251101": "us.anthropic.claude-opus-4-5-20251101-v1:0",
+	"claude-opus-4-1":          "us.anthropic.claude-opus-4-1-20250805-v1:0",
+	"claude-opus-4-20250514":   "us.anthropic.claude-opus-4-20250514-v1:0",
+	// Claude Sonnet
+	"claude-sonnet-4-6-thinking": "us.anthropic.claude-sonnet-4-6",
+	"claude-sonnet-4-6":          "us.anthropic.claude-sonnet-4-6",
+	"claude-sonnet-4-5":          "us.anthropic.claude-sonnet-4-5-20250929-v1:0",
+	"claude-sonnet-4-5-thinking": "us.anthropic.claude-sonnet-4-5-20250929-v1:0",
+	"claude-sonnet-4-5-20250929": "us.anthropic.claude-sonnet-4-5-20250929-v1:0",
+	"claude-sonnet-4-20250514":   "us.anthropic.claude-sonnet-4-20250514-v1:0",
+	// Claude Haiku
+	"claude-haiku-4-5":          "us.anthropic.claude-haiku-4-5-20251001-v1:0",
+	"claude-haiku-4-5-20251001": "us.anthropic.claude-haiku-4-5-20251001-v1:0",
+}

backend/internal/domain/constants_test.go

@@ -6,6 +6,8 @@ func TestDefaultAntigravityModelMapping_ImageCompatibilityAliases(t *testing.T)
 	t.Parallel()
 
 	cases := map[string]string{
+		"gemini-2.5-flash-image":         "gemini-2.5-flash-image",
+		"gemini-2.5-flash-image-preview": "gemini-2.5-flash-image",
 		"gemini-3.1-flash-image":         "gemini-3.1-flash-image",
 		"gemini-3.1-flash-image-preview": "gemini-3.1-flash-image",
 		"gemini-3-pro-image":             "gemini-3.1-flash-image",

backend/internal/handler/admin/account_handler.go

@@ -97,7 +97,7 @@ type CreateAccountRequest struct {
 	Name                    string         `json:"name" binding:"required"`
 	Notes                   *string        `json:"notes"`
 	Platform                string         `json:"platform" binding:"required"`
-	Type                    string         `json:"type" binding:"required,oneof=oauth setup-token apikey upstream"`
+	Type                    string         `json:"type" binding:"required,oneof=oauth setup-token apikey upstream bedrock"`
 	Credentials             map[string]any `json:"credentials" binding:"required"`
 	Extra                   map[string]any `json:"extra"`
 	ProxyID                 *int64         `json:"proxy_id"`
@@ -116,7 +116,7 @@ type CreateAccountRequest struct {
 type UpdateAccountRequest struct {
 	Name                    string         `json:"name"`
 	Notes                   *string        `json:"notes"`
-	Type                    string         `json:"type" binding:"omitempty,oneof=oauth setup-token apikey upstream"`
+	Type                    string         `json:"type" binding:"omitempty,oneof=oauth setup-token apikey upstream bedrock"`
 	Credentials             map[string]any `json:"credentials"`
 	Extra                   map[string]any `json:"extra"`
 	ProxyID                 *int64         `json:"proxy_id"`
@@ -165,6 +165,8 @@ type AccountWithConcurrency struct {
 	CurrentRPM        *int     `json:"current_rpm,omitempty"`         // 当前分钟 RPM 计数
 }
 
+const accountListGroupUngroupedQueryValue = "ungrouped"
+
 func (h *AccountHandler) buildAccountResponseWithRuntime(ctx context.Context, account *service.Account) AccountWithConcurrency {
 	item := AccountWithConcurrency{
 		Account:            dto.AccountFromService(account),
@@ -226,7 +228,20 @@ func (h *AccountHandler) List(c *gin.Context) {
 
 	var groupID int64
 	if groupIDStr := c.Query("group"); groupIDStr != "" {
-		groupID, _ = strconv.ParseInt(groupIDStr, 10, 64)
+		if groupIDStr == accountListGroupUngroupedQueryValue {
+			groupID = service.AccountListGroupUngrouped
+		} else {
+			parsedGroupID, parseErr := strconv.ParseInt(groupIDStr, 10, 64)
+			if parseErr != nil {
+				response.ErrorFrom(c, infraerrors.BadRequest("INVALID_GROUP_FILTER", "invalid group filter"))
+				return
+			}
+			if parsedGroupID < 0 {
+				response.ErrorFrom(c, infraerrors.BadRequest("INVALID_GROUP_FILTER", "invalid group filter"))
+				return
+			}
+			groupID = parsedGroupID
+		}
 	}
 
 	accounts, total, err := h.adminService.ListAccounts(c.Request.Context(), page, pageSize, platform, accountType, status, search, groupID)
@@ -628,6 +643,7 @@ func (h *AccountHandler) Delete(c *gin.Context) {
 // TestAccountRequest represents the request body for testing an account
 type TestAccountRequest struct {
 	ModelID string `json:"model_id"`
+	Prompt  string `json:"prompt"`
 }
 
 type SyncFromCRSRequest struct {
@@ -658,7 +674,7 @@ func (h *AccountHandler) Test(c *gin.Context) {
 	_ = c.ShouldBindJSON(&req)
 
 	// Use AccountTestService to test the account with SSE streaming
-	if err := h.accountTestService.TestAccountConnection(c, accountID, req.ModelID); err != nil {
+	if err := h.accountTestService.TestAccountConnection(c, accountID, req.ModelID, req.Prompt); err != nil {
 		// Error already sent via SSE, just log
 		return
 	}
@@ -864,6 +880,9 @@ func (h *AccountHandler) refreshSingleAccount(ctx context.Context, account *serv
 		}
 	}
 
+	// OpenAI OAuth: 刷新成功后检查并设置 privacy_mode
+	h.adminService.EnsureOpenAIPrivacy(ctx, updatedAccount)
+
 	return updatedAccount, "", nil
 }
 
@@ -1492,7 +1511,7 @@ func (h *OAuthHandler) SetupTokenCookieAuth(c *gin.Context) {
 }
 
 // GetUsage handles getting account usage information
-// GET /api/v1/admin/accounts/:id/usage
+// GET /api/v1/admin/accounts/:id/usage?source=passive|active
 func (h *AccountHandler) GetUsage(c *gin.Context) {
 	accountID, err := strconv.ParseInt(c.Param("id"), 10, 64)
 	if err != nil {
@@ -1500,7 +1519,14 @@ func (h *AccountHandler) GetUsage(c *gin.Context) {
 		return
 	}
 
-	usage, err := h.accountUsageService.GetUsage(c.Request.Context(), accountID)
+	source := c.DefaultQuery("source", "active")
+
+	var usage *service.UsageInfo
+	if source == "passive" {
+		usage, err = h.accountUsageService.GetPassiveUsage(c.Request.Context(), accountID)
+	} else {
+		usage, err = h.accountUsageService.GetUsage(c.Request.Context(), accountID)
+	}
 	if err != nil {
 		response.ErrorFrom(c, err)
 		return
@@ -1714,13 +1740,12 @@ func (h *AccountHandler) GetAvailableModels(c *gin.Context) {
 
 	// Handle OpenAI accounts
 	if account.IsOpenAI() {
-		// For OAuth accounts: return default OpenAI models
-		if account.IsOAuth() {
+		// OpenAI 自动透传会绕过常规模型改写，测试/模型列表也应回落到默认模型集。
+		if account.IsOpenAIPassthroughEnabled() {
 			response.Success(c, openai.DefaultModels)
 			return
 		}
 
-		// For API Key accounts: check model_mapping
 		mapping := account.GetModelMapping()
 		if len(mapping) == 0 {
 			response.Success(c, openai.DefaultModels)

backend/internal/handler/admin/account_handler_available_models_test.go

@@ -0,0 +1,105 @@
+package admin
+
+import (
+	"context"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/Wei-Shaw/sub2api/internal/service"
+	"github.com/gin-gonic/gin"
+	"github.com/stretchr/testify/require"
+)
+
+type availableModelsAdminService struct {
+	*stubAdminService
+	account service.Account
+}
+
+func (s *availableModelsAdminService) GetAccount(_ context.Context, id int64) (*service.Account, error) {
+	if s.account.ID == id {
+		acc := s.account
+		return &acc, nil
+	}
+	return s.stubAdminService.GetAccount(context.Background(), id)
+}
+
+func setupAvailableModelsRouter(adminSvc service.AdminService) *gin.Engine {
+	gin.SetMode(gin.TestMode)
+	router := gin.New()
+	handler := NewAccountHandler(adminSvc, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil)
+	router.GET("/api/v1/admin/accounts/:id/models", handler.GetAvailableModels)
+	return router
+}
+
+func TestAccountHandlerGetAvailableModels_OpenAIOAuthUsesExplicitModelMapping(t *testing.T) {
+	svc := &availableModelsAdminService{
+		stubAdminService: newStubAdminService(),
+		account: service.Account{
+			ID:       42,
+			Name:     "openai-oauth",
+			Platform: service.PlatformOpenAI,
+			Type:     service.AccountTypeOAuth,
+			Status:   service.StatusActive,
+			Credentials: map[string]any{
+				"model_mapping": map[string]any{
+					"gpt-5": "gpt-5.1",
+				},
+			},
+		},
+	}
+	router := setupAvailableModelsRouter(svc)
+
+	rec := httptest.NewRecorder()
+	req := httptest.NewRequest(http.MethodGet, "/api/v1/admin/accounts/42/models", nil)
+	router.ServeHTTP(rec, req)
+
+	require.Equal(t, http.StatusOK, rec.Code)
+
+	var resp struct {
+		Data []struct {
+			ID string `json:"id"`
+		} `json:"data"`
+	}
+	require.NoError(t, json.Unmarshal(rec.Body.Bytes(), &resp))
+	require.Len(t, resp.Data, 1)
+	require.Equal(t, "gpt-5", resp.Data[0].ID)
+}
+
+func TestAccountHandlerGetAvailableModels_OpenAIOAuthPassthroughFallsBackToDefaults(t *testing.T) {
+	svc := &availableModelsAdminService{
+		stubAdminService: newStubAdminService(),
+		account: service.Account{
+			ID:       43,
+			Name:     "openai-oauth-passthrough",
+			Platform: service.PlatformOpenAI,
+			Type:     service.AccountTypeOAuth,
+			Status:   service.StatusActive,
+			Credentials: map[string]any{
+				"model_mapping": map[string]any{
+					"gpt-5": "gpt-5.1",
+				},
+			},
+			Extra: map[string]any{
+				"openai_passthrough": true,
+			},
+		},
+	}
+	router := setupAvailableModelsRouter(svc)
+
+	rec := httptest.NewRecorder()
+	req := httptest.NewRequest(http.MethodGet, "/api/v1/admin/accounts/43/models", nil)
+	router.ServeHTTP(rec, req)
+
+	require.Equal(t, http.StatusOK, rec.Code)
+
+	var resp struct {
+		Data []struct {
+			ID string `json:"id"`
+		} `json:"data"`
+	}
+	require.NoError(t, json.Unmarshal(rec.Body.Bytes(), &resp))
+	require.NotEmpty(t, resp.Data)
+	require.NotEqual(t, "gpt-5", resp.Data[0].ID)
+}

backend/internal/handler/admin/admin_basic_handlers_test.go

@@ -17,7 +17,7 @@ func setupAdminRouter() (*gin.Engine, *stubAdminService) {
 	adminSvc := newStubAdminService()
 
 	userHandler := NewUserHandler(adminSvc, nil)
-	groupHandler := NewGroupHandler(adminSvc)
+	groupHandler := NewGroupHandler(adminSvc, nil, nil)
 	proxyHandler := NewProxyHandler(adminSvc)
 	redeemHandler := NewRedeemHandler(adminSvc, nil)
 

backend/internal/handler/admin/admin_service_stub_test.go

@@ -175,6 +175,18 @@ func (s *stubAdminService) GetGroupAPIKeys(ctx context.Context, groupID int64, p
 	return s.apiKeys, int64(len(s.apiKeys)), nil
 }
 
+func (s *stubAdminService) GetGroupRateMultipliers(_ context.Context, _ int64) ([]service.UserGroupRateEntry, error) {
+	return nil, nil
+}
+
+func (s *stubAdminService) ClearGroupRateMultipliers(_ context.Context, _ int64) error {
+	return nil
+}
+
+func (s *stubAdminService) BatchSetGroupRateMultipliers(_ context.Context, _ int64, _ []service.GroupRateMultiplierInput) error {
+	return nil
+}
+
 func (s *stubAdminService) ListAccounts(ctx context.Context, page, pageSize int, platform, accountType, status, search string, groupID int64) ([]service.Account, int64, error) {
 	return s.accounts, int64(len(s.accounts)), nil
 }
@@ -429,5 +441,9 @@ func (s *stubAdminService) ResetAccountQuota(ctx context.Context, id int64) erro
 	return nil
 }
 
+func (s *stubAdminService) EnsureOpenAIPrivacy(ctx context.Context, account *service.Account) string {
+	return ""
+}
+
 // Ensure stub implements interface.
 var _ service.AdminService = (*stubAdminService)(nil)

backend/internal/handler/admin/backup_handler.go

@@ -0,0 +1,205 @@
+package admin
+
+import (
+	"github.com/Wei-Shaw/sub2api/internal/pkg/response"
+	"github.com/Wei-Shaw/sub2api/internal/server/middleware"
+	"github.com/Wei-Shaw/sub2api/internal/service"
+	"github.com/gin-gonic/gin"
+)
+
+type BackupHandler struct {
+	backupService *service.BackupService
+	userService   *service.UserService
+}
+
+func NewBackupHandler(backupService *service.BackupService, userService *service.UserService) *BackupHandler {
+	return &BackupHandler{
+		backupService: backupService,
+		userService:   userService,
+	}
+}
+
+// ─── S3 配置 ───
+
+func (h *BackupHandler) GetS3Config(c *gin.Context) {
+	cfg, err := h.backupService.GetS3Config(c.Request.Context())
+	if err != nil {
+		response.ErrorFrom(c, err)
+		return
+	}
+	response.Success(c, cfg)
+}
+
+func (h *BackupHandler) UpdateS3Config(c *gin.Context) {
+	var req service.BackupS3Config
+	if err := c.ShouldBindJSON(&req); err != nil {
+		response.BadRequest(c, "Invalid request: "+err.Error())
+		return
+	}
+	cfg, err := h.backupService.UpdateS3Config(c.Request.Context(), req)
+	if err != nil {
+		response.ErrorFrom(c, err)
+		return
+	}
+	response.Success(c, cfg)
+}
+
+func (h *BackupHandler) TestS3Connection(c *gin.Context) {
+	var req service.BackupS3Config
+	if err := c.ShouldBindJSON(&req); err != nil {
+		response.BadRequest(c, "Invalid request: "+err.Error())
+		return
+	}
+	err := h.backupService.TestS3Connection(c.Request.Context(), req)
+	if err != nil {
+		response.Success(c, gin.H{"ok": false, "message": err.Error()})
+		return
+	}
+	response.Success(c, gin.H{"ok": true, "message": "connection successful"})
+}
+
+// ─── 定时备份 ───
+
+func (h *BackupHandler) GetSchedule(c *gin.Context) {
+	cfg, err := h.backupService.GetSchedule(c.Request.Context())
+	if err != nil {
+		response.ErrorFrom(c, err)
+		return
+	}
+	response.Success(c, cfg)
+}
+
+func (h *BackupHandler) UpdateSchedule(c *gin.Context) {
+	var req service.BackupScheduleConfig
+	if err := c.ShouldBindJSON(&req); err != nil {
+		response.BadRequest(c, "Invalid request: "+err.Error())
+		return
+	}
+	cfg, err := h.backupService.UpdateSchedule(c.Request.Context(), req)
+	if err != nil {
+		response.ErrorFrom(c, err)
+		return
+	}
+	response.Success(c, cfg)
+}
+
+// ─── 备份操作 ───
+
+type CreateBackupRequest struct {
+	ExpireDays *int `json:"expire_days"` // nil=使用默认值14，0=永不过期
+}
+
+func (h *BackupHandler) CreateBackup(c *gin.Context) {
+	var req CreateBackupRequest
+	_ = c.ShouldBindJSON(&req) // 允许空 body
+
+	expireDays := 14 // 默认14天过期
+	if req.ExpireDays != nil {
+		expireDays = *req.ExpireDays
+	}
+
+	record, err := h.backupService.StartBackup(c.Request.Context(), "manual", expireDays)
+	if err != nil {
+		response.ErrorFrom(c, err)
+		return
+	}
+	response.Accepted(c, record)
+}
+
+func (h *BackupHandler) ListBackups(c *gin.Context) {
+	records, err := h.backupService.ListBackups(c.Request.Context())
+	if err != nil {
+		response.ErrorFrom(c, err)
+		return
+	}
+	if records == nil {
+		records = []service.BackupRecord{}
+	}
+	response.Success(c, gin.H{"items": records})
+}
+
+func (h *BackupHandler) GetBackup(c *gin.Context) {
+	backupID := c.Param("id")
+	if backupID == "" {
+		response.BadRequest(c, "backup ID is required")
+		return
+	}
+	record, err := h.backupService.GetBackupRecord(c.Request.Context(), backupID)
+	if err != nil {
+		response.ErrorFrom(c, err)
+		return
+	}
+	response.Success(c, record)
+}
+
+func (h *BackupHandler) DeleteBackup(c *gin.Context) {
+	backupID := c.Param("id")
+	if backupID == "" {
+		response.BadRequest(c, "backup ID is required")
+		return
+	}
+	if err := h.backupService.DeleteBackup(c.Request.Context(), backupID); err != nil {
+		response.ErrorFrom(c, err)
+		return
+	}
+	response.Success(c, gin.H{"deleted": true})
+}
+
+func (h *BackupHandler) GetDownloadURL(c *gin.Context) {
+	backupID := c.Param("id")
+	if backupID == "" {
+		response.BadRequest(c, "backup ID is required")
+		return
+	}
+	url, err := h.backupService.GetBackupDownloadURL(c.Request.Context(), backupID)
+	if err != nil {
+		response.ErrorFrom(c, err)
+		return
+	}
+	response.Success(c, gin.H{"url": url})
+}
+
+// ─── 恢复操作（需要重新输入管理员密码） ───
+
+type RestoreBackupRequest struct {
+	Password string `json:"password" binding:"required"`
+}
+
+func (h *BackupHandler) RestoreBackup(c *gin.Context) {
+	backupID := c.Param("id")
+	if backupID == "" {
+		response.BadRequest(c, "backup ID is required")
+		return
+	}
+
+	var req RestoreBackupRequest
+	if err := c.ShouldBindJSON(&req); err != nil {
+		response.BadRequest(c, "password is required for restore operation")
+		return
+	}
+
+	// 从上下文获取当前管理员用户 ID
+	sub, ok := middleware.GetAuthSubjectFromContext(c)
+	if !ok {
+		response.Unauthorized(c, "unauthorized")
+		return
+	}
+
+	// 获取管理员用户并验证密码
+	user, err := h.userService.GetByID(c.Request.Context(), sub.UserID)
+	if err != nil {
+		response.ErrorFrom(c, err)
+		return
+	}
+	if !user.CheckPassword(req.Password) {
+		response.BadRequest(c, "incorrect admin password")
+		return
+	}
+
+	record, err := h.backupService.StartRestore(c.Request.Context(), backupID)
+	if err != nil {
+		response.ErrorFrom(c, err)
+		return
+	}
+	response.Accepted(c, record)
+}

backend/internal/handler/admin/dashboard_handler.go

@@ -9,6 +9,7 @@ import (
 
 	"github.com/Wei-Shaw/sub2api/internal/pkg/response"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/timezone"
+	"github.com/Wei-Shaw/sub2api/internal/pkg/usagestats"
 	"github.com/Wei-Shaw/sub2api/internal/service"
 
 	"github.com/gin-gonic/gin"
@@ -249,11 +250,12 @@ func (h *DashboardHandler) GetUsageTrend(c *gin.Context) {
 		}
 	}
 
-	trend, err := h.dashboardService.GetUsageTrendWithFilters(c.Request.Context(), startTime, endTime, granularity, userID, apiKeyID, accountID, groupID, model, requestType, stream, billingType)
+	trend, hit, err := h.getUsageTrendCached(c.Request.Context(), startTime, endTime, granularity, userID, apiKeyID, accountID, groupID, model, requestType, stream, billingType)
 	if err != nil {
 		response.Error(c, 500, "Failed to get usage trend")
 		return
 	}
+	c.Header("X-Snapshot-Cache", cacheStatusValue(hit))
 
 	response.Success(c, gin.H{
 		"trend":       trend,
@@ -271,6 +273,7 @@ func (h *DashboardHandler) GetModelStats(c *gin.Context) {
 
 	// Parse optional filter params
 	var userID, apiKeyID, accountID, groupID int64
+	modelSource := usagestats.ModelSourceRequested
 	var requestType *int16
 	var stream *bool
 	var billingType *int8
@@ -295,6 +298,13 @@ func (h *DashboardHandler) GetModelStats(c *gin.Context) {
 			groupID = id
 		}
 	}
+	if rawModelSource := strings.TrimSpace(c.Query("model_source")); rawModelSource != "" {
+		if !usagestats.IsValidModelSource(rawModelSource) {
+			response.BadRequest(c, "Invalid model_source, use requested/upstream/mapping")
+			return
+		}
+		modelSource = rawModelSource
+	}
 	if requestTypeStr := strings.TrimSpace(c.Query("request_type")); requestTypeStr != "" {
 		parsed, err := service.ParseUsageRequestType(requestTypeStr)
 		if err != nil {
@@ -321,11 +331,12 @@ func (h *DashboardHandler) GetModelStats(c *gin.Context) {
 		}
 	}
 
-	stats, err := h.dashboardService.GetModelStatsWithFilters(c.Request.Context(), startTime, endTime, userID, apiKeyID, accountID, groupID, requestType, stream, billingType)
+	stats, hit, err := h.getModelStatsCached(c.Request.Context(), startTime, endTime, userID, apiKeyID, accountID, groupID, modelSource, requestType, stream, billingType)
 	if err != nil {
 		response.Error(c, 500, "Failed to get model statistics")
 		return
 	}
+	c.Header("X-Snapshot-Cache", cacheStatusValue(hit))
 
 	response.Success(c, gin.H{
 		"models":     stats,
@@ -391,11 +402,12 @@ func (h *DashboardHandler) GetGroupStats(c *gin.Context) {
 		}
 	}
 
-	stats, err := h.dashboardService.GetGroupStatsWithFilters(c.Request.Context(), startTime, endTime, userID, apiKeyID, accountID, groupID, requestType, stream, billingType)
+	stats, hit, err := h.getGroupStatsCached(c.Request.Context(), startTime, endTime, userID, apiKeyID, accountID, groupID, requestType, stream, billingType)
 	if err != nil {
 		response.Error(c, 500, "Failed to get group statistics")
 		return
 	}
+	c.Header("X-Snapshot-Cache", cacheStatusValue(hit))
 
 	response.Success(c, gin.H{
 		"groups":     stats,
@@ -416,11 +428,12 @@ func (h *DashboardHandler) GetAPIKeyUsageTrend(c *gin.Context) {
 		limit = 5
 	}
 
-	trend, err := h.dashboardService.GetAPIKeyUsageTrend(c.Request.Context(), startTime, endTime, granularity, limit)
+	trend, hit, err := h.getAPIKeyUsageTrendCached(c.Request.Context(), startTime, endTime, granularity, limit)
 	if err != nil {
 		response.Error(c, 500, "Failed to get API key usage trend")
 		return
 	}
+	c.Header("X-Snapshot-Cache", cacheStatusValue(hit))
 
 	response.Success(c, gin.H{
 		"trend":       trend,
@@ -442,11 +455,12 @@ func (h *DashboardHandler) GetUserUsageTrend(c *gin.Context) {
 		limit = 12
 	}
 
-	trend, err := h.dashboardService.GetUserUsageTrend(c.Request.Context(), startTime, endTime, granularity, limit)
+	trend, hit, err := h.getUserUsageTrendCached(c.Request.Context(), startTime, endTime, granularity, limit)
 	if err != nil {
 		response.Error(c, 500, "Failed to get user usage trend")
 		return
 	}
+	c.Header("X-Snapshot-Cache", cacheStatusValue(hit))
 
 	response.Success(c, gin.H{
 		"trend":       trend,
@@ -461,9 +475,62 @@ type BatchUsersUsageRequest struct {
 	UserIDs []int64 `json:"user_ids" binding:"required"`
 }
 
+var dashboardUsersRankingCache = newSnapshotCache(5 * time.Minute)
 var dashboardBatchUsersUsageCache = newSnapshotCache(30 * time.Second)
 var dashboardBatchAPIKeysUsageCache = newSnapshotCache(30 * time.Second)
 
+func parseRankingLimit(raw string) int {
+	limit, err := strconv.Atoi(strings.TrimSpace(raw))
+	if err != nil || limit <= 0 {
+		return 12
+	}
+	if limit > 50 {
+		return 50
+	}
+	return limit
+}
+
+// GetUserSpendingRanking handles getting user spending ranking data.
+// GET /api/v1/admin/dashboard/users-ranking
+func (h *DashboardHandler) GetUserSpendingRanking(c *gin.Context) {
+	startTime, endTime := parseTimeRange(c)
+	limit := parseRankingLimit(c.DefaultQuery("limit", "12"))
+
+	keyRaw, _ := json.Marshal(struct {
+		Start string `json:"start"`
+		End   string `json:"end"`
+		Limit int    `json:"limit"`
+	}{
+		Start: startTime.UTC().Format(time.RFC3339),
+		End:   endTime.UTC().Format(time.RFC3339),
+		Limit: limit,
+	})
+	cacheKey := string(keyRaw)
+	if cached, ok := dashboardUsersRankingCache.Get(cacheKey); ok {
+		c.Header("X-Snapshot-Cache", "hit")
+		response.Success(c, cached.Payload)
+		return
+	}
+
+	ranking, err := h.dashboardService.GetUserSpendingRanking(c.Request.Context(), startTime, endTime, limit)
+	if err != nil {
+		response.Error(c, 500, "Failed to get user spending ranking")
+		return
+	}
+
+	payload := gin.H{
+		"ranking":           ranking.Ranking,
+		"total_actual_cost": ranking.TotalActualCost,
+		"total_requests":    ranking.TotalRequests,
+		"total_tokens":      ranking.TotalTokens,
+		"start_date":        startTime.Format("2006-01-02"),
+		"end_date":          endTime.Add(-24 * time.Hour).Format("2006-01-02"),
+	}
+	dashboardUsersRankingCache.Set(cacheKey, payload)
+	c.Header("X-Snapshot-Cache", "miss")
+	response.Success(c, payload)
+}
+
 // GetBatchUsersUsage handles getting usage stats for multiple users
 // POST /api/v1/admin/dashboard/users-usage
 func (h *DashboardHandler) GetBatchUsersUsage(c *gin.Context) {
@@ -546,3 +613,47 @@ func (h *DashboardHandler) GetBatchAPIKeysUsage(c *gin.Context) {
 	c.Header("X-Snapshot-Cache", "miss")
 	response.Success(c, payload)
 }
+
+// GetUserBreakdown handles getting per-user usage breakdown within a dimension.
+// GET /api/v1/admin/dashboard/user-breakdown
+// Query params: start_date, end_date, group_id, model, endpoint, endpoint_type, limit
+func (h *DashboardHandler) GetUserBreakdown(c *gin.Context) {
+	startTime, endTime := parseTimeRange(c)
+
+	dim := usagestats.UserBreakdownDimension{}
+	if v := c.Query("group_id"); v != "" {
+		if id, err := strconv.ParseInt(v, 10, 64); err == nil {
+			dim.GroupID = id
+		}
+	}
+	dim.Model = c.Query("model")
+	rawModelSource := strings.TrimSpace(c.DefaultQuery("model_source", usagestats.ModelSourceRequested))
+	if !usagestats.IsValidModelSource(rawModelSource) {
+		response.BadRequest(c, "Invalid model_source, use requested/upstream/mapping")
+		return
+	}
+	dim.ModelType = rawModelSource
+	dim.Endpoint = c.Query("endpoint")
+	dim.EndpointType = c.DefaultQuery("endpoint_type", "inbound")
+
+	limit := 50
+	if v := c.Query("limit"); v != "" {
+		if n, err := strconv.Atoi(v); err == nil && n > 0 && n <= 200 {
+			limit = n
+		}
+	}
+
+	stats, err := h.dashboardService.GetUserBreakdownStats(
+		c.Request.Context(), startTime, endTime, dim, limit,
+	)
+	if err != nil {
+		response.Error(c, 500, "Failed to get user breakdown stats")
+		return
+	}
+
+	response.Success(c, gin.H{
+		"users":      stats,
+		"start_date": startTime.Format("2006-01-02"),
+		"end_date":   endTime.Add(-24 * time.Hour).Format("2006-01-02"),
+	})
+}

backend/internal/handler/admin/dashboard_handler_cache_test.go

@@ -0,0 +1,118 @@
+package admin
+
+import (
+	"context"
+	"net/http"
+	"net/http/httptest"
+	"sync/atomic"
+	"testing"
+	"time"
+
+	"github.com/Wei-Shaw/sub2api/internal/pkg/usagestats"
+	"github.com/Wei-Shaw/sub2api/internal/service"
+	"github.com/gin-gonic/gin"
+	"github.com/stretchr/testify/require"
+)
+
+type dashboardUsageRepoCacheProbe struct {
+	service.UsageLogRepository
+	trendCalls      atomic.Int32
+	usersTrendCalls atomic.Int32
+}
+
+func (r *dashboardUsageRepoCacheProbe) GetUsageTrendWithFilters(
+	ctx context.Context,
+	startTime, endTime time.Time,
+	granularity string,
+	userID, apiKeyID, accountID, groupID int64,
+	model string,
+	requestType *int16,
+	stream *bool,
+	billingType *int8,
+) ([]usagestats.TrendDataPoint, error) {
+	r.trendCalls.Add(1)
+	return []usagestats.TrendDataPoint{{
+		Date:        "2026-03-11",
+		Requests:    1,
+		TotalTokens: 2,
+		Cost:        3,
+		ActualCost:  4,
+	}}, nil
+}
+
+func (r *dashboardUsageRepoCacheProbe) GetUserUsageTrend(
+	ctx context.Context,
+	startTime, endTime time.Time,
+	granularity string,
+	limit int,
+) ([]usagestats.UserUsageTrendPoint, error) {
+	r.usersTrendCalls.Add(1)
+	return []usagestats.UserUsageTrendPoint{{
+		Date:       "2026-03-11",
+		UserID:     1,
+		Email:      "cache@test.dev",
+		Requests:   2,
+		Tokens:     20,
+		Cost:       2,
+		ActualCost: 1,
+	}}, nil
+}
+
+func resetDashboardReadCachesForTest() {
+	dashboardTrendCache = newSnapshotCache(30 * time.Second)
+	dashboardUsersTrendCache = newSnapshotCache(30 * time.Second)
+	dashboardAPIKeysTrendCache = newSnapshotCache(30 * time.Second)
+	dashboardModelStatsCache = newSnapshotCache(30 * time.Second)
+	dashboardGroupStatsCache = newSnapshotCache(30 * time.Second)
+	dashboardSnapshotV2Cache = newSnapshotCache(30 * time.Second)
+}
+
+func TestDashboardHandler_GetUsageTrend_UsesCache(t *testing.T) {
+	t.Cleanup(resetDashboardReadCachesForTest)
+	resetDashboardReadCachesForTest()
+
+	gin.SetMode(gin.TestMode)
+	repo := &dashboardUsageRepoCacheProbe{}
+	dashboardSvc := service.NewDashboardService(repo, nil, nil, nil)
+	handler := NewDashboardHandler(dashboardSvc, nil)
+	router := gin.New()
+	router.GET("/admin/dashboard/trend", handler.GetUsageTrend)
+
+	req1 := httptest.NewRequest(http.MethodGet, "/admin/dashboard/trend?start_date=2026-03-01&end_date=2026-03-07&granularity=day", nil)
+	rec1 := httptest.NewRecorder()
+	router.ServeHTTP(rec1, req1)
+	require.Equal(t, http.StatusOK, rec1.Code)
+	require.Equal(t, "miss", rec1.Header().Get("X-Snapshot-Cache"))
+
+	req2 := httptest.NewRequest(http.MethodGet, "/admin/dashboard/trend?start_date=2026-03-01&end_date=2026-03-07&granularity=day", nil)
+	rec2 := httptest.NewRecorder()
+	router.ServeHTTP(rec2, req2)
+	require.Equal(t, http.StatusOK, rec2.Code)
+	require.Equal(t, "hit", rec2.Header().Get("X-Snapshot-Cache"))
+	require.Equal(t, int32(1), repo.trendCalls.Load())
+}
+
+func TestDashboardHandler_GetUserUsageTrend_UsesCache(t *testing.T) {
+	t.Cleanup(resetDashboardReadCachesForTest)
+	resetDashboardReadCachesForTest()
+
+	gin.SetMode(gin.TestMode)
+	repo := &dashboardUsageRepoCacheProbe{}
+	dashboardSvc := service.NewDashboardService(repo, nil, nil, nil)
+	handler := NewDashboardHandler(dashboardSvc, nil)
+	router := gin.New()
+	router.GET("/admin/dashboard/users-trend", handler.GetUserUsageTrend)
+
+	req1 := httptest.NewRequest(http.MethodGet, "/admin/dashboard/users-trend?start_date=2026-03-01&end_date=2026-03-07&granularity=day&limit=8", nil)
+	rec1 := httptest.NewRecorder()
+	router.ServeHTTP(rec1, req1)
+	require.Equal(t, http.StatusOK, rec1.Code)
+	require.Equal(t, "miss", rec1.Header().Get("X-Snapshot-Cache"))
+
+	req2 := httptest.NewRequest(http.MethodGet, "/admin/dashboard/users-trend?start_date=2026-03-01&end_date=2026-03-07&granularity=day&limit=8", nil)
+	rec2 := httptest.NewRecorder()
+	router.ServeHTTP(rec2, req2)
+	require.Equal(t, http.StatusOK, rec2.Code)
+	require.Equal(t, "hit", rec2.Header().Get("X-Snapshot-Cache"))
+	require.Equal(t, int32(1), repo.usersTrendCalls.Load())
+}

backend/internal/handler/admin/dashboard_handler_request_type_test.go

@@ -19,6 +19,9 @@ type dashboardUsageRepoCapture struct {
 	trendStream      *bool
 	modelRequestType *int16
 	modelStream      *bool
+	rankingLimit     int
+	ranking          []usagestats.UserSpendingRankingItem
+	rankingTotal     float64
 }
 
 func (s *dashboardUsageRepoCapture) GetUsageTrendWithFilters(
@@ -49,6 +52,20 @@ func (s *dashboardUsageRepoCapture) GetModelStatsWithFilters(
 	return []usagestats.ModelStat{}, nil
 }
 
+func (s *dashboardUsageRepoCapture) GetUserSpendingRanking(
+	ctx context.Context,
+	startTime, endTime time.Time,
+	limit int,
+) (*usagestats.UserSpendingRankingResponse, error) {
+	s.rankingLimit = limit
+	return &usagestats.UserSpendingRankingResponse{
+		Ranking:         s.ranking,
+		TotalActualCost: s.rankingTotal,
+		TotalRequests:   44,
+		TotalTokens:     1234,
+	}, nil
+}
+
 func newDashboardRequestTypeTestRouter(repo *dashboardUsageRepoCapture) *gin.Engine {
 	gin.SetMode(gin.TestMode)
 	dashboardSvc := service.NewDashboardService(repo, nil, nil, nil)
@@ -56,6 +73,7 @@ func newDashboardRequestTypeTestRouter(repo *dashboardUsageRepoCapture) *gin.Eng
 	router := gin.New()
 	router.GET("/admin/dashboard/trend", handler.GetUsageTrend)
 	router.GET("/admin/dashboard/models", handler.GetModelStats)
+	router.GET("/admin/dashboard/users-ranking", handler.GetUserSpendingRanking)
 	return router
 }
 
@@ -130,3 +148,54 @@ func TestDashboardModelStatsInvalidStream(t *testing.T) {
 
 	require.Equal(t, http.StatusBadRequest, rec.Code)
 }
+
+func TestDashboardModelStatsInvalidModelSource(t *testing.T) {
+	repo := &dashboardUsageRepoCapture{}
+	router := newDashboardRequestTypeTestRouter(repo)
+
+	req := httptest.NewRequest(http.MethodGet, "/admin/dashboard/models?model_source=invalid", nil)
+	rec := httptest.NewRecorder()
+	router.ServeHTTP(rec, req)
+
+	require.Equal(t, http.StatusBadRequest, rec.Code)
+}
+
+func TestDashboardModelStatsValidModelSource(t *testing.T) {
+	repo := &dashboardUsageRepoCapture{}
+	router := newDashboardRequestTypeTestRouter(repo)
+
+	req := httptest.NewRequest(http.MethodGet, "/admin/dashboard/models?model_source=upstream", nil)
+	rec := httptest.NewRecorder()
+	router.ServeHTTP(rec, req)
+
+	require.Equal(t, http.StatusOK, rec.Code)
+}
+
+func TestDashboardUsersRankingLimitAndCache(t *testing.T) {
+	dashboardUsersRankingCache = newSnapshotCache(5 * time.Minute)
+	repo := &dashboardUsageRepoCapture{
+		ranking: []usagestats.UserSpendingRankingItem{
+			{UserID: 7, Email: "rank@example.com", ActualCost: 10.5, Requests: 3, Tokens: 300},
+		},
+		rankingTotal: 88.8,
+	}
+	router := newDashboardRequestTypeTestRouter(repo)
+
+	req := httptest.NewRequest(http.MethodGet, "/admin/dashboard/users-ranking?limit=100&start_date=2025-01-01&end_date=2025-01-02", nil)
+	rec := httptest.NewRecorder()
+	router.ServeHTTP(rec, req)
+
+	require.Equal(t, http.StatusOK, rec.Code)
+	require.Equal(t, 50, repo.rankingLimit)
+	require.Contains(t, rec.Body.String(), "\"total_actual_cost\":88.8")
+	require.Contains(t, rec.Body.String(), "\"total_requests\":44")
+	require.Contains(t, rec.Body.String(), "\"total_tokens\":1234")
+	require.Equal(t, "miss", rec.Header().Get("X-Snapshot-Cache"))
+
+	req2 := httptest.NewRequest(http.MethodGet, "/admin/dashboard/users-ranking?limit=100&start_date=2025-01-01&end_date=2025-01-02", nil)
+	rec2 := httptest.NewRecorder()
+	router.ServeHTTP(rec2, req2)
+
+	require.Equal(t, http.StatusOK, rec2.Code)
+	require.Equal(t, "hit", rec2.Header().Get("X-Snapshot-Cache"))
+}

backend/internal/handler/admin/dashboard_handler_user_breakdown_test.go

@@ -0,0 +1,229 @@
+package admin
+
+import (
+	"context"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+	"time"
+
+	"github.com/Wei-Shaw/sub2api/internal/pkg/usagestats"
+	"github.com/Wei-Shaw/sub2api/internal/service"
+	"github.com/gin-gonic/gin"
+	"github.com/stretchr/testify/require"
+)
+
+// --- mock repo ---
+
+type userBreakdownRepoCapture struct {
+	service.UsageLogRepository
+	capturedDim   usagestats.UserBreakdownDimension
+	capturedLimit int
+	result        []usagestats.UserBreakdownItem
+}
+
+func (r *userBreakdownRepoCapture) GetUserBreakdownStats(
+	_ context.Context, _, _ time.Time,
+	dim usagestats.UserBreakdownDimension, limit int,
+) ([]usagestats.UserBreakdownItem, error) {
+	r.capturedDim = dim
+	r.capturedLimit = limit
+	if r.result != nil {
+		return r.result, nil
+	}
+	return []usagestats.UserBreakdownItem{}, nil
+}
+
+func newUserBreakdownRouter(repo *userBreakdownRepoCapture) *gin.Engine {
+	gin.SetMode(gin.TestMode)
+	svc := service.NewDashboardService(repo, nil, nil, nil)
+	h := NewDashboardHandler(svc, nil)
+	router := gin.New()
+	router.GET("/admin/dashboard/user-breakdown", h.GetUserBreakdown)
+	return router
+}
+
+// --- tests ---
+
+func TestGetUserBreakdown_GroupIDFilter(t *testing.T) {
+	repo := &userBreakdownRepoCapture{}
+	router := newUserBreakdownRouter(repo)
+
+	req := httptest.NewRequest(http.MethodGet,
+		"/admin/dashboard/user-breakdown?start_date=2026-03-01&end_date=2026-03-16&group_id=42", nil)
+	w := httptest.NewRecorder()
+	router.ServeHTTP(w, req)
+
+	require.Equal(t, http.StatusOK, w.Code)
+	require.Equal(t, int64(42), repo.capturedDim.GroupID)
+	require.Empty(t, repo.capturedDim.Model)
+	require.Empty(t, repo.capturedDim.Endpoint)
+	require.Equal(t, 50, repo.capturedLimit) // default limit
+}
+
+func TestGetUserBreakdown_ModelFilter(t *testing.T) {
+	repo := &userBreakdownRepoCapture{}
+	router := newUserBreakdownRouter(repo)
+
+	req := httptest.NewRequest(http.MethodGet,
+		"/admin/dashboard/user-breakdown?start_date=2026-03-01&end_date=2026-03-16&model=claude-opus-4-6", nil)
+	w := httptest.NewRecorder()
+	router.ServeHTTP(w, req)
+
+	require.Equal(t, http.StatusOK, w.Code)
+	require.Equal(t, "claude-opus-4-6", repo.capturedDim.Model)
+	require.Equal(t, usagestats.ModelSourceRequested, repo.capturedDim.ModelType)
+	require.Equal(t, int64(0), repo.capturedDim.GroupID)
+}
+
+func TestGetUserBreakdown_ModelSourceFilter(t *testing.T) {
+	repo := &userBreakdownRepoCapture{}
+	router := newUserBreakdownRouter(repo)
+
+	req := httptest.NewRequest(http.MethodGet,
+		"/admin/dashboard/user-breakdown?start_date=2026-03-01&end_date=2026-03-16&model=claude-opus-4-6&model_source=upstream", nil)
+	w := httptest.NewRecorder()
+	router.ServeHTTP(w, req)
+
+	require.Equal(t, http.StatusOK, w.Code)
+	require.Equal(t, usagestats.ModelSourceUpstream, repo.capturedDim.ModelType)
+}
+
+func TestGetUserBreakdown_InvalidModelSource(t *testing.T) {
+	repo := &userBreakdownRepoCapture{}
+	router := newUserBreakdownRouter(repo)
+
+	req := httptest.NewRequest(http.MethodGet,
+		"/admin/dashboard/user-breakdown?start_date=2026-03-01&end_date=2026-03-16&model_source=foobar", nil)
+	w := httptest.NewRecorder()
+	router.ServeHTTP(w, req)
+
+	require.Equal(t, http.StatusBadRequest, w.Code)
+}
+
+func TestGetUserBreakdown_EndpointFilter(t *testing.T) {
+	repo := &userBreakdownRepoCapture{}
+	router := newUserBreakdownRouter(repo)
+
+	req := httptest.NewRequest(http.MethodGet,
+		"/admin/dashboard/user-breakdown?start_date=2026-03-01&end_date=2026-03-16&endpoint=/v1/messages&endpoint_type=upstream", nil)
+	w := httptest.NewRecorder()
+	router.ServeHTTP(w, req)
+
+	require.Equal(t, http.StatusOK, w.Code)
+	require.Equal(t, "/v1/messages", repo.capturedDim.Endpoint)
+	require.Equal(t, "upstream", repo.capturedDim.EndpointType)
+}
+
+func TestGetUserBreakdown_DefaultEndpointType(t *testing.T) {
+	repo := &userBreakdownRepoCapture{}
+	router := newUserBreakdownRouter(repo)
+
+	req := httptest.NewRequest(http.MethodGet,
+		"/admin/dashboard/user-breakdown?start_date=2026-03-01&end_date=2026-03-16&endpoint=/chat", nil)
+	w := httptest.NewRecorder()
+	router.ServeHTTP(w, req)
+
+	require.Equal(t, http.StatusOK, w.Code)
+	require.Equal(t, "inbound", repo.capturedDim.EndpointType)
+}
+
+func TestGetUserBreakdown_CustomLimit(t *testing.T) {
+	repo := &userBreakdownRepoCapture{}
+	router := newUserBreakdownRouter(repo)
+
+	req := httptest.NewRequest(http.MethodGet,
+		"/admin/dashboard/user-breakdown?start_date=2026-03-01&end_date=2026-03-16&model=test&limit=100", nil)
+	w := httptest.NewRecorder()
+	router.ServeHTTP(w, req)
+
+	require.Equal(t, http.StatusOK, w.Code)
+	require.Equal(t, 100, repo.capturedLimit)
+}
+
+func TestGetUserBreakdown_LimitClamped(t *testing.T) {
+	repo := &userBreakdownRepoCapture{}
+	router := newUserBreakdownRouter(repo)
+
+	// limit > 200 should fall back to default 50
+	req := httptest.NewRequest(http.MethodGet,
+		"/admin/dashboard/user-breakdown?start_date=2026-03-01&end_date=2026-03-16&model=test&limit=999", nil)
+	w := httptest.NewRecorder()
+	router.ServeHTTP(w, req)
+
+	require.Equal(t, http.StatusOK, w.Code)
+	require.Equal(t, 50, repo.capturedLimit)
+}
+
+func TestGetUserBreakdown_ResponseFormat(t *testing.T) {
+	repo := &userBreakdownRepoCapture{
+		result: []usagestats.UserBreakdownItem{
+			{UserID: 1, Email: "alice@test.com", Requests: 100, TotalTokens: 50000, Cost: 1.5, ActualCost: 1.2},
+			{UserID: 2, Email: "bob@test.com", Requests: 50, TotalTokens: 25000, Cost: 0.8, ActualCost: 0.6},
+		},
+	}
+	router := newUserBreakdownRouter(repo)
+
+	req := httptest.NewRequest(http.MethodGet,
+		"/admin/dashboard/user-breakdown?start_date=2026-03-01&end_date=2026-03-16&group_id=1", nil)
+	w := httptest.NewRecorder()
+	router.ServeHTTP(w, req)
+
+	require.Equal(t, http.StatusOK, w.Code)
+
+	var resp struct {
+		Code int `json:"code"`
+		Data struct {
+			Users     []usagestats.UserBreakdownItem `json:"users"`
+			StartDate string                         `json:"start_date"`
+			EndDate   string                         `json:"end_date"`
+		} `json:"data"`
+	}
+	err := json.Unmarshal(w.Body.Bytes(), &resp)
+	require.NoError(t, err)
+	require.Equal(t, 0, resp.Code)
+	require.Len(t, resp.Data.Users, 2)
+	require.Equal(t, int64(1), resp.Data.Users[0].UserID)
+	require.Equal(t, "alice@test.com", resp.Data.Users[0].Email)
+	require.Equal(t, int64(100), resp.Data.Users[0].Requests)
+	require.InDelta(t, 1.2, resp.Data.Users[0].ActualCost, 0.001)
+	require.Equal(t, "2026-03-01", resp.Data.StartDate)
+	require.Equal(t, "2026-03-16", resp.Data.EndDate)
+}
+
+func TestGetUserBreakdown_EmptyResult(t *testing.T) {
+	repo := &userBreakdownRepoCapture{}
+	router := newUserBreakdownRouter(repo)
+
+	req := httptest.NewRequest(http.MethodGet,
+		"/admin/dashboard/user-breakdown?start_date=2026-03-01&end_date=2026-03-16&group_id=999", nil)
+	w := httptest.NewRecorder()
+	router.ServeHTTP(w, req)
+
+	require.Equal(t, http.StatusOK, w.Code)
+
+	var resp struct {
+		Data struct {
+			Users []usagestats.UserBreakdownItem `json:"users"`
+		} `json:"data"`
+	}
+	err := json.Unmarshal(w.Body.Bytes(), &resp)
+	require.NoError(t, err)
+	require.Empty(t, resp.Data.Users)
+}
+
+func TestGetUserBreakdown_NoFilters(t *testing.T) {
+	repo := &userBreakdownRepoCapture{}
+	router := newUserBreakdownRouter(repo)
+
+	req := httptest.NewRequest(http.MethodGet,
+		"/admin/dashboard/user-breakdown?start_date=2026-03-01&end_date=2026-03-16", nil)
+	w := httptest.NewRecorder()
+	router.ServeHTTP(w, req)
+
+	require.Equal(t, http.StatusOK, w.Code)
+	require.Equal(t, int64(0), repo.capturedDim.GroupID)
+	require.Empty(t, repo.capturedDim.Model)
+	require.Empty(t, repo.capturedDim.Endpoint)
+}

backend/internal/handler/admin/dashboard_query_cache.go

@@ -0,0 +1,203 @@
+package admin
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"time"
+
+	"github.com/Wei-Shaw/sub2api/internal/pkg/usagestats"
+)
+
+var (
+	dashboardTrendCache        = newSnapshotCache(30 * time.Second)
+	dashboardModelStatsCache   = newSnapshotCache(30 * time.Second)
+	dashboardGroupStatsCache   = newSnapshotCache(30 * time.Second)
+	dashboardUsersTrendCache   = newSnapshotCache(30 * time.Second)
+	dashboardAPIKeysTrendCache = newSnapshotCache(30 * time.Second)
+)
+
+type dashboardTrendCacheKey struct {
+	StartTime   string `json:"start_time"`
+	EndTime     string `json:"end_time"`
+	Granularity string `json:"granularity"`
+	UserID      int64  `json:"user_id"`
+	APIKeyID    int64  `json:"api_key_id"`
+	AccountID   int64  `json:"account_id"`
+	GroupID     int64  `json:"group_id"`
+	Model       string `json:"model"`
+	RequestType *int16 `json:"request_type"`
+	Stream      *bool  `json:"stream"`
+	BillingType *int8  `json:"billing_type"`
+}
+
+type dashboardModelGroupCacheKey struct {
+	StartTime   string `json:"start_time"`
+	EndTime     string `json:"end_time"`
+	UserID      int64  `json:"user_id"`
+	APIKeyID    int64  `json:"api_key_id"`
+	AccountID   int64  `json:"account_id"`
+	GroupID     int64  `json:"group_id"`
+	ModelSource string `json:"model_source,omitempty"`
+	RequestType *int16 `json:"request_type"`
+	Stream      *bool  `json:"stream"`
+	BillingType *int8  `json:"billing_type"`
+}
+
+type dashboardEntityTrendCacheKey struct {
+	StartTime   string `json:"start_time"`
+	EndTime     string `json:"end_time"`
+	Granularity string `json:"granularity"`
+	Limit       int    `json:"limit"`
+}
+
+func cacheStatusValue(hit bool) string {
+	if hit {
+		return "hit"
+	}
+	return "miss"
+}
+
+func mustMarshalDashboardCacheKey(value any) string {
+	raw, err := json.Marshal(value)
+	if err != nil {
+		return ""
+	}
+	return string(raw)
+}
+
+func snapshotPayloadAs[T any](payload any) (T, error) {
+	typed, ok := payload.(T)
+	if !ok {
+		var zero T
+		return zero, fmt.Errorf("unexpected cache payload type %T", payload)
+	}
+	return typed, nil
+}
+
+func (h *DashboardHandler) getUsageTrendCached(
+	ctx context.Context,
+	startTime, endTime time.Time,
+	granularity string,
+	userID, apiKeyID, accountID, groupID int64,
+	model string,
+	requestType *int16,
+	stream *bool,
+	billingType *int8,
+) ([]usagestats.TrendDataPoint, bool, error) {
+	key := mustMarshalDashboardCacheKey(dashboardTrendCacheKey{
+		StartTime:   startTime.UTC().Format(time.RFC3339),
+		EndTime:     endTime.UTC().Format(time.RFC3339),
+		Granularity: granularity,
+		UserID:      userID,
+		APIKeyID:    apiKeyID,
+		AccountID:   accountID,
+		GroupID:     groupID,
+		Model:       model,
+		RequestType: requestType,
+		Stream:      stream,
+		BillingType: billingType,
+	})
+	entry, hit, err := dashboardTrendCache.GetOrLoad(key, func() (any, error) {
+		return h.dashboardService.GetUsageTrendWithFilters(ctx, startTime, endTime, granularity, userID, apiKeyID, accountID, groupID, model, requestType, stream, billingType)
+	})
+	if err != nil {
+		return nil, hit, err
+	}
+	trend, err := snapshotPayloadAs[[]usagestats.TrendDataPoint](entry.Payload)
+	return trend, hit, err
+}
+
+func (h *DashboardHandler) getModelStatsCached(
+	ctx context.Context,
+	startTime, endTime time.Time,
+	userID, apiKeyID, accountID, groupID int64,
+	modelSource string,
+	requestType *int16,
+	stream *bool,
+	billingType *int8,
+) ([]usagestats.ModelStat, bool, error) {
+	key := mustMarshalDashboardCacheKey(dashboardModelGroupCacheKey{
+		StartTime:   startTime.UTC().Format(time.RFC3339),
+		EndTime:     endTime.UTC().Format(time.RFC3339),
+		UserID:      userID,
+		APIKeyID:    apiKeyID,
+		AccountID:   accountID,
+		GroupID:     groupID,
+		ModelSource: usagestats.NormalizeModelSource(modelSource),
+		RequestType: requestType,
+		Stream:      stream,
+		BillingType: billingType,
+	})
+	entry, hit, err := dashboardModelStatsCache.GetOrLoad(key, func() (any, error) {
+		return h.dashboardService.GetModelStatsWithFiltersBySource(ctx, startTime, endTime, userID, apiKeyID, accountID, groupID, requestType, stream, billingType, modelSource)
+	})
+	if err != nil {
+		return nil, hit, err
+	}
+	stats, err := snapshotPayloadAs[[]usagestats.ModelStat](entry.Payload)
+	return stats, hit, err
+}
+
+func (h *DashboardHandler) getGroupStatsCached(
+	ctx context.Context,
+	startTime, endTime time.Time,
+	userID, apiKeyID, accountID, groupID int64,
+	requestType *int16,
+	stream *bool,
+	billingType *int8,
+) ([]usagestats.GroupStat, bool, error) {
+	key := mustMarshalDashboardCacheKey(dashboardModelGroupCacheKey{
+		StartTime:   startTime.UTC().Format(time.RFC3339),
+		EndTime:     endTime.UTC().Format(time.RFC3339),
+		UserID:      userID,
+		APIKeyID:    apiKeyID,
+		AccountID:   accountID,
+		GroupID:     groupID,
+		RequestType: requestType,
+		Stream:      stream,
+		BillingType: billingType,
+	})
+	entry, hit, err := dashboardGroupStatsCache.GetOrLoad(key, func() (any, error) {
+		return h.dashboardService.GetGroupStatsWithFilters(ctx, startTime, endTime, userID, apiKeyID, accountID, groupID, requestType, stream, billingType)
+	})
+	if err != nil {
+		return nil, hit, err
+	}
+	stats, err := snapshotPayloadAs[[]usagestats.GroupStat](entry.Payload)
+	return stats, hit, err
+}
+
+func (h *DashboardHandler) getAPIKeyUsageTrendCached(ctx context.Context, startTime, endTime time.Time, granularity string, limit int) ([]usagestats.APIKeyUsageTrendPoint, bool, error) {
+	key := mustMarshalDashboardCacheKey(dashboardEntityTrendCacheKey{
+		StartTime:   startTime.UTC().Format(time.RFC3339),
+		EndTime:     endTime.UTC().Format(time.RFC3339),
+		Granularity: granularity,
+		Limit:       limit,
+	})
+	entry, hit, err := dashboardAPIKeysTrendCache.GetOrLoad(key, func() (any, error) {
+		return h.dashboardService.GetAPIKeyUsageTrend(ctx, startTime, endTime, granularity, limit)
+	})
+	if err != nil {
+		return nil, hit, err
+	}
+	trend, err := snapshotPayloadAs[[]usagestats.APIKeyUsageTrendPoint](entry.Payload)
+	return trend, hit, err
+}
+
+func (h *DashboardHandler) getUserUsageTrendCached(ctx context.Context, startTime, endTime time.Time, granularity string, limit int) ([]usagestats.UserUsageTrendPoint, bool, error) {
+	key := mustMarshalDashboardCacheKey(dashboardEntityTrendCacheKey{
+		StartTime:   startTime.UTC().Format(time.RFC3339),
+		EndTime:     endTime.UTC().Format(time.RFC3339),
+		Granularity: granularity,
+		Limit:       limit,
+	})
+	entry, hit, err := dashboardUsersTrendCache.GetOrLoad(key, func() (any, error) {
+		return h.dashboardService.GetUserUsageTrend(ctx, startTime, endTime, granularity, limit)
+	})
+	if err != nil {
+		return nil, hit, err
+	}
+	trend, err := snapshotPayloadAs[[]usagestats.UserUsageTrendPoint](entry.Payload)
+	return trend, hit, err
+}

backend/internal/handler/admin/dashboard_snapshot_v2_handler.go

@@ -1,7 +1,9 @@
 package admin
 
 import (
+	"context"
 	"encoding/json"
+	"errors"
 	"net/http"
 	"strconv"
 	"strings"
@@ -111,20 +113,45 @@ func (h *DashboardHandler) GetSnapshotV2(c *gin.Context) {
 	})
 	cacheKey := string(keyRaw)
 
-	if cached, ok := dashboardSnapshotV2Cache.Get(cacheKey); ok {
-		if cached.ETag != "" {
-			c.Header("ETag", cached.ETag)
-			c.Header("Vary", "If-None-Match")
-			if ifNoneMatchMatched(c.GetHeader("If-None-Match"), cached.ETag) {
-				c.Status(http.StatusNotModified)
-				return
-			}
-		}
-		c.Header("X-Snapshot-Cache", "hit")
-		response.Success(c, cached.Payload)
+	cached, hit, err := dashboardSnapshotV2Cache.GetOrLoad(cacheKey, func() (any, error) {
+		return h.buildSnapshotV2Response(
+			c.Request.Context(),
+			startTime,
+			endTime,
+			granularity,
+			filters,
+			includeStats,
+			includeTrend,
+			includeModels,
+			includeGroups,
+			includeUsersTrend,
+			usersTrendLimit,
+		)
+	})
+	if err != nil {
+		response.Error(c, 500, err.Error())
 		return
 	}
+	if cached.ETag != "" {
+		c.Header("ETag", cached.ETag)
+		c.Header("Vary", "If-None-Match")
+		if ifNoneMatchMatched(c.GetHeader("If-None-Match"), cached.ETag) {
+			c.Status(http.StatusNotModified)
+			return
+		}
+	}
+	c.Header("X-Snapshot-Cache", cacheStatusValue(hit))
+	response.Success(c, cached.Payload)
+}
 
+func (h *DashboardHandler) buildSnapshotV2Response(
+	ctx context.Context,
+	startTime, endTime time.Time,
+	granularity string,
+	filters *dashboardSnapshotV2Filters,
+	includeStats, includeTrend, includeModels, includeGroups, includeUsersTrend bool,
+	usersTrendLimit int,
+) (*dashboardSnapshotV2Response, error) {
 	resp := &dashboardSnapshotV2Response{
 		GeneratedAt: time.Now().UTC().Format(time.RFC3339),
 		StartDate:   startTime.Format("2006-01-02"),
@@ -133,10 +160,9 @@ func (h *DashboardHandler) GetSnapshotV2(c *gin.Context) {
 	}
 
 	if includeStats {
-		stats, err := h.dashboardService.GetDashboardStats(c.Request.Context())
+		stats, err := h.dashboardService.GetDashboardStats(ctx)
 		if err != nil {
-			response.Error(c, 500, "Failed to get dashboard statistics")
-			return
+			return nil, errors.New("failed to get dashboard statistics")
 		}
 		resp.Stats = &dashboardSnapshotV2Stats{
 			DashboardStats: *stats,
@@ -145,8 +171,8 @@ func (h *DashboardHandler) GetSnapshotV2(c *gin.Context) {
 	}
 
 	if includeTrend {
-		trend, err := h.dashboardService.GetUsageTrendWithFilters(
-			c.Request.Context(),
+		trend, _, err := h.getUsageTrendCached(
+			ctx,
 			startTime,
 			endTime,
 			granularity,
@@ -160,35 +186,34 @@ func (h *DashboardHandler) GetSnapshotV2(c *gin.Context) {
 			filters.BillingType,
 		)
 		if err != nil {
-			response.Error(c, 500, "Failed to get usage trend")
-			return
+			return nil, errors.New("failed to get usage trend")
 		}
 		resp.Trend = trend
 	}
 
 	if includeModels {
-		models, err := h.dashboardService.GetModelStatsWithFilters(
-			c.Request.Context(),
+		models, _, err := h.getModelStatsCached(
+			ctx,
 			startTime,
 			endTime,
 			filters.UserID,
 			filters.APIKeyID,
 			filters.AccountID,
 			filters.GroupID,
+			usagestats.ModelSourceRequested,
 			filters.RequestType,
 			filters.Stream,
 			filters.BillingType,
 		)
 		if err != nil {
-			response.Error(c, 500, "Failed to get model statistics")
-			return
+			return nil, errors.New("failed to get model statistics")
 		}
 		resp.Models = models
 	}
 
 	if includeGroups {
-		groups, err := h.dashboardService.GetGroupStatsWithFilters(
-			c.Request.Context(),
+		groups, _, err := h.getGroupStatsCached(
+			ctx,
 			startTime,
 			endTime,
 			filters.UserID,
@@ -200,34 +225,20 @@ func (h *DashboardHandler) GetSnapshotV2(c *gin.Context) {
 			filters.BillingType,
 		)
 		if err != nil {
-			response.Error(c, 500, "Failed to get group statistics")
-			return
+			return nil, errors.New("failed to get group statistics")
 		}
 		resp.Groups = groups
 	}
 
 	if includeUsersTrend {
-		usersTrend, err := h.dashboardService.GetUserUsageTrend(
-			c.Request.Context(),
-			startTime,
-			endTime,
-			granularity,
-			usersTrendLimit,
-		)
+		usersTrend, _, err := h.getUserUsageTrendCached(ctx, startTime, endTime, granularity, usersTrendLimit)
 		if err != nil {
-			response.Error(c, 500, "Failed to get user usage trend")
-			return
+			return nil, errors.New("failed to get user usage trend")
 		}
 		resp.UsersTrend = usersTrend
 	}
 
-	cached := dashboardSnapshotV2Cache.Set(cacheKey, resp)
-	if cached.ETag != "" {
-		c.Header("ETag", cached.ETag)
-		c.Header("Vary", "If-None-Match")
-	}
-	c.Header("X-Snapshot-Cache", "miss")
-	response.Success(c, resp)
+	return resp, nil
 }
 
 func parseDashboardSnapshotV2Filters(c *gin.Context) (*dashboardSnapshotV2Filters, error) {

backend/internal/handler/admin/group_handler.go

@@ -1,11 +1,15 @@
 package admin
 
 import (
+	"bytes"
+	"encoding/json"
+	"fmt"
 	"strconv"
 	"strings"
 
 	"github.com/Wei-Shaw/sub2api/internal/handler/dto"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/response"
+	"github.com/Wei-Shaw/sub2api/internal/pkg/timezone"
 	"github.com/Wei-Shaw/sub2api/internal/service"
 
 	"github.com/gin-gonic/gin"
@@ -13,27 +17,80 @@ import (
 
 // GroupHandler handles admin group management
 type GroupHandler struct {
-	adminService service.AdminService
+	adminService         service.AdminService
+	dashboardService     *service.DashboardService
+	groupCapacityService *service.GroupCapacityService
+}
+
+type optionalLimitField struct {
+	set   bool
+	value *float64
+}
+
+func (f *optionalLimitField) UnmarshalJSON(data []byte) error {
+	f.set = true
+
+	trimmed := bytes.TrimSpace(data)
+	if bytes.Equal(trimmed, []byte("null")) {
+		f.value = nil
+		return nil
+	}
+
+	var number float64
+	if err := json.Unmarshal(trimmed, &number); err == nil {
+		f.value = &number
+		return nil
+	}
+
+	var text string
+	if err := json.Unmarshal(trimmed, &text); err == nil {
+		text = strings.TrimSpace(text)
+		if text == "" {
+			f.value = nil
+			return nil
+		}
+		number, err = strconv.ParseFloat(text, 64)
+		if err != nil {
+			return fmt.Errorf("invalid numeric limit value %q: %w", text, err)
+		}
+		f.value = &number
+		return nil
+	}
+
+	return fmt.Errorf("invalid limit value: %s", string(trimmed))
+}
+
+func (f optionalLimitField) ToServiceInput() *float64 {
+	if !f.set {
+		return nil
+	}
+	if f.value != nil {
+		return f.value
+	}
+	zero := 0.0
+	return &zero
 }
 
 // NewGroupHandler creates a new admin group handler
-func NewGroupHandler(adminService service.AdminService) *GroupHandler {
+func NewGroupHandler(adminService service.AdminService, dashboardService *service.DashboardService, groupCapacityService *service.GroupCapacityService) *GroupHandler {
 	return &GroupHandler{
-		adminService: adminService,
+		adminService:         adminService,
+		dashboardService:     dashboardService,
+		groupCapacityService: groupCapacityService,
 	}
 }
 
 // CreateGroupRequest represents create group request
 type CreateGroupRequest struct {
-	Name             string   `json:"name" binding:"required"`
-	Description      string   `json:"description"`
-	Platform         string   `json:"platform" binding:"omitempty,oneof=anthropic openai gemini antigravity sora"`
-	RateMultiplier   float64  `json:"rate_multiplier"`
-	IsExclusive      bool     `json:"is_exclusive"`
-	SubscriptionType string   `json:"subscription_type" binding:"omitempty,oneof=standard subscription"`
-	DailyLimitUSD    *float64 `json:"daily_limit_usd"`
-	WeeklyLimitUSD   *float64 `json:"weekly_limit_usd"`
-	MonthlyLimitUSD  *float64 `json:"monthly_limit_usd"`
+	Name             string             `json:"name" binding:"required"`
+	Description      string             `json:"description"`
+	Platform         string             `json:"platform" binding:"omitempty,oneof=anthropic openai gemini antigravity sora"`
+	RateMultiplier   float64            `json:"rate_multiplier"`
+	IsExclusive      bool               `json:"is_exclusive"`
+	SubscriptionType string             `json:"subscription_type" binding:"omitempty,oneof=standard subscription"`
+	DailyLimitUSD    optionalLimitField `json:"daily_limit_usd"`
+	WeeklyLimitUSD   optionalLimitField `json:"weekly_limit_usd"`
+	MonthlyLimitUSD  optionalLimitField `json:"monthly_limit_usd"`
 	// 图片生成计费配置（antigravity 和 gemini 平台使用，负数表示清除配置）
 	ImagePrice1K                    *float64 `json:"image_price_1k"`
 	ImagePrice2K                    *float64 `json:"image_price_2k"`
@@ -62,16 +119,16 @@ type CreateGroupRequest struct {
 
 // UpdateGroupRequest represents update group request
 type UpdateGroupRequest struct {
-	Name             string   `json:"name"`
-	Description      string   `json:"description"`
-	Platform         string   `json:"platform" binding:"omitempty,oneof=anthropic openai gemini antigravity sora"`
-	RateMultiplier   *float64 `json:"rate_multiplier"`
-	IsExclusive      *bool    `json:"is_exclusive"`
-	Status           string   `json:"status" binding:"omitempty,oneof=active inactive"`
-	SubscriptionType string   `json:"subscription_type" binding:"omitempty,oneof=standard subscription"`
-	DailyLimitUSD    *float64 `json:"daily_limit_usd"`
-	WeeklyLimitUSD   *float64 `json:"weekly_limit_usd"`
-	MonthlyLimitUSD  *float64 `json:"monthly_limit_usd"`
+	Name             string             `json:"name"`
+	Description      string             `json:"description"`
+	Platform         string             `json:"platform" binding:"omitempty,oneof=anthropic openai gemini antigravity sora"`
+	RateMultiplier   *float64           `json:"rate_multiplier"`
+	IsExclusive      *bool              `json:"is_exclusive"`
+	Status           string             `json:"status" binding:"omitempty,oneof=active inactive"`
+	SubscriptionType string             `json:"subscription_type" binding:"omitempty,oneof=standard subscription"`
+	DailyLimitUSD    optionalLimitField `json:"daily_limit_usd"`
+	WeeklyLimitUSD   optionalLimitField `json:"weekly_limit_usd"`
+	MonthlyLimitUSD  optionalLimitField `json:"monthly_limit_usd"`
 	// 图片生成计费配置（antigravity 和 gemini 平台使用，负数表示清除配置）
 	ImagePrice1K                    *float64 `json:"image_price_1k"`
 	ImagePrice2K                    *float64 `json:"image_price_2k"`
@@ -191,9 +248,9 @@ func (h *GroupHandler) Create(c *gin.Context) {
 		RateMultiplier:                  req.RateMultiplier,
 		IsExclusive:                     req.IsExclusive,
 		SubscriptionType:                req.SubscriptionType,
-		DailyLimitUSD:                   req.DailyLimitUSD,
-		WeeklyLimitUSD:                  req.WeeklyLimitUSD,
-		MonthlyLimitUSD:                 req.MonthlyLimitUSD,
+		DailyLimitUSD:                   req.DailyLimitUSD.ToServiceInput(),
+		WeeklyLimitUSD:                  req.WeeklyLimitUSD.ToServiceInput(),
+		MonthlyLimitUSD:                 req.MonthlyLimitUSD.ToServiceInput(),
 		ImagePrice1K:                    req.ImagePrice1K,
 		ImagePrice2K:                    req.ImagePrice2K,
 		ImagePrice4K:                    req.ImagePrice4K,
@@ -244,9 +301,9 @@ func (h *GroupHandler) Update(c *gin.Context) {
 		IsExclusive:                     req.IsExclusive,
 		Status:                          req.Status,
 		SubscriptionType:                req.SubscriptionType,
-		DailyLimitUSD:                   req.DailyLimitUSD,
-		WeeklyLimitUSD:                  req.WeeklyLimitUSD,
-		MonthlyLimitUSD:                 req.MonthlyLimitUSD,
+		DailyLimitUSD:                   req.DailyLimitUSD.ToServiceInput(),
+		WeeklyLimitUSD:                  req.WeeklyLimitUSD.ToServiceInput(),
+		MonthlyLimitUSD:                 req.MonthlyLimitUSD.ToServiceInput(),
 		ImagePrice1K:                    req.ImagePrice1K,
 		ImagePrice2K:                    req.ImagePrice2K,
 		ImagePrice4K:                    req.ImagePrice4K,
@@ -311,6 +368,33 @@ func (h *GroupHandler) GetStats(c *gin.Context) {
 	_ = groupID // TODO: implement actual stats
 }
 
+// GetUsageSummary returns today's and cumulative cost for all groups.
+// GET /api/v1/admin/groups/usage-summary?timezone=Asia/Shanghai
+func (h *GroupHandler) GetUsageSummary(c *gin.Context) {
+	userTZ := c.Query("timezone")
+	now := timezone.NowInUserLocation(userTZ)
+	todayStart := timezone.StartOfDayInUserLocation(now, userTZ)
+
+	results, err := h.dashboardService.GetGroupUsageSummary(c.Request.Context(), todayStart)
+	if err != nil {
+		response.Error(c, 500, "Failed to get group usage summary")
+		return
+	}
+
+	response.Success(c, results)
+}
+
+// GetCapacitySummary returns aggregated capacity (concurrency/sessions/RPM) for all active groups.
+// GET /api/v1/admin/groups/capacity-summary
+func (h *GroupHandler) GetCapacitySummary(c *gin.Context) {
+	results, err := h.groupCapacityService.GetAllGroupCapacity(c.Request.Context())
+	if err != nil {
+		response.Error(c, 500, "Failed to get group capacity summary")
+		return
+	}
+	response.Success(c, results)
+}
+
 // GetGroupAPIKeys handles getting API keys in a group
 // GET /api/v1/admin/groups/:id/api-keys
 func (h *GroupHandler) GetGroupAPIKeys(c *gin.Context) {
@@ -335,6 +419,72 @@ func (h *GroupHandler) GetGroupAPIKeys(c *gin.Context) {
 	response.Paginated(c, outKeys, total, page, pageSize)
 }
 
+// GetGroupRateMultipliers handles getting rate multipliers for users in a group
+// GET /api/v1/admin/groups/:id/rate-multipliers
+func (h *GroupHandler) GetGroupRateMultipliers(c *gin.Context) {
+	groupID, err := strconv.ParseInt(c.Param("id"), 10, 64)
+	if err != nil {
+		response.BadRequest(c, "Invalid group ID")
+		return
+	}
+
+	entries, err := h.adminService.GetGroupRateMultipliers(c.Request.Context(), groupID)
+	if err != nil {
+		response.ErrorFrom(c, err)
+		return
+	}
+
+	if entries == nil {
+		entries = []service.UserGroupRateEntry{}
+	}
+	response.Success(c, entries)
+}
+
+// ClearGroupRateMultipliers handles clearing all rate multipliers for a group
+// DELETE /api/v1/admin/groups/:id/rate-multipliers
+func (h *GroupHandler) ClearGroupRateMultipliers(c *gin.Context) {
+	groupID, err := strconv.ParseInt(c.Param("id"), 10, 64)
+	if err != nil {
+		response.BadRequest(c, "Invalid group ID")
+		return
+	}
+
+	if err := h.adminService.ClearGroupRateMultipliers(c.Request.Context(), groupID); err != nil {
+		response.ErrorFrom(c, err)
+		return
+	}
+
+	response.Success(c, gin.H{"message": "Rate multipliers cleared successfully"})
+}
+
+// BatchSetGroupRateMultipliersRequest represents batch set rate multipliers request
+type BatchSetGroupRateMultipliersRequest struct {
+	Entries []service.GroupRateMultiplierInput `json:"entries" binding:"required"`
+}
+
+// BatchSetGroupRateMultipliers handles batch setting rate multipliers for a group
+// PUT /api/v1/admin/groups/:id/rate-multipliers
+func (h *GroupHandler) BatchSetGroupRateMultipliers(c *gin.Context) {
+	groupID, err := strconv.ParseInt(c.Param("id"), 10, 64)
+	if err != nil {
+		response.BadRequest(c, "Invalid group ID")
+		return
+	}
+
+	var req BatchSetGroupRateMultipliersRequest
+	if err := c.ShouldBindJSON(&req); err != nil {
+		response.BadRequest(c, "Invalid request: "+err.Error())
+		return
+	}
+
+	if err := h.adminService.BatchSetGroupRateMultipliers(c.Request.Context(), groupID, req.Entries); err != nil {
+		response.ErrorFrom(c, err)
+		return
+	}
+
+	response.Success(c, gin.H{"message": "Rate multipliers updated successfully"})
+}
+
 // UpdateSortOrderRequest represents the request to update group sort orders
 type UpdateSortOrderRequest struct {
 	Updates []struct {

backend/internal/handler/admin/openai_oauth_handler.go

@@ -289,6 +289,7 @@ func (h *OpenAIOAuthHandler) CreateAccountFromOAuth(c *gin.Context) {
 		Platform:    platform,
 		Type:        "oauth",
 		Credentials: credentials,
+		Extra:       nil,
 		ProxyID:     req.ProxyID,
 		Concurrency: req.Concurrency,
 		Priority:    req.Priority,

backend/internal/handler/admin/ops_alerts_handler.go

@@ -23,6 +23,13 @@ var validOpsAlertMetricTypes = []string{
 	"cpu_usage_percent",
 	"memory_usage_percent",
 	"concurrency_queue_depth",
+	"group_available_accounts",
+	"group_available_ratio",
+	"group_rate_limit_ratio",
+	"account_rate_limited_count",
+	"account_error_count",
+	"account_error_ratio",
+	"overload_account_count",
 }
 
 var validOpsAlertMetricTypeSet = func() map[string]struct{} {
@@ -82,7 +89,10 @@ func isPercentOrRateMetric(metricType string) bool {
 		"error_rate",
 		"upstream_error_rate",
 		"cpu_usage_percent",
-		"memory_usage_percent":
+		"memory_usage_percent",
+		"group_available_ratio",
+		"group_rate_limit_ratio",
+		"account_error_ratio":
 		return true
 	default:
 		return false

backend/internal/handler/admin/redeem_handler.go

@@ -41,12 +41,15 @@ type GenerateRedeemCodesRequest struct {
 }
 
 // CreateAndRedeemCodeRequest represents creating a fixed code and redeeming it for a target user.
+// Type 为 omitempty 而非 required 是为了向后兼容旧版调用方（不传 type 时默认 balance）。
 type CreateAndRedeemCodeRequest struct {
-	Code   string  `json:"code" binding:"required,min=3,max=128"`
-	Type   string  `json:"type" binding:"required,oneof=balance concurrency subscription invitation"`
-	Value  float64 `json:"value" binding:"required,gt=0"`
-	UserID int64   `json:"user_id" binding:"required,gt=0"`
-	Notes  string  `json:"notes"`
+	Code         string  `json:"code" binding:"required,min=3,max=128"`
+	Type         string  `json:"type" binding:"omitempty,oneof=balance concurrency subscription invitation"` // 不传时默认 balance（向后兼容）
+	Value        float64 `json:"value" binding:"required,gt=0"`
+	UserID       int64   `json:"user_id" binding:"required,gt=0"`
+	GroupID      *int64  `json:"group_id"`                                    // subscription 类型必填
+	ValidityDays int     `json:"validity_days" binding:"omitempty,max=36500"` // subscription 类型必填，>0
+	Notes        string  `json:"notes"`
 }
 
 // List handles listing all redeem codes with pagination
@@ -136,6 +139,22 @@ func (h *RedeemHandler) CreateAndRedeem(c *gin.Context) {
 		return
 	}
 	req.Code = strings.TrimSpace(req.Code)
+	// 向后兼容：旧版调用方（如 Sub2ApiPay）不传 type 字段，默认当作 balance 充值处理。
+	// 请勿删除此默认值逻辑，否则会导致旧版调用方 400 报错。
+	if req.Type == "" {
+		req.Type = "balance"
+	}
+
+	if req.Type == "subscription" {
+		if req.GroupID == nil {
+			response.BadRequest(c, "group_id is required for subscription type")
+			return
+		}
+		if req.ValidityDays <= 0 {
+			response.BadRequest(c, "validity_days must be greater than 0 for subscription type")
+			return
+		}
+	}
 
 	executeAdminIdempotentJSON(c, "admin.redeem_codes.create_and_redeem", req, service.DefaultWriteIdempotencyTTL(), func(ctx context.Context) (any, error) {
 		existing, err := h.redeemService.GetByCode(ctx, req.Code)
@@ -147,11 +166,13 @@ func (h *RedeemHandler) CreateAndRedeem(c *gin.Context) {
 		}
 
 		createErr := h.redeemService.CreateCode(ctx, &service.RedeemCode{
-			Code:   req.Code,
-			Type:   req.Type,
-			Value:  req.Value,
-			Status: service.StatusUnused,
-			Notes:  req.Notes,
+			Code:         req.Code,
+			Type:         req.Type,
+			Value:        req.Value,
+			Status:       service.StatusUnused,
+			Notes:        req.Notes,
+			GroupID:      req.GroupID,
+			ValidityDays: req.ValidityDays,
 		})
 		if createErr != nil {
 			// Unique code race: if code now exists, use idempotent semantics by used_by.

backend/internal/handler/admin/redeem_handler_test.go

@@ -0,0 +1,135 @@
+package admin
+
+import (
+	"bytes"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/Wei-Shaw/sub2api/internal/service"
+	"github.com/gin-gonic/gin"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+// newCreateAndRedeemHandler creates a RedeemHandler with a non-nil (but minimal)
+// RedeemService so that CreateAndRedeem's nil guard passes and we can test the
+// parameter-validation layer that runs before any service call.
+func newCreateAndRedeemHandler() *RedeemHandler {
+	return &RedeemHandler{
+		adminService:  newStubAdminService(),
+		redeemService: &service.RedeemService{}, // non-nil to pass nil guard
+	}
+}
+
+// postCreateAndRedeemValidation calls CreateAndRedeem and returns the response
+// status code. For cases that pass validation and proceed into the service layer,
+// a panic may occur (because RedeemService internals are nil); this is expected
+// and treated as "validation passed" (returns 0 to indicate panic).
+func postCreateAndRedeemValidation(t *testing.T, handler *RedeemHandler, body any) (code int) {
+	t.Helper()
+	gin.SetMode(gin.TestMode)
+	w := httptest.NewRecorder()
+	c, _ := gin.CreateTestContext(w)
+
+	jsonBytes, err := json.Marshal(body)
+	require.NoError(t, err)
+	c.Request, _ = http.NewRequest(http.MethodPost, "/api/v1/admin/redeem-codes/create-and-redeem", bytes.NewReader(jsonBytes))
+	c.Request.Header.Set("Content-Type", "application/json")
+
+	defer func() {
+		if r := recover(); r != nil {
+			// Panic means we passed validation and entered service layer (expected for minimal stub).
+			code = 0
+		}
+	}()
+	handler.CreateAndRedeem(c)
+	return w.Code
+}
+
+func TestCreateAndRedeem_TypeDefaultsToBalance(t *testing.T) {
+	// 不传 type 字段时应默认 balance，不触发 subscription 校验。
+	// 验证通过后进入 service 层会 panic（返回 0），说明默认值生效。
+	h := newCreateAndRedeemHandler()
+	code := postCreateAndRedeemValidation(t, h, map[string]any{
+		"code":    "test-balance-default",
+		"value":   10.0,
+		"user_id": 1,
+	})
+
+	assert.NotEqual(t, http.StatusBadRequest, code,
+		"omitting type should default to balance and pass validation")
+}
+
+func TestCreateAndRedeem_SubscriptionRequiresGroupID(t *testing.T) {
+	h := newCreateAndRedeemHandler()
+	code := postCreateAndRedeemValidation(t, h, map[string]any{
+		"code":          "test-sub-no-group",
+		"type":          "subscription",
+		"value":         29.9,
+		"user_id":       1,
+		"validity_days": 30,
+		// group_id 缺失
+	})
+
+	assert.Equal(t, http.StatusBadRequest, code)
+}
+
+func TestCreateAndRedeem_SubscriptionRequiresPositiveValidityDays(t *testing.T) {
+	groupID := int64(5)
+	h := newCreateAndRedeemHandler()
+
+	cases := []struct {
+		name         string
+		validityDays int
+	}{
+		{"zero", 0},
+		{"negative", -1},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			code := postCreateAndRedeemValidation(t, h, map[string]any{
+				"code":          "test-sub-bad-days-" + tc.name,
+				"type":          "subscription",
+				"value":         29.9,
+				"user_id":       1,
+				"group_id":      groupID,
+				"validity_days": tc.validityDays,
+			})
+
+			assert.Equal(t, http.StatusBadRequest, code)
+		})
+	}
+}
+
+func TestCreateAndRedeem_SubscriptionValidParamsPassValidation(t *testing.T) {
+	groupID := int64(5)
+	h := newCreateAndRedeemHandler()
+	code := postCreateAndRedeemValidation(t, h, map[string]any{
+		"code":          "test-sub-valid",
+		"type":          "subscription",
+		"value":         29.9,
+		"user_id":       1,
+		"group_id":      groupID,
+		"validity_days": 31,
+	})
+
+	assert.NotEqual(t, http.StatusBadRequest, code,
+		"valid subscription params should pass validation")
+}
+
+func TestCreateAndRedeem_BalanceIgnoresSubscriptionFields(t *testing.T) {
+	h := newCreateAndRedeemHandler()
+	// balance 类型不传 group_id 和 validity_days，不应报 400
+	code := postCreateAndRedeemValidation(t, h, map[string]any{
+		"code":    "test-balance-no-extras",
+		"type":    "balance",
+		"value":   50.0,
+		"user_id": 1,
+	})
+
+	assert.NotEqual(t, http.StatusBadRequest, code,
+		"balance type should not require group_id or validity_days")
+}

backend/internal/handler/admin/setting_handler.go

@@ -80,6 +80,7 @@ func (h *SettingHandler) GetSettings(c *gin.Context) {
 		RegistrationEmailSuffixWhitelist:     settings.RegistrationEmailSuffixWhitelist,
 		PromoCodeEnabled:                     settings.PromoCodeEnabled,
 		PasswordResetEnabled:                 settings.PasswordResetEnabled,
+		FrontendURL:                          settings.FrontendURL,
 		InvitationCodeEnabled:                settings.InvitationCodeEnabled,
 		TotpEnabled:                          settings.TotpEnabled,
 		TotpEncryptionKeyConfigured:          h.settingService.IsTotpEncryptionKeyConfigured(),
@@ -125,6 +126,7 @@ func (h *SettingHandler) GetSettings(c *gin.Context) {
 		OpsMetricsIntervalSeconds:            settings.OpsMetricsIntervalSeconds,
 		MinClaudeCodeVersion:                 settings.MinClaudeCodeVersion,
 		AllowUngroupedKeyScheduling:          settings.AllowUngroupedKeyScheduling,
+		BackendModeEnabled:                   settings.BackendModeEnabled,
 	})
 }
 
@@ -136,6 +138,7 @@ type UpdateSettingsRequest struct {
 	RegistrationEmailSuffixWhitelist []string `json:"registration_email_suffix_whitelist"`
 	PromoCodeEnabled                 bool     `json:"promo_code_enabled"`
 	PasswordResetEnabled             bool     `json:"password_reset_enabled"`
+	FrontendURL                      string   `json:"frontend_url"`
 	InvitationCodeEnabled            bool     `json:"invitation_code_enabled"`
 	TotpEnabled                      bool     `json:"totp_enabled"` // TOTP 双因素认证
 
@@ -199,6 +202,9 @@ type UpdateSettingsRequest struct {
 
 	// 分组隔离
 	AllowUngroupedKeyScheduling bool `json:"allow_ungrouped_key_scheduling"`
+
+	// Backend Mode
+	BackendModeEnabled bool `json:"backend_mode_enabled"`
 }
 
 // UpdateSettings 更新系统设置
@@ -322,6 +328,15 @@ func (h *SettingHandler) UpdateSettings(c *gin.Context) {
 		}
 	}
 
+	// Frontend URL 验证
+	req.FrontendURL = strings.TrimSpace(req.FrontendURL)
+	if req.FrontendURL != "" {
+		if err := config.ValidateAbsoluteHTTPURL(req.FrontendURL); err != nil {
+			response.BadRequest(c, "Frontend URL must be an absolute http(s) URL")
+			return
+		}
+	}
+
 	// 自定义菜单项验证
 	const (
 		maxCustomMenuItems    = 20
@@ -433,6 +448,7 @@ func (h *SettingHandler) UpdateSettings(c *gin.Context) {
 		RegistrationEmailSuffixWhitelist: req.RegistrationEmailSuffixWhitelist,
 		PromoCodeEnabled:                 req.PromoCodeEnabled,
 		PasswordResetEnabled:             req.PasswordResetEnabled,
+		FrontendURL:                      req.FrontendURL,
 		InvitationCodeEnabled:            req.InvitationCodeEnabled,
 		TotpEnabled:                      req.TotpEnabled,
 		SMTPHost:                         req.SMTPHost,
@@ -473,6 +489,7 @@ func (h *SettingHandler) UpdateSettings(c *gin.Context) {
 		IdentityPatchPrompt:              req.IdentityPatchPrompt,
 		MinClaudeCodeVersion:             req.MinClaudeCodeVersion,
 		AllowUngroupedKeyScheduling:      req.AllowUngroupedKeyScheduling,
+		BackendModeEnabled:               req.BackendModeEnabled,
 		OpsMonitoringEnabled: func() bool {
 			if req.OpsMonitoringEnabled != nil {
 				return *req.OpsMonitoringEnabled
@@ -526,6 +543,7 @@ func (h *SettingHandler) UpdateSettings(c *gin.Context) {
 		RegistrationEmailSuffixWhitelist:     updatedSettings.RegistrationEmailSuffixWhitelist,
 		PromoCodeEnabled:                     updatedSettings.PromoCodeEnabled,
 		PasswordResetEnabled:                 updatedSettings.PasswordResetEnabled,
+		FrontendURL:                          updatedSettings.FrontendURL,
 		InvitationCodeEnabled:                updatedSettings.InvitationCodeEnabled,
 		TotpEnabled:                          updatedSettings.TotpEnabled,
 		TotpEncryptionKeyConfigured:          h.settingService.IsTotpEncryptionKeyConfigured(),
@@ -571,6 +589,7 @@ func (h *SettingHandler) UpdateSettings(c *gin.Context) {
 		OpsMetricsIntervalSeconds:            updatedSettings.OpsMetricsIntervalSeconds,
 		MinClaudeCodeVersion:                 updatedSettings.MinClaudeCodeVersion,
 		AllowUngroupedKeyScheduling:          updatedSettings.AllowUngroupedKeyScheduling,
+		BackendModeEnabled:                   updatedSettings.BackendModeEnabled,
 	})
 }
 
@@ -608,6 +627,9 @@ func diffSettings(before *service.SystemSettings, after *service.SystemSettings,
 	if before.PasswordResetEnabled != after.PasswordResetEnabled {
 		changed = append(changed, "password_reset_enabled")
 	}
+	if before.FrontendURL != after.FrontendURL {
+		changed = append(changed, "frontend_url")
+	}
 	if before.TotpEnabled != after.TotpEnabled {
 		changed = append(changed, "totp_enabled")
 	}
@@ -725,6 +747,9 @@ func diffSettings(before *service.SystemSettings, after *service.SystemSettings,
 	if before.AllowUngroupedKeyScheduling != after.AllowUngroupedKeyScheduling {
 		changed = append(changed, "allow_ungrouped_key_scheduling")
 	}
+	if before.BackendModeEnabled != after.BackendModeEnabled {
+		changed = append(changed, "backend_mode_enabled")
+	}
 	if before.PurchaseSubscriptionEnabled != after.PurchaseSubscriptionEnabled {
 		changed = append(changed, "purchase_subscription_enabled")
 	}
@@ -952,6 +977,58 @@ func (h *SettingHandler) DeleteAdminAPIKey(c *gin.Context) {
 	response.Success(c, gin.H{"message": "Admin API key deleted"})
 }
 
+// GetOverloadCooldownSettings 获取529过载冷却配置
+// GET /api/v1/admin/settings/overload-cooldown
+func (h *SettingHandler) GetOverloadCooldownSettings(c *gin.Context) {
+	settings, err := h.settingService.GetOverloadCooldownSettings(c.Request.Context())
+	if err != nil {
+		response.ErrorFrom(c, err)
+		return
+	}
+
+	response.Success(c, dto.OverloadCooldownSettings{
+		Enabled:         settings.Enabled,
+		CooldownMinutes: settings.CooldownMinutes,
+	})
+}
+
+// UpdateOverloadCooldownSettingsRequest 更新529过载冷却配置请求
+type UpdateOverloadCooldownSettingsRequest struct {
+	Enabled         bool `json:"enabled"`
+	CooldownMinutes int  `json:"cooldown_minutes"`
+}
+
+// UpdateOverloadCooldownSettings 更新529过载冷却配置
+// PUT /api/v1/admin/settings/overload-cooldown
+func (h *SettingHandler) UpdateOverloadCooldownSettings(c *gin.Context) {
+	var req UpdateOverloadCooldownSettingsRequest
+	if err := c.ShouldBindJSON(&req); err != nil {
+		response.BadRequest(c, "Invalid request: "+err.Error())
+		return
+	}
+
+	settings := &service.OverloadCooldownSettings{
+		Enabled:         req.Enabled,
+		CooldownMinutes: req.CooldownMinutes,
+	}
+
+	if err := h.settingService.SetOverloadCooldownSettings(c.Request.Context(), settings); err != nil {
+		response.BadRequest(c, err.Error())
+		return
+	}
+
+	updatedSettings, err := h.settingService.GetOverloadCooldownSettings(c.Request.Context())
+	if err != nil {
+		response.ErrorFrom(c, err)
+		return
+	}
+
+	response.Success(c, dto.OverloadCooldownSettings{
+		Enabled:         updatedSettings.Enabled,
+		CooldownMinutes: updatedSettings.CooldownMinutes,
+	})
+}
+
 // GetStreamTimeoutSettings 获取流超时处理配置
 // GET /api/v1/admin/settings/stream-timeout
 func (h *SettingHandler) GetStreamTimeoutSettings(c *gin.Context) {

backend/internal/handler/admin/snapshot_cache.go

@@ -7,6 +7,8 @@ import (
 	"strings"
 	"sync"
 	"time"
+
+	"golang.org/x/sync/singleflight"
 )
 
 type snapshotCacheEntry struct {
@@ -19,6 +21,12 @@ type snapshotCache struct {
 	mu    sync.RWMutex
 	ttl   time.Duration
 	items map[string]snapshotCacheEntry
+	sf    singleflight.Group
+}
+
+type snapshotCacheLoadResult struct {
+	Entry snapshotCacheEntry
+	Hit   bool
 }
 
 func newSnapshotCache(ttl time.Duration) *snapshotCache {
@@ -70,6 +78,41 @@ func (c *snapshotCache) Set(key string, payload any) snapshotCacheEntry {
 	return entry
 }
 
+func (c *snapshotCache) GetOrLoad(key string, load func() (any, error)) (snapshotCacheEntry, bool, error) {
+	if load == nil {
+		return snapshotCacheEntry{}, false, nil
+	}
+	if entry, ok := c.Get(key); ok {
+		return entry, true, nil
+	}
+	if c == nil || key == "" {
+		payload, err := load()
+		if err != nil {
+			return snapshotCacheEntry{}, false, err
+		}
+		return c.Set(key, payload), false, nil
+	}
+
+	value, err, _ := c.sf.Do(key, func() (any, error) {
+		if entry, ok := c.Get(key); ok {
+			return snapshotCacheLoadResult{Entry: entry, Hit: true}, nil
+		}
+		payload, err := load()
+		if err != nil {
+			return nil, err
+		}
+		return snapshotCacheLoadResult{Entry: c.Set(key, payload), Hit: false}, nil
+	})
+	if err != nil {
+		return snapshotCacheEntry{}, false, err
+	}
+	result, ok := value.(snapshotCacheLoadResult)
+	if !ok {
+		return snapshotCacheEntry{}, false, nil
+	}
+	return result.Entry, result.Hit, nil
+}
+
 func buildETagFromAny(payload any) string {
 	raw, err := json.Marshal(payload)
 	if err != nil {

backend/internal/handler/admin/snapshot_cache_test.go

@@ -3,6 +3,8 @@
 package admin
 
 import (
+	"sync"
+	"sync/atomic"
 	"testing"
 	"time"
 
@@ -95,6 +97,61 @@ func TestBuildETagFromAny_UnmarshalablePayload(t *testing.T) {
 	require.Empty(t, etag)
 }
 
+func TestSnapshotCache_GetOrLoad_MissThenHit(t *testing.T) {
+	c := newSnapshotCache(5 * time.Second)
+	var loads atomic.Int32
+
+	entry, hit, err := c.GetOrLoad("key1", func() (any, error) {
+		loads.Add(1)
+		return map[string]string{"hello": "world"}, nil
+	})
+	require.NoError(t, err)
+	require.False(t, hit)
+	require.NotEmpty(t, entry.ETag)
+	require.Equal(t, int32(1), loads.Load())
+
+	entry2, hit, err := c.GetOrLoad("key1", func() (any, error) {
+		loads.Add(1)
+		return map[string]string{"unexpected": "value"}, nil
+	})
+	require.NoError(t, err)
+	require.True(t, hit)
+	require.Equal(t, entry.ETag, entry2.ETag)
+	require.Equal(t, int32(1), loads.Load())
+}
+
+func TestSnapshotCache_GetOrLoad_ConcurrentSingleflight(t *testing.T) {
+	c := newSnapshotCache(5 * time.Second)
+	var loads atomic.Int32
+	start := make(chan struct{})
+	const callers = 8
+	errCh := make(chan error, callers)
+
+	var wg sync.WaitGroup
+	wg.Add(callers)
+	for range callers {
+		go func() {
+			defer wg.Done()
+			<-start
+			_, _, err := c.GetOrLoad("shared", func() (any, error) {
+				loads.Add(1)
+				time.Sleep(20 * time.Millisecond)
+				return "value", nil
+			})
+			errCh <- err
+		}()
+	}
+	close(start)
+	wg.Wait()
+	close(errCh)
+
+	for err := range errCh {
+		require.NoError(t, err)
+	}
+
+	require.Equal(t, int32(1), loads.Load())
+}
+
 func TestParseBoolQueryWithDefault(t *testing.T) {
 	tests := []struct {
 		name string

backend/internal/handler/admin/subscription_handler.go

@@ -77,12 +77,13 @@ func (h *SubscriptionHandler) List(c *gin.Context) {
 		}
 	}
 	status := c.Query("status")
+	platform := c.Query("platform")
 
 	// Parse sorting parameters
 	sortBy := c.DefaultQuery("sort_by", "created_at")
 	sortOrder := c.DefaultQuery("sort_order", "desc")
 
-	subscriptions, pagination, err := h.subscriptionService.List(c.Request.Context(), page, pageSize, userID, groupID, status, sortBy, sortOrder)
+	subscriptions, pagination, err := h.subscriptionService.List(c.Request.Context(), page, pageSize, userID, groupID, status, platform, sortBy, sortOrder)
 	if err != nil {
 		response.ErrorFrom(c, err)
 		return
@@ -216,6 +217,38 @@ func (h *SubscriptionHandler) Extend(c *gin.Context) {
 	})
 }
 
+// ResetSubscriptionQuotaRequest represents the reset quota request
+type ResetSubscriptionQuotaRequest struct {
+	Daily   bool `json:"daily"`
+	Weekly  bool `json:"weekly"`
+	Monthly bool `json:"monthly"`
+}
+
+// ResetQuota resets daily, weekly, and/or monthly usage for a subscription.
+// POST /api/v1/admin/subscriptions/:id/reset-quota
+func (h *SubscriptionHandler) ResetQuota(c *gin.Context) {
+	subscriptionID, err := strconv.ParseInt(c.Param("id"), 10, 64)
+	if err != nil {
+		response.BadRequest(c, "Invalid subscription ID")
+		return
+	}
+	var req ResetSubscriptionQuotaRequest
+	if err := c.ShouldBindJSON(&req); err != nil {
+		response.BadRequest(c, "Invalid request: "+err.Error())
+		return
+	}
+	if !req.Daily && !req.Weekly && !req.Monthly {
+		response.BadRequest(c, "At least one of 'daily', 'weekly', or 'monthly' must be true")
+		return
+	}
+	sub, err := h.subscriptionService.AdminResetQuota(c.Request.Context(), subscriptionID, req.Daily, req.Weekly, req.Monthly)
+	if err != nil {
+		response.ErrorFrom(c, err)
+		return
+	}
+	response.Success(c, dto.UserSubscriptionFromServiceAdmin(sub))
+}
+
 // Revoke handles revoking a subscription
 // DELETE /api/v1/admin/subscriptions/:id
 func (h *SubscriptionHandler) Revoke(c *gin.Context) {

backend/internal/handler/admin/usage_handler.go

@@ -159,8 +159,8 @@ func (h *UsageHandler) List(c *gin.Context) {
 			response.BadRequest(c, "Invalid end_date format, use YYYY-MM-DD")
 			return
 		}
-		// Set end time to end of day
-		t = t.Add(24*time.Hour - time.Nanosecond)
+		// Use half-open range [start, end), move to next calendar day start (DST-safe).
+		t = t.AddDate(0, 0, 1)
 		endTime = &t
 	}
 
@@ -285,7 +285,8 @@ func (h *UsageHandler) Stats(c *gin.Context) {
 			response.BadRequest(c, "Invalid end_date format, use YYYY-MM-DD")
 			return
 		}
-		endTime = endTime.Add(24*time.Hour - time.Nanosecond)
+		// 与 SQL 条件 created_at < end 对齐，使用次日 00:00 作为上边界（DST-safe）。
+		endTime = endTime.AddDate(0, 0, 1)
 	} else {
 		period := c.DefaultQuery("period", "today")
 		switch period {

backend/internal/handler/auth_handler.go

@@ -194,6 +194,12 @@ func (h *AuthHandler) Login(c *gin.Context) {
 		return
 	}
 
+	// Backend mode: only admin can login
+	if h.settingSvc.IsBackendModeEnabled(c.Request.Context()) && !user.IsAdmin() {
+		response.Forbidden(c, "Backend mode is active. Only admin login is allowed.")
+		return
+	}
+
 	h.respondWithTokenPair(c, user)
 }
 
@@ -250,16 +256,22 @@ func (h *AuthHandler) Login2FA(c *gin.Context) {
 		return
 	}
 
-	// Delete the login session
-	_ = h.totpService.DeleteLoginSession(c.Request.Context(), req.TempToken)
-
-	// Get the user
+	// Get the user (before session deletion so we can check backend mode)
 	user, err := h.userService.GetByID(c.Request.Context(), session.UserID)
 	if err != nil {
 		response.ErrorFrom(c, err)
 		return
 	}
 
+	// Backend mode: only admin can login (check BEFORE deleting session)
+	if h.settingSvc.IsBackendModeEnabled(c.Request.Context()) && !user.IsAdmin() {
+		response.Forbidden(c, "Backend mode is active. Only admin login is allowed.")
+		return
+	}
+
+	// Delete the login session (only after all checks pass)
+	_ = h.totpService.DeleteLoginSession(c.Request.Context(), req.TempToken)
+
 	h.respondWithTokenPair(c, user)
 }
 
@@ -447,9 +459,9 @@ func (h *AuthHandler) ForgotPassword(c *gin.Context) {
 		return
 	}
 
-	frontendBaseURL := strings.TrimSpace(h.cfg.Server.FrontendURL)
+	frontendBaseURL := strings.TrimSpace(h.settingSvc.GetFrontendURL(c.Request.Context()))
 	if frontendBaseURL == "" {
-		slog.Error("server.frontend_url not configured; cannot build password reset link")
+		slog.Error("frontend_url not configured in settings or config; cannot build password reset link")
 		response.InternalError(c, "Password reset is not configured")
 		return
 	}
@@ -522,16 +534,22 @@ func (h *AuthHandler) RefreshToken(c *gin.Context) {
 		return
 	}
 
-	tokenPair, err := h.authService.RefreshTokenPair(c.Request.Context(), req.RefreshToken)
+	result, err := h.authService.RefreshTokenPair(c.Request.Context(), req.RefreshToken)
 	if err != nil {
 		response.ErrorFrom(c, err)
 		return
 	}
 
+	// Backend mode: block non-admin token refresh
+	if h.settingSvc.IsBackendModeEnabled(c.Request.Context()) && result.UserRole != "admin" {
+		response.Forbidden(c, "Backend mode is active. Only admin login is allowed.")
+		return
+	}
+
 	response.Success(c, RefreshTokenResponse{
-		AccessToken:  tokenPair.AccessToken,
-		RefreshToken: tokenPair.RefreshToken,
-		ExpiresIn:    tokenPair.ExpiresIn,
+		AccessToken:  result.AccessToken,
+		RefreshToken: result.RefreshToken,
+		ExpiresIn:    result.ExpiresIn,
 		TokenType:    "Bearer",
 	})
 }

backend/internal/handler/dto/mappers.go

@@ -135,14 +135,16 @@ func GroupFromServiceAdmin(g *service.Group) *AdminGroup {
 		return nil
 	}
 	out := &AdminGroup{
-		Group:                groupFromServiceBase(g),
-		ModelRouting:         g.ModelRouting,
-		ModelRoutingEnabled:  g.ModelRoutingEnabled,
-		MCPXMLInject:         g.MCPXMLInject,
-		DefaultMappedModel:   g.DefaultMappedModel,
-		SupportedModelScopes: g.SupportedModelScopes,
-		AccountCount:         g.AccountCount,
-		SortOrder:            g.SortOrder,
+		Group:                   groupFromServiceBase(g),
+		ModelRouting:            g.ModelRouting,
+		ModelRoutingEnabled:     g.ModelRoutingEnabled,
+		MCPXMLInject:            g.MCPXMLInject,
+		DefaultMappedModel:      g.DefaultMappedModel,
+		SupportedModelScopes:    g.SupportedModelScopes,
+		AccountCount:            g.AccountCount,
+		ActiveAccountCount:      g.ActiveAccountCount,
+		RateLimitedAccountCount: g.RateLimitedAccountCount,
+		SortOrder:               g.SortOrder,
 	}
 	if len(g.AccountGroups) > 0 {
 		out.AccountGroups = make([]AccountGroup, 0, len(g.AccountGroups))
@@ -264,8 +266,8 @@ func AccountFromServiceShallow(a *service.Account) *Account {
 		}
 	}
 
-	// 提取 API Key 账号配额限制（仅 apikey 类型有效）
-	if a.Type == service.AccountTypeAPIKey {
+	// 提取账号配额限制（apikey / bedrock 类型有效）
+	if a.IsAPIKeyOrBedrock() {
 		if limit := a.GetQuotaLimit(); limit > 0 {
 			out.QuotaLimit = &limit
 			used := a.GetQuotaUsed()
@@ -281,6 +283,31 @@ func AccountFromServiceShallow(a *service.Account) *Account {
 			used := a.GetQuotaWeeklyUsed()
 			out.QuotaWeeklyUsed = &used
 		}
+		// 固定时间重置配置
+		if mode := a.GetQuotaDailyResetMode(); mode == "fixed" {
+			out.QuotaDailyResetMode = &mode
+			hour := a.GetQuotaDailyResetHour()
+			out.QuotaDailyResetHour = &hour
+		}
+		if mode := a.GetQuotaWeeklyResetMode(); mode == "fixed" {
+			out.QuotaWeeklyResetMode = &mode
+			day := a.GetQuotaWeeklyResetDay()
+			out.QuotaWeeklyResetDay = &day
+			hour := a.GetQuotaWeeklyResetHour()
+			out.QuotaWeeklyResetHour = &hour
+		}
+		if a.GetQuotaDailyResetMode() == "fixed" || a.GetQuotaWeeklyResetMode() == "fixed" {
+			tz := a.GetQuotaResetTimezone()
+			out.QuotaResetTimezone = &tz
+		}
+		if a.Extra != nil {
+			if v, ok := a.Extra["quota_daily_reset_at"].(string); ok && v != "" {
+				out.QuotaDailyResetAt = &v
+			}
+			if v, ok := a.Extra["quota_weekly_reset_at"].(string); ok && v != "" {
+				out.QuotaWeeklyResetAt = &v
+			}
+		}
 	}
 
 	return out
@@ -496,8 +523,11 @@ func usageLogFromServiceUser(l *service.UsageLog) UsageLog {
 		AccountID:             l.AccountID,
 		RequestID:             l.RequestID,
 		Model:                 l.Model,
+		UpstreamModel:         l.UpstreamModel,
 		ServiceTier:           l.ServiceTier,
 		ReasoningEffort:       l.ReasoningEffort,
+		InboundEndpoint:       l.InboundEndpoint,
+		UpstreamEndpoint:      l.UpstreamEndpoint,
 		GroupID:               l.GroupID,
 		SubscriptionID:        l.SubscriptionID,
 		InputTokens:           l.InputTokens,

backend/internal/handler/dto/mappers_usage_test.go

@@ -76,10 +76,14 @@ func TestUsageLogFromService_IncludesServiceTierForUserAndAdmin(t *testing.T) {
 	t.Parallel()
 
 	serviceTier := "priority"
+	inboundEndpoint := "/v1/chat/completions"
+	upstreamEndpoint := "/v1/responses"
 	log := &service.UsageLog{
 		RequestID:             "req_3",
 		Model:                 "gpt-5.4",
 		ServiceTier:           &serviceTier,
+		InboundEndpoint:       &inboundEndpoint,
+		UpstreamEndpoint:      &upstreamEndpoint,
 		AccountRateMultiplier: f64Ptr(1.5),
 	}
 
@@ -88,8 +92,16 @@ func TestUsageLogFromService_IncludesServiceTierForUserAndAdmin(t *testing.T) {
 
 	require.NotNil(t, userDTO.ServiceTier)
 	require.Equal(t, serviceTier, *userDTO.ServiceTier)
+	require.NotNil(t, userDTO.InboundEndpoint)
+	require.Equal(t, inboundEndpoint, *userDTO.InboundEndpoint)
+	require.NotNil(t, userDTO.UpstreamEndpoint)
+	require.Equal(t, upstreamEndpoint, *userDTO.UpstreamEndpoint)
 	require.NotNil(t, adminDTO.ServiceTier)
 	require.Equal(t, serviceTier, *adminDTO.ServiceTier)
+	require.NotNil(t, adminDTO.InboundEndpoint)
+	require.Equal(t, inboundEndpoint, *adminDTO.InboundEndpoint)
+	require.NotNil(t, adminDTO.UpstreamEndpoint)
+	require.Equal(t, upstreamEndpoint, *adminDTO.UpstreamEndpoint)
 	require.NotNil(t, adminDTO.AccountRateMultiplier)
 	require.InDelta(t, 1.5, *adminDTO.AccountRateMultiplier, 1e-12)
 }

backend/internal/handler/dto/settings.go

@@ -22,6 +22,7 @@ type SystemSettings struct {
 	RegistrationEmailSuffixWhitelist []string `json:"registration_email_suffix_whitelist"`
 	PromoCodeEnabled                 bool     `json:"promo_code_enabled"`
 	PasswordResetEnabled             bool     `json:"password_reset_enabled"`
+	FrontendURL                      string   `json:"frontend_url"`
 	InvitationCodeEnabled            bool     `json:"invitation_code_enabled"`
 	TotpEnabled                      bool     `json:"totp_enabled"`                   // TOTP 双因素认证
 	TotpEncryptionKeyConfigured      bool     `json:"totp_encryption_key_configured"` // TOTP 加密密钥是否已配置
@@ -81,6 +82,9 @@ type SystemSettings struct {
 
 	// 分组隔离
 	AllowUngroupedKeyScheduling bool `json:"allow_ungrouped_key_scheduling"`
+
+	// Backend Mode
+	BackendModeEnabled bool `json:"backend_mode_enabled"`
 }
 
 type DefaultSubscriptionSetting struct {
@@ -111,6 +115,7 @@ type PublicSettings struct {
 	CustomMenuItems                  []CustomMenuItem `json:"custom_menu_items"`
 	LinuxDoOAuthEnabled              bool             `json:"linuxdo_oauth_enabled"`
 	SoraClientEnabled                bool             `json:"sora_client_enabled"`
+	BackendModeEnabled               bool             `json:"backend_mode_enabled"`
 	Version                          string           `json:"version"`
 }
 
@@ -152,6 +157,12 @@ type ListSoraS3ProfilesResponse struct {
 	Items           []SoraS3Profile `json:"items"`
 }
 
+// OverloadCooldownSettings 529过载冷却配置 DTO
+type OverloadCooldownSettings struct {
+	Enabled         bool `json:"enabled"`
+	CooldownMinutes int  `json:"cooldown_minutes"`
+}
+
 // StreamTimeoutSettings 流超时处理配置 DTO
 type StreamTimeoutSettings struct {
 	Enabled                bool   `json:"enabled"`

backend/internal/handler/dto/types.go

@@ -122,9 +122,11 @@ type AdminGroup struct {
 	DefaultMappedModel string `json:"default_mapped_model"`
 
 	// 支持的模型系列（仅 antigravity 平台使用）
-	SupportedModelScopes []string       `json:"supported_model_scopes"`
-	AccountGroups        []AccountGroup `json:"account_groups,omitempty"`
-	AccountCount         int64          `json:"account_count,omitempty"`
+	SupportedModelScopes    []string       `json:"supported_model_scopes"`
+	AccountGroups           []AccountGroup `json:"account_groups,omitempty"`
+	AccountCount            int64          `json:"account_count,omitempty"`
+	ActiveAccountCount      int64          `json:"active_account_count,omitempty"`
+	RateLimitedAccountCount int64          `json:"rate_limited_account_count,omitempty"`
 
 	// 分组排序
 	SortOrder int `json:"sort_order"`
@@ -203,6 +205,16 @@ type Account struct {
 	QuotaWeeklyLimit *float64 `json:"quota_weekly_limit,omitempty"`
 	QuotaWeeklyUsed  *float64 `json:"quota_weekly_used,omitempty"`
 
+	// 配额固定时间重置配置
+	QuotaDailyResetMode  *string `json:"quota_daily_reset_mode,omitempty"`
+	QuotaDailyResetHour  *int    `json:"quota_daily_reset_hour,omitempty"`
+	QuotaWeeklyResetMode *string `json:"quota_weekly_reset_mode,omitempty"`
+	QuotaWeeklyResetDay  *int    `json:"quota_weekly_reset_day,omitempty"`
+	QuotaWeeklyResetHour *int    `json:"quota_weekly_reset_hour,omitempty"`
+	QuotaResetTimezone   *string `json:"quota_reset_timezone,omitempty"`
+	QuotaDailyResetAt    *string `json:"quota_daily_reset_at,omitempty"`
+	QuotaWeeklyResetAt   *string `json:"quota_weekly_reset_at,omitempty"`
+
 	Proxy         *Proxy         `json:"proxy,omitempty"`
 	AccountGroups []AccountGroup `json:"account_groups,omitempty"`
 
@@ -322,11 +334,18 @@ type UsageLog struct {
 	AccountID int64  `json:"account_id"`
 	RequestID string `json:"request_id"`
 	Model     string `json:"model"`
+	// UpstreamModel is the actual model sent to the upstream provider after mapping.
+	// Omitted when no mapping was applied (requested model was used as-is).
+	UpstreamModel *string `json:"upstream_model,omitempty"`
 	// ServiceTier records the OpenAI service tier used for billing, e.g. "priority" / "flex".
 	ServiceTier *string `json:"service_tier,omitempty"`
-	// ReasoningEffort is the request's reasoning effort level (OpenAI Responses API).
-	// nil means not provided / not applicable.
+	// ReasoningEffort is the request's reasoning effort level.
+	// OpenAI: "low"/"medium"/"high"/"xhigh"; Claude: "low"/"medium"/"high"/"max".
 	ReasoningEffort *string `json:"reasoning_effort,omitempty"`
+	// InboundEndpoint is the client-facing API endpoint path, e.g. /v1/chat/completions.
+	InboundEndpoint *string `json:"inbound_endpoint,omitempty"`
+	// UpstreamEndpoint is the normalized upstream endpoint path, e.g. /v1/responses.
+	UpstreamEndpoint *string `json:"upstream_endpoint,omitempty"`
 
 	GroupID        *int64 `json:"group_id"`
 	SubscriptionID *int64 `json:"subscription_id"`

backend/internal/handler/endpoint.go

@@ -0,0 +1,174 @@
+package handler
+
+import (
+	"strings"
+
+	"github.com/Wei-Shaw/sub2api/internal/service"
+	"github.com/gin-gonic/gin"
+)
+
+// ──────────────────────────────────────────────────────────
+// Canonical inbound / upstream endpoint paths.
+// All normalization and derivation reference this single set
+// of constants — add new paths HERE when a new API surface
+// is introduced.
+// ──────────────────────────────────────────────────────────
+
+const (
+	EndpointMessages        = "/v1/messages"
+	EndpointChatCompletions = "/v1/chat/completions"
+	EndpointResponses       = "/v1/responses"
+	EndpointGeminiModels    = "/v1beta/models"
+)
+
+// gin.Context keys used by the middleware and helpers below.
+const (
+	ctxKeyInboundEndpoint = "_gateway_inbound_endpoint"
+)
+
+// ──────────────────────────────────────────────────────────
+// Normalization functions
+// ──────────────────────────────────────────────────────────
+
+// NormalizeInboundEndpoint maps a raw request path (which may carry
+// prefixes like /antigravity, /openai, /sora) to its canonical form.
+//
+//	"/antigravity/v1/messages"   → "/v1/messages"
+//	"/v1/chat/completions"       → "/v1/chat/completions"
+//	"/openai/v1/responses/foo"   → "/v1/responses"
+//	"/v1beta/models/gemini:gen"  → "/v1beta/models"
+func NormalizeInboundEndpoint(path string) string {
+	path = strings.TrimSpace(path)
+	switch {
+	case strings.Contains(path, EndpointChatCompletions):
+		return EndpointChatCompletions
+	case strings.Contains(path, EndpointMessages):
+		return EndpointMessages
+	case strings.Contains(path, EndpointResponses):
+		return EndpointResponses
+	case strings.Contains(path, EndpointGeminiModels):
+		return EndpointGeminiModels
+	default:
+		return path
+	}
+}
+
+// DeriveUpstreamEndpoint determines the upstream endpoint from the
+// account platform and the normalized inbound endpoint.
+//
+// Platform-specific rules:
+//   - OpenAI always forwards to /v1/responses (with optional subpath
+//     such as /v1/responses/compact preserved from the raw URL).
+//   - Anthropic  → /v1/messages
+//   - Gemini     → /v1beta/models
+//   - Sora       → /v1/chat/completions
+//   - Antigravity routes may target either Claude or Gemini, so the
+//     inbound endpoint is used to distinguish.
+func DeriveUpstreamEndpoint(inbound, rawRequestPath, platform string) string {
+	inbound = strings.TrimSpace(inbound)
+
+	switch platform {
+	case service.PlatformOpenAI:
+		// OpenAI forwards everything to the Responses API.
+		// Preserve subresource suffix (e.g. /v1/responses/compact).
+		if suffix := responsesSubpathSuffix(rawRequestPath); suffix != "" {
+			return EndpointResponses + suffix
+		}
+		return EndpointResponses
+
+	case service.PlatformAnthropic:
+		return EndpointMessages
+
+	case service.PlatformGemini:
+		return EndpointGeminiModels
+
+	case service.PlatformSora:
+		return EndpointChatCompletions
+
+	case service.PlatformAntigravity:
+		// Antigravity accounts serve both Claude and Gemini.
+		if inbound == EndpointGeminiModels {
+			return EndpointGeminiModels
+		}
+		return EndpointMessages
+	}
+
+	// Unknown platform — fall back to inbound.
+	return inbound
+}
+
+// responsesSubpathSuffix extracts the part after "/responses" in a raw
+// request path, e.g. "/openai/v1/responses/compact" → "/compact".
+// Returns "" when there is no meaningful suffix.
+func responsesSubpathSuffix(rawPath string) string {
+	trimmed := strings.TrimRight(strings.TrimSpace(rawPath), "/")
+	idx := strings.LastIndex(trimmed, "/responses")
+	if idx < 0 {
+		return ""
+	}
+	suffix := trimmed[idx+len("/responses"):]
+	if suffix == "" || suffix == "/" {
+		return ""
+	}
+	if !strings.HasPrefix(suffix, "/") {
+		return ""
+	}
+	return suffix
+}
+
+// ──────────────────────────────────────────────────────────
+// Middleware
+// ──────────────────────────────────────────────────────────
+
+// InboundEndpointMiddleware normalizes the request path and stores the
+// canonical inbound endpoint in gin.Context so that every handler in
+// the chain can read it via GetInboundEndpoint.
+//
+// Apply this middleware to all gateway route groups.
+func InboundEndpointMiddleware() gin.HandlerFunc {
+	return func(c *gin.Context) {
+		path := c.FullPath()
+		if path == "" && c.Request != nil && c.Request.URL != nil {
+			path = c.Request.URL.Path
+		}
+		c.Set(ctxKeyInboundEndpoint, NormalizeInboundEndpoint(path))
+		c.Next()
+	}
+}
+
+// ──────────────────────────────────────────────────────────
+// Context helpers — used by handlers before building
+// RecordUsageInput / RecordUsageLongContextInput.
+// ──────────────────────────────────────────────────────────
+
+// GetInboundEndpoint returns the canonical inbound endpoint stored by
+// InboundEndpointMiddleware. If the middleware did not run (e.g. in
+// tests), it falls back to normalizing c.FullPath() on the fly.
+func GetInboundEndpoint(c *gin.Context) string {
+	if v, ok := c.Get(ctxKeyInboundEndpoint); ok {
+		if s, ok := v.(string); ok && s != "" {
+			return s
+		}
+	}
+	// Fallback: normalize on the fly.
+	path := ""
+	if c != nil {
+		path = c.FullPath()
+		if path == "" && c.Request != nil && c.Request.URL != nil {
+			path = c.Request.URL.Path
+		}
+	}
+	return NormalizeInboundEndpoint(path)
+}
+
+// GetUpstreamEndpoint derives the upstream endpoint from the context
+// and the account platform. Handlers call this after scheduling an
+// account, passing account.Platform.
+func GetUpstreamEndpoint(c *gin.Context, platform string) string {
+	inbound := GetInboundEndpoint(c)
+	rawPath := ""
+	if c != nil && c.Request != nil && c.Request.URL != nil {
+		rawPath = c.Request.URL.Path
+	}
+	return DeriveUpstreamEndpoint(inbound, rawPath, platform)
+}

backend/internal/handler/endpoint_test.go

@@ -0,0 +1,159 @@
+package handler
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/Wei-Shaw/sub2api/internal/service"
+	"github.com/gin-gonic/gin"
+	"github.com/stretchr/testify/require"
+)
+
+func init() { gin.SetMode(gin.TestMode) }
+
+// ──────────────────────────────────────────────────────────
+// NormalizeInboundEndpoint
+// ──────────────────────────────────────────────────────────
+
+func TestNormalizeInboundEndpoint(t *testing.T) {
+	tests := []struct {
+		path string
+		want string
+	}{
+		// Direct canonical paths.
+		{"/v1/messages", EndpointMessages},
+		{"/v1/chat/completions", EndpointChatCompletions},
+		{"/v1/responses", EndpointResponses},
+		{"/v1beta/models", EndpointGeminiModels},
+
+		// Prefixed paths (antigravity, openai, sora).
+		{"/antigravity/v1/messages", EndpointMessages},
+		{"/openai/v1/responses", EndpointResponses},
+		{"/openai/v1/responses/compact", EndpointResponses},
+		{"/sora/v1/chat/completions", EndpointChatCompletions},
+		{"/antigravity/v1beta/models/gemini:generateContent", EndpointGeminiModels},
+
+		// Gin route patterns with wildcards.
+		{"/v1beta/models/*modelAction", EndpointGeminiModels},
+		{"/v1/responses/*subpath", EndpointResponses},
+
+		// Unknown path is returned as-is.
+		{"/v1/embeddings", "/v1/embeddings"},
+		{"", ""},
+		{"  /v1/messages  ", EndpointMessages},
+	}
+	for _, tt := range tests {
+		t.Run(tt.path, func(t *testing.T) {
+			require.Equal(t, tt.want, NormalizeInboundEndpoint(tt.path))
+		})
+	}
+}
+
+// ──────────────────────────────────────────────────────────
+// DeriveUpstreamEndpoint
+// ──────────────────────────────────────────────────────────
+
+func TestDeriveUpstreamEndpoint(t *testing.T) {
+	tests := []struct {
+		name     string
+		inbound  string
+		rawPath  string
+		platform string
+		want     string
+	}{
+		// Anthropic.
+		{"anthropic messages", EndpointMessages, "/v1/messages", service.PlatformAnthropic, EndpointMessages},
+
+		// Gemini.
+		{"gemini models", EndpointGeminiModels, "/v1beta/models/gemini:gen", service.PlatformGemini, EndpointGeminiModels},
+
+		// Sora.
+		{"sora completions", EndpointChatCompletions, "/sora/v1/chat/completions", service.PlatformSora, EndpointChatCompletions},
+
+		// OpenAI — always /v1/responses.
+		{"openai responses root", EndpointResponses, "/v1/responses", service.PlatformOpenAI, EndpointResponses},
+		{"openai responses compact", EndpointResponses, "/openai/v1/responses/compact", service.PlatformOpenAI, "/v1/responses/compact"},
+		{"openai responses nested", EndpointResponses, "/openai/v1/responses/compact/detail", service.PlatformOpenAI, "/v1/responses/compact/detail"},
+		{"openai from messages", EndpointMessages, "/v1/messages", service.PlatformOpenAI, EndpointResponses},
+		{"openai from completions", EndpointChatCompletions, "/v1/chat/completions", service.PlatformOpenAI, EndpointResponses},
+
+		// Antigravity — uses inbound to pick Claude vs Gemini upstream.
+		{"antigravity claude", EndpointMessages, "/antigravity/v1/messages", service.PlatformAntigravity, EndpointMessages},
+		{"antigravity gemini", EndpointGeminiModels, "/antigravity/v1beta/models", service.PlatformAntigravity, EndpointGeminiModels},
+
+		// Unknown platform — passthrough.
+		{"unknown platform", "/v1/embeddings", "/v1/embeddings", "unknown", "/v1/embeddings"},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			require.Equal(t, tt.want, DeriveUpstreamEndpoint(tt.inbound, tt.rawPath, tt.platform))
+		})
+	}
+}
+
+// ──────────────────────────────────────────────────────────
+// responsesSubpathSuffix
+// ──────────────────────────────────────────────────────────
+
+func TestResponsesSubpathSuffix(t *testing.T) {
+	tests := []struct {
+		raw  string
+		want string
+	}{
+		{"/v1/responses", ""},
+		{"/v1/responses/", ""},
+		{"/v1/responses/compact", "/compact"},
+		{"/openai/v1/responses/compact/detail", "/compact/detail"},
+		{"/v1/messages", ""},
+		{"", ""},
+	}
+	for _, tt := range tests {
+		t.Run(tt.raw, func(t *testing.T) {
+			require.Equal(t, tt.want, responsesSubpathSuffix(tt.raw))
+		})
+	}
+}
+
+// ──────────────────────────────────────────────────────────
+// InboundEndpointMiddleware + context helpers
+// ──────────────────────────────────────────────────────────
+
+func TestInboundEndpointMiddleware(t *testing.T) {
+	router := gin.New()
+	router.Use(InboundEndpointMiddleware())
+
+	var captured string
+	router.POST("/v1/messages", func(c *gin.Context) {
+		captured = GetInboundEndpoint(c)
+		c.Status(http.StatusOK)
+	})
+
+	req := httptest.NewRequest(http.MethodPost, "/v1/messages", nil)
+	rec := httptest.NewRecorder()
+	router.ServeHTTP(rec, req)
+
+	require.Equal(t, EndpointMessages, captured)
+}
+
+func TestGetInboundEndpoint_FallbackWithoutMiddleware(t *testing.T) {
+	rec := httptest.NewRecorder()
+	c, _ := gin.CreateTestContext(rec)
+	c.Request = httptest.NewRequest(http.MethodPost, "/antigravity/v1/messages", nil)
+
+	// Middleware did not run — fallback to normalizing c.Request.URL.Path.
+	got := GetInboundEndpoint(c)
+	require.Equal(t, EndpointMessages, got)
+}
+
+func TestGetUpstreamEndpoint_FullFlow(t *testing.T) {
+	rec := httptest.NewRecorder()
+	c, _ := gin.CreateTestContext(rec)
+	c.Request = httptest.NewRequest(http.MethodPost, "/openai/v1/responses/compact", nil)
+
+	// Simulate middleware.
+	c.Set(ctxKeyInboundEndpoint, NormalizeInboundEndpoint(c.Request.URL.Path))
+
+	got := GetUpstreamEndpoint(c, service.PlatformOpenAI)
+	require.Equal(t, "/v1/responses/compact", got)
+}

backend/internal/handler/gateway_handler.go

@@ -391,6 +391,8 @@ func (h *GatewayHandler) Messages(c *gin.Context) {
 			if fs.SwitchCount > 0 {
 				requestCtx = service.WithAccountSwitchCount(requestCtx, fs.SwitchCount, h.metadataBridgeEnabled())
 			}
+			// 记录 Forward 前已写入字节数，Forward 后若增加则说明 SSE 内容已发，禁止 failover
+			writerSizeBeforeForward := c.Writer.Size()
 			if account.Platform == service.PlatformAntigravity {
 				result, err = h.antigravityGatewayService.ForwardGemini(requestCtx, c, account, reqModel, "generateContent", reqStream, body, hasBoundSession)
 			} else {
@@ -402,6 +404,11 @@ func (h *GatewayHandler) Messages(c *gin.Context) {
 			if err != nil {
 				var failoverErr *service.UpstreamFailoverError
 				if errors.As(err, &failoverErr) {
+					// 流式内容已写入客户端，无法撤销，禁止 failover 以防止流拼接腐化
+					if c.Writer.Size() != writerSizeBeforeForward {
+						h.handleFailoverExhausted(c, failoverErr, service.PlatformGemini, true)
+						return
+					}
 					action := fs.HandleFailoverError(c.Request.Context(), h.gatewayService, account.ID, account.Platform, failoverErr)
 					switch action {
 					case FailoverContinue:
@@ -434,19 +441,29 @@ func (h *GatewayHandler) Messages(c *gin.Context) {
 			// 捕获请求信息（用于异步记录，避免在 goroutine 中访问 gin.Context）
 			userAgent := c.GetHeader("User-Agent")
 			clientIP := ip.GetClientIP(c)
+			requestPayloadHash := service.HashUsageRequestPayload(body)
+			inboundEndpoint := GetInboundEndpoint(c)
+			upstreamEndpoint := GetUpstreamEndpoint(c, account.Platform)
+
+			if result.ReasoningEffort == nil {
+				result.ReasoningEffort = service.NormalizeClaudeOutputEffort(parsedReq.OutputEffort)
+			}
 
 			// 使用量记录通过有界 worker 池提交，避免请求热路径创建无界 goroutine。
 			h.submitUsageRecordTask(func(ctx context.Context) {
 				if err := h.gatewayService.RecordUsage(ctx, &service.RecordUsageInput{
-					Result:            result,
-					APIKey:            apiKey,
-					User:              apiKey.User,
-					Account:           account,
-					Subscription:      subscription,
-					UserAgent:         userAgent,
-					IPAddress:         clientIP,
-					ForceCacheBilling: fs.ForceCacheBilling,
-					APIKeyService:     h.apiKeyService,
+					Result:             result,
+					APIKey:             apiKey,
+					User:               apiKey.User,
+					Account:            account,
+					Subscription:       subscription,
+					InboundEndpoint:    inboundEndpoint,
+					UpstreamEndpoint:   upstreamEndpoint,
+					UserAgent:          userAgent,
+					IPAddress:          clientIP,
+					RequestPayloadHash: requestPayloadHash,
+					ForceCacheBilling:  fs.ForceCacheBilling,
+					APIKeyService:      h.apiKeyService,
 				}); err != nil {
 					logger.L().With(
 						zap.String("component", "handler.gateway.messages"),
@@ -635,6 +652,8 @@ func (h *GatewayHandler) Messages(c *gin.Context) {
 			if fs.SwitchCount > 0 {
 				requestCtx = service.WithAccountSwitchCount(requestCtx, fs.SwitchCount, h.metadataBridgeEnabled())
 			}
+			// 记录 Forward 前已写入字节数，Forward 后若增加则说明 SSE 内容已发，禁止 failover
+			writerSizeBeforeForward := c.Writer.Size()
 			if account.Platform == service.PlatformAntigravity && account.Type != service.AccountTypeAPIKey {
 				result, err = h.antigravityGatewayService.Forward(requestCtx, c, account, body, hasBoundSession)
 			} else {
@@ -704,6 +723,11 @@ func (h *GatewayHandler) Messages(c *gin.Context) {
 				}
 				var failoverErr *service.UpstreamFailoverError
 				if errors.As(err, &failoverErr) {
+					// 流式内容已写入客户端，无法撤销，禁止 failover 以防止流拼接腐化
+					if c.Writer.Size() != writerSizeBeforeForward {
+						h.handleFailoverExhausted(c, failoverErr, account.Platform, true)
+						return
+					}
 					action := fs.HandleFailoverError(c.Request.Context(), h.gatewayService, account.ID, account.Platform, failoverErr)
 					switch action {
 					case FailoverContinue:
@@ -736,19 +760,29 @@ func (h *GatewayHandler) Messages(c *gin.Context) {
 			// 捕获请求信息（用于异步记录，避免在 goroutine 中访问 gin.Context）
 			userAgent := c.GetHeader("User-Agent")
 			clientIP := ip.GetClientIP(c)
+			requestPayloadHash := service.HashUsageRequestPayload(body)
+			inboundEndpoint := GetInboundEndpoint(c)
+			upstreamEndpoint := GetUpstreamEndpoint(c, account.Platform)
+
+			if result.ReasoningEffort == nil {
+				result.ReasoningEffort = service.NormalizeClaudeOutputEffort(parsedReq.OutputEffort)
+			}
 
 			// 使用量记录通过有界 worker 池提交，避免请求热路径创建无界 goroutine。
 			h.submitUsageRecordTask(func(ctx context.Context) {
 				if err := h.gatewayService.RecordUsage(ctx, &service.RecordUsageInput{
-					Result:            result,
-					APIKey:            currentAPIKey,
-					User:              currentAPIKey.User,
-					Account:           account,
-					Subscription:      currentSubscription,
-					UserAgent:         userAgent,
-					IPAddress:         clientIP,
-					ForceCacheBilling: fs.ForceCacheBilling,
-					APIKeyService:     h.apiKeyService,
+					Result:             result,
+					APIKey:             currentAPIKey,
+					User:               currentAPIKey.User,
+					Account:            account,
+					Subscription:       currentSubscription,
+					InboundEndpoint:    inboundEndpoint,
+					UpstreamEndpoint:   upstreamEndpoint,
+					UserAgent:          userAgent,
+					IPAddress:          clientIP,
+					RequestPayloadHash: requestPayloadHash,
+					ForceCacheBilling:  fs.ForceCacheBilling,
+					APIKeyService:      h.apiKeyService,
 				}); err != nil {
 					logger.L().With(
 						zap.String("component", "handler.gateway.messages"),
@@ -909,7 +943,7 @@ func (h *GatewayHandler) parseUsageDateRange(c *gin.Context) (time.Time, time.Ti
 	}
 	if s := c.Query("end_date"); s != "" {
 		if t, err := timezone.ParseInLocation("2006-01-02", s); err == nil {
-			endTime = t.Add(24*time.Hour - time.Second) // end of day
+			endTime = t.AddDate(0, 0, 1) // half-open range upper bound
 		}
 	}
 	return startTime, endTime
@@ -1185,6 +1219,10 @@ func (h *GatewayHandler) handleFailoverExhausted(c *gin.Context, failoverErr *se
 		}
 	}
 
+	// 记录原始上游状态码，以便 ops 错误日志捕获真实的上游错误
+	upstreamMsg := service.ExtractUpstreamErrorMessage(responseBody)
+	service.SetOpsUpstreamError(c, statusCode, upstreamMsg, "")
+
 	// 使用默认的错误映射
 	status, errType, errMsg := h.mapUpstreamError(statusCode)
 	h.handleStreamingAwareError(c, status, errType, errMsg, streamStarted)
@@ -1193,6 +1231,7 @@ func (h *GatewayHandler) handleFailoverExhausted(c *gin.Context, failoverErr *se
 // handleFailoverExhaustedSimple 简化版本，用于没有响应体的情况
 func (h *GatewayHandler) handleFailoverExhaustedSimple(c *gin.Context, statusCode int, streamStarted bool) {
 	status, errType, errMsg := h.mapUpstreamError(statusCode)
+	service.SetOpsUpstreamError(c, statusCode, errMsg, "")
 	h.handleStreamingAwareError(c, status, errType, errMsg, streamStarted)
 }
 

backend/internal/handler/gateway_handler_stream_failover_test.go

@@ -0,0 +1,122 @@
+package handler
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"github.com/Wei-Shaw/sub2api/internal/service"
+	"github.com/gin-gonic/gin"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+// partialMessageStartSSE 模拟 handleStreamingResponse 已写入的首批 SSE 事件。
+const partialMessageStartSSE = "event: message_start\ndata: {\"type\":\"message_start\",\"message\":{\"id\":\"msg_01\",\"type\":\"message\",\"role\":\"assistant\",\"content\":[],\"model\":\"claude-sonnet-4-5\",\"stop_reason\":null,\"stop_sequence\":null,\"usage\":{\"input_tokens\":10,\"output_tokens\":1}}}\n\n" +
+	"event: content_block_start\ndata: {\"type\":\"content_block_start\",\"index\":0,\"content_block\":{\"type\":\"text\",\"text\":\"\"}}\n\n"
+
+// TestStreamWrittenGuard_MessagesPath_AbortFailoverOnSSEContentWritten 验证：
+// 当 Forward 在返回 UpstreamFailoverError 前已向客户端写入 SSE 内容时，
+// 故障转移保护逻辑必须终止循环并发送 SSE 错误事件，而不是进行下一次 Forward。
+// 具体验证：
+//  1. c.Writer.Size() 检测条件正确触发（字节数已增加）
+//  2. handleFailoverExhausted 以 streamStarted=true 调用后，响应体以 SSE 错误事件结尾
+//  3. 响应体中只出现一个 message_start，不存在第二个（防止流拼接腐化）
+func TestStreamWrittenGuard_MessagesPath_AbortFailoverOnSSEContentWritten(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+	w := httptest.NewRecorder()
+	c, _ := gin.CreateTestContext(w)
+	c.Request = httptest.NewRequest(http.MethodPost, "/v1/messages", nil)
+
+	// 步骤 1：记录 Forward 前的 writer size（模拟 writerSizeBeforeForward := c.Writer.Size()）
+	sizeBeforeForward := c.Writer.Size()
+	require.Equal(t, -1, sizeBeforeForward, "gin writer 初始 Size 应为 -1（未写入任何字节）")
+
+	// 步骤 2：模拟 Forward 已向客户端写入部分 SSE 内容（message_start + content_block_start）
+	_, err := c.Writer.Write([]byte(partialMessageStartSSE))
+	require.NoError(t, err)
+
+	// 步骤 3：验证守卫条件成立（c.Writer.Size() != sizeBeforeForward）
+	require.NotEqual(t, sizeBeforeForward, c.Writer.Size(),
+		"写入 SSE 内容后 writer size 必须增加，守卫条件应为 true")
+
+	// 步骤 4：模拟 UpstreamFailoverError（上游在流中途返回 403）
+	failoverErr := &service.UpstreamFailoverError{
+		StatusCode:   http.StatusForbidden,
+		ResponseBody: []byte(`{"error":{"type":"permission_error","message":"forbidden"}}`),
+	}
+
+	// 步骤 5：守卫触发 → 调用 handleFailoverExhausted，streamStarted=true
+	h := &GatewayHandler{}
+	h.handleFailoverExhausted(c, failoverErr, service.PlatformAnthropic, true)
+
+	body := w.Body.String()
+
+	// 断言 A：响应体中包含最初写入的 message_start SSE 事件行
+	require.Contains(t, body, "event: message_start", "响应体应包含已写入的 message_start SSE 事件")
+
+	// 断言 B：响应体以 SSE 错误事件结尾（data: {"type":"error",...}\n\n）
+	require.True(t, strings.HasSuffix(strings.TrimRight(body, "\n"), "}"),
+		"响应体应以 JSON 对象结尾（SSE error event 的 data 字段）")
+	require.Contains(t, body, `"type":"error"`, "响应体末尾必须包含 SSE 错误事件")
+
+	// 断言 C：SSE event 行 "event: message_start" 只出现一次（防止双 message_start 拼接腐化）
+	firstIdx := strings.Index(body, "event: message_start")
+	lastIdx := strings.LastIndex(body, "event: message_start")
+	assert.Equal(t, firstIdx, lastIdx,
+		"响应体中 'event: message_start' 必须只出现一次，不得因 failover 拼接导致两次")
+}
+
+// TestStreamWrittenGuard_GeminiPath_AbortFailoverOnSSEContentWritten 与上述测试相同，
+// 验证 Gemini 路径使用 service.PlatformGemini（而非 account.Platform）时行为一致。
+func TestStreamWrittenGuard_GeminiPath_AbortFailoverOnSSEContentWritten(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+	w := httptest.NewRecorder()
+	c, _ := gin.CreateTestContext(w)
+	c.Request = httptest.NewRequest(http.MethodPost, "/v1beta/models/gemini-2.0-flash:streamGenerateContent", nil)
+
+	sizeBeforeForward := c.Writer.Size()
+
+	_, err := c.Writer.Write([]byte(partialMessageStartSSE))
+	require.NoError(t, err)
+
+	require.NotEqual(t, sizeBeforeForward, c.Writer.Size())
+
+	failoverErr := &service.UpstreamFailoverError{
+		StatusCode: http.StatusForbidden,
+	}
+
+	h := &GatewayHandler{}
+	h.handleFailoverExhausted(c, failoverErr, service.PlatformGemini, true)
+
+	body := w.Body.String()
+
+	require.Contains(t, body, "event: message_start")
+	require.Contains(t, body, `"type":"error"`)
+
+	firstIdx := strings.Index(body, "event: message_start")
+	lastIdx := strings.LastIndex(body, "event: message_start")
+	assert.Equal(t, firstIdx, lastIdx, "Gemini 路径不得出现双 message_start")
+}
+
+// TestStreamWrittenGuard_NoByteWritten_GuardNotTriggered 验证反向场景：
+// 当 Forward 返回 UpstreamFailoverError 时若未向客户端写入任何 SSE 内容，
+// 守卫条件（c.Writer.Size() != sizeBeforeForward）为 false，不应中止 failover。
+func TestStreamWrittenGuard_NoByteWritten_GuardNotTriggered(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+	w := httptest.NewRecorder()
+	c, _ := gin.CreateTestContext(w)
+	c.Request = httptest.NewRequest(http.MethodPost, "/v1/messages", nil)
+
+	// 模拟 writerSizeBeforeForward：初始为 -1
+	sizeBeforeForward := c.Writer.Size()
+
+	// Forward 未写入任何字节直接返回错误（例如 401 发生在连接建立前）
+	// c.Writer.Size() 仍为 -1
+
+	// 守卫条件：sizeBeforeForward == c.Writer.Size() → 不触发
+	guardTriggered := c.Writer.Size() != sizeBeforeForward
+	require.False(t, guardTriggered,
+		"未写入任何字节时，守卫条件必须为 false，应允许正常 failover 继续")
+}

backend/internal/handler/gateway_handler_warmup_intercept_unit_test.go

@@ -76,7 +76,7 @@ func (f *fakeGroupRepo) ListActiveByPlatform(context.Context, string) ([]service
 	return nil, nil
 }
 func (f *fakeGroupRepo) ExistsByName(context.Context, string) (bool, error)    { return false, nil }
-func (f *fakeGroupRepo) GetAccountCount(context.Context, int64) (int64, error) { return 0, nil }
+func (f *fakeGroupRepo) GetAccountCount(context.Context, int64) (int64, int64, error) { return 0, 0, nil }
 func (f *fakeGroupRepo) DeleteAccountGroupsByGroupID(context.Context, int64) (int64, error) {
 	return 0, nil
 }
@@ -139,6 +139,7 @@ func newTestGatewayHandler(t *testing.T, group *service.Group, accounts []*servi
 		nil, // accountRepo (not used: scheduler snapshot hit)
 		&fakeGroupRepo{group: group},
 		nil, // usageLogRepo
+		nil, // usageBillingRepo
 		nil, // userRepo
 		nil, // userSubRepo
 		nil, // userGroupRateRepo

backend/internal/handler/gateway_helper_hotpath_test.go

@@ -136,7 +136,7 @@ func validClaudeCodeBodyJSON() []byte {
 	return []byte(`{
 		"model":"claude-3-5-sonnet-20241022",
 		"system":[{"text":"You are Claude Code, Anthropic's official CLI for Claude."}],
-		"metadata":{"user_id":"user_aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa_account__session_abc-123"}
+		"metadata":{"user_id":"user_aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa_account__session_aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa"}
 	}`)
 }
 
@@ -190,7 +190,7 @@ func TestSetClaudeCodeClientContext_ReuseParsedRequestAndContextCache(t *testing
 			System: []any{
 				map[string]any{"text": "You are Claude Code, Anthropic's official CLI for Claude."},
 			},
-			MetadataUserID: "user_aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa_account__session_abc-123",
+			MetadataUserID: "user_aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa_account__session_aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa",
 		}
 
 		// body 非法 JSON，如果函数复用 parsedReq 成功则仍应判定为 Claude Code。
@@ -209,7 +209,7 @@ func TestSetClaudeCodeClientContext_ReuseParsedRequestAndContextCache(t *testing
 			"system": []any{
 				map[string]any{"text": "You are Claude Code, Anthropic's official CLI for Claude."},
 			},
-			"metadata": map[string]any{"user_id": "user_aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa_account__session_abc-123"},
+			"metadata": map[string]any{"user_id": "user_aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa_account__session_aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa"},
 		})
 
 		SetClaudeCodeClientContext(c, []byte(`{invalid`), nil)

backend/internal/handler/gemini_v1beta_handler.go

@@ -503,6 +503,9 @@ func (h *GatewayHandler) GeminiV1BetaModels(c *gin.Context) {
 		}
 
 		// 使用量记录通过有界 worker 池提交，避免请求热路径创建无界 goroutine。
+		requestPayloadHash := service.HashUsageRequestPayload(body)
+		inboundEndpoint := GetInboundEndpoint(c)
+		upstreamEndpoint := GetUpstreamEndpoint(c, account.Platform)
 		h.submitUsageRecordTask(func(ctx context.Context) {
 			if err := h.gatewayService.RecordUsageWithLongContext(ctx, &service.RecordUsageLongContextInput{
 				Result:                result,
@@ -510,8 +513,11 @@ func (h *GatewayHandler) GeminiV1BetaModels(c *gin.Context) {
 				User:                  apiKey.User,
 				Account:               account,
 				Subscription:          subscription,
+				InboundEndpoint:       inboundEndpoint,
+				UpstreamEndpoint:      upstreamEndpoint,
 				UserAgent:             userAgent,
 				IPAddress:             clientIP,
+				RequestPayloadHash:    requestPayloadHash,
 				LongContextThreshold:  200000, // Gemini 200K 阈值
 				LongContextMultiplier: 2.0,    // 超出部分双倍计费
 				ForceCacheBilling:     fs.ForceCacheBilling,
@@ -587,6 +593,10 @@ func (h *GatewayHandler) handleGeminiFailoverExhausted(c *gin.Context, failoverE
 		}
 	}
 
+	// 记录原始上游状态码，以便 ops 错误日志捕获真实的上游错误
+	upstreamMsg := service.ExtractUpstreamErrorMessage(responseBody)
+	service.SetOpsUpstreamError(c, statusCode, upstreamMsg, "")
+
 	// 使用默认的错误映射
 	status, message := mapGeminiUpstreamError(statusCode)
 	googleError(c, status, message)

backend/internal/handler/handler.go

@@ -12,6 +12,7 @@ type AdminHandlers struct {
 	Account          *admin.AccountHandler
 	Announcement     *admin.AnnouncementHandler
 	DataManagement   *admin.DataManagementHandler
+	Backup           *admin.BackupHandler
 	OAuth            *admin.OAuthHandler
 	OpenAIOAuth      *admin.OpenAIOAuthHandler
 	GeminiOAuth      *admin.GeminiOAuthHandler

backend/internal/handler/openai_chat_completions.go

@@ -0,0 +1,286 @@
+package handler
+
+import (
+	"context"
+	"errors"
+	"net/http"
+	"time"
+
+	pkghttputil "github.com/Wei-Shaw/sub2api/internal/pkg/httputil"
+	"github.com/Wei-Shaw/sub2api/internal/pkg/ip"
+	"github.com/Wei-Shaw/sub2api/internal/pkg/logger"
+	middleware2 "github.com/Wei-Shaw/sub2api/internal/server/middleware"
+	"github.com/Wei-Shaw/sub2api/internal/service"
+	"github.com/gin-gonic/gin"
+	"github.com/tidwall/gjson"
+	"go.uber.org/zap"
+)
+
+// ChatCompletions handles OpenAI Chat Completions API requests.
+// POST /v1/chat/completions
+func (h *OpenAIGatewayHandler) ChatCompletions(c *gin.Context) {
+	streamStarted := false
+	defer h.recoverResponsesPanic(c, &streamStarted)
+
+	requestStart := time.Now()
+
+	apiKey, ok := middleware2.GetAPIKeyFromContext(c)
+	if !ok {
+		h.errorResponse(c, http.StatusUnauthorized, "authentication_error", "Invalid API key")
+		return
+	}
+
+	subject, ok := middleware2.GetAuthSubjectFromContext(c)
+	if !ok {
+		h.errorResponse(c, http.StatusInternalServerError, "api_error", "User context not found")
+		return
+	}
+	reqLog := requestLogger(
+		c,
+		"handler.openai_gateway.chat_completions",
+		zap.Int64("user_id", subject.UserID),
+		zap.Int64("api_key_id", apiKey.ID),
+		zap.Any("group_id", apiKey.GroupID),
+	)
+
+	if !h.ensureResponsesDependencies(c, reqLog) {
+		return
+	}
+
+	body, err := pkghttputil.ReadRequestBodyWithPrealloc(c.Request)
+	if err != nil {
+		if maxErr, ok := extractMaxBytesError(err); ok {
+			h.errorResponse(c, http.StatusRequestEntityTooLarge, "invalid_request_error", buildBodyTooLargeMessage(maxErr.Limit))
+			return
+		}
+		h.errorResponse(c, http.StatusBadRequest, "invalid_request_error", "Failed to read request body")
+		return
+	}
+	if len(body) == 0 {
+		h.errorResponse(c, http.StatusBadRequest, "invalid_request_error", "Request body is empty")
+		return
+	}
+
+	if !gjson.ValidBytes(body) {
+		h.errorResponse(c, http.StatusBadRequest, "invalid_request_error", "Failed to parse request body")
+		return
+	}
+
+	modelResult := gjson.GetBytes(body, "model")
+	if !modelResult.Exists() || modelResult.Type != gjson.String || modelResult.String() == "" {
+		h.errorResponse(c, http.StatusBadRequest, "invalid_request_error", "model is required")
+		return
+	}
+	reqModel := modelResult.String()
+	reqStream := gjson.GetBytes(body, "stream").Bool()
+
+	reqLog = reqLog.With(zap.String("model", reqModel), zap.Bool("stream", reqStream))
+
+	setOpsRequestContext(c, reqModel, reqStream, body)
+
+	if h.errorPassthroughService != nil {
+		service.BindErrorPassthroughService(c, h.errorPassthroughService)
+	}
+
+	subscription, _ := middleware2.GetSubscriptionFromContext(c)
+
+	service.SetOpsLatencyMs(c, service.OpsAuthLatencyMsKey, time.Since(requestStart).Milliseconds())
+	routingStart := time.Now()
+
+	userReleaseFunc, acquired := h.acquireResponsesUserSlot(c, subject.UserID, subject.Concurrency, reqStream, &streamStarted, reqLog)
+	if !acquired {
+		return
+	}
+	if userReleaseFunc != nil {
+		defer userReleaseFunc()
+	}
+
+	if err := h.billingCacheService.CheckBillingEligibility(c.Request.Context(), apiKey.User, apiKey, apiKey.Group, subscription); err != nil {
+		reqLog.Info("openai_chat_completions.billing_eligibility_check_failed", zap.Error(err))
+		status, code, message := billingErrorDetails(err)
+		h.handleStreamingAwareError(c, status, code, message, streamStarted)
+		return
+	}
+
+	sessionHash := h.gatewayService.GenerateSessionHash(c, body)
+	promptCacheKey := h.gatewayService.ExtractSessionID(c, body)
+
+	maxAccountSwitches := h.maxAccountSwitches
+	switchCount := 0
+	failedAccountIDs := make(map[int64]struct{})
+	sameAccountRetryCount := make(map[int64]int)
+	var lastFailoverErr *service.UpstreamFailoverError
+
+	for {
+		c.Set("openai_chat_completions_fallback_model", "")
+		reqLog.Debug("openai_chat_completions.account_selecting", zap.Int("excluded_account_count", len(failedAccountIDs)))
+		selection, scheduleDecision, err := h.gatewayService.SelectAccountWithScheduler(
+			c.Request.Context(),
+			apiKey.GroupID,
+			"",
+			sessionHash,
+			reqModel,
+			failedAccountIDs,
+			service.OpenAIUpstreamTransportAny,
+		)
+		if err != nil {
+			reqLog.Warn("openai_chat_completions.account_select_failed",
+				zap.Error(err),
+				zap.Int("excluded_account_count", len(failedAccountIDs)),
+			)
+			if len(failedAccountIDs) == 0 {
+				defaultModel := ""
+				if apiKey.Group != nil {
+					defaultModel = apiKey.Group.DefaultMappedModel
+				}
+				if defaultModel != "" && defaultModel != reqModel {
+					reqLog.Info("openai_chat_completions.fallback_to_default_model",
+						zap.String("default_mapped_model", defaultModel),
+					)
+					selection, scheduleDecision, err = h.gatewayService.SelectAccountWithScheduler(
+						c.Request.Context(),
+						apiKey.GroupID,
+						"",
+						sessionHash,
+						defaultModel,
+						failedAccountIDs,
+						service.OpenAIUpstreamTransportAny,
+					)
+					if err == nil && selection != nil {
+						c.Set("openai_chat_completions_fallback_model", defaultModel)
+					}
+				}
+				if err != nil {
+					h.handleStreamingAwareError(c, http.StatusServiceUnavailable, "api_error", "Service temporarily unavailable", streamStarted)
+					return
+				}
+			} else {
+				if lastFailoverErr != nil {
+					h.handleFailoverExhausted(c, lastFailoverErr, streamStarted)
+				} else {
+					h.handleStreamingAwareError(c, http.StatusBadGateway, "api_error", "Upstream request failed", streamStarted)
+				}
+				return
+			}
+		}
+		if selection == nil || selection.Account == nil {
+			h.handleStreamingAwareError(c, http.StatusServiceUnavailable, "api_error", "No available accounts", streamStarted)
+			return
+		}
+		account := selection.Account
+		sessionHash = ensureOpenAIPoolModeSessionHash(sessionHash, account)
+		reqLog.Debug("openai_chat_completions.account_selected", zap.Int64("account_id", account.ID), zap.String("account_name", account.Name))
+		_ = scheduleDecision
+		setOpsSelectedAccount(c, account.ID, account.Platform)
+
+		accountReleaseFunc, acquired := h.acquireResponsesAccountSlot(c, apiKey.GroupID, sessionHash, selection, reqStream, &streamStarted, reqLog)
+		if !acquired {
+			return
+		}
+
+		service.SetOpsLatencyMs(c, service.OpsRoutingLatencyMsKey, time.Since(routingStart).Milliseconds())
+		forwardStart := time.Now()
+
+		defaultMappedModel := c.GetString("openai_chat_completions_fallback_model")
+		result, err := h.gatewayService.ForwardAsChatCompletions(c.Request.Context(), c, account, body, promptCacheKey, defaultMappedModel)
+
+		forwardDurationMs := time.Since(forwardStart).Milliseconds()
+		if accountReleaseFunc != nil {
+			accountReleaseFunc()
+		}
+		upstreamLatencyMs, _ := getContextInt64(c, service.OpsUpstreamLatencyMsKey)
+		responseLatencyMs := forwardDurationMs
+		if upstreamLatencyMs > 0 && forwardDurationMs > upstreamLatencyMs {
+			responseLatencyMs = forwardDurationMs - upstreamLatencyMs
+		}
+		service.SetOpsLatencyMs(c, service.OpsResponseLatencyMsKey, responseLatencyMs)
+		if err == nil && result != nil && result.FirstTokenMs != nil {
+			service.SetOpsLatencyMs(c, service.OpsTimeToFirstTokenMsKey, int64(*result.FirstTokenMs))
+		}
+		if err != nil {
+			var failoverErr *service.UpstreamFailoverError
+			if errors.As(err, &failoverErr) {
+				h.gatewayService.ReportOpenAIAccountScheduleResult(account.ID, false, nil)
+				// Pool mode: retry on the same account
+				if failoverErr.RetryableOnSameAccount {
+					retryLimit := account.GetPoolModeRetryCount()
+					if sameAccountRetryCount[account.ID] < retryLimit {
+						sameAccountRetryCount[account.ID]++
+						reqLog.Warn("openai_chat_completions.pool_mode_same_account_retry",
+							zap.Int64("account_id", account.ID),
+							zap.Int("upstream_status", failoverErr.StatusCode),
+							zap.Int("retry_limit", retryLimit),
+							zap.Int("retry_count", sameAccountRetryCount[account.ID]),
+						)
+						select {
+						case <-c.Request.Context().Done():
+							return
+						case <-time.After(sameAccountRetryDelay):
+						}
+						continue
+					}
+				}
+				h.gatewayService.RecordOpenAIAccountSwitch()
+				failedAccountIDs[account.ID] = struct{}{}
+				lastFailoverErr = failoverErr
+				if switchCount >= maxAccountSwitches {
+					h.handleFailoverExhausted(c, failoverErr, streamStarted)
+					return
+				}
+				switchCount++
+				reqLog.Warn("openai_chat_completions.upstream_failover_switching",
+					zap.Int64("account_id", account.ID),
+					zap.Int("upstream_status", failoverErr.StatusCode),
+					zap.Int("switch_count", switchCount),
+					zap.Int("max_switches", maxAccountSwitches),
+				)
+				continue
+			}
+			h.gatewayService.ReportOpenAIAccountScheduleResult(account.ID, false, nil)
+			wroteFallback := h.ensureForwardErrorResponse(c, streamStarted)
+			reqLog.Warn("openai_chat_completions.forward_failed",
+				zap.Int64("account_id", account.ID),
+				zap.Bool("fallback_error_response_written", wroteFallback),
+				zap.Error(err),
+			)
+			return
+		}
+		if result != nil {
+			h.gatewayService.ReportOpenAIAccountScheduleResult(account.ID, true, result.FirstTokenMs)
+		} else {
+			h.gatewayService.ReportOpenAIAccountScheduleResult(account.ID, true, nil)
+		}
+
+		userAgent := c.GetHeader("User-Agent")
+		clientIP := ip.GetClientIP(c)
+
+		h.submitUsageRecordTask(func(ctx context.Context) {
+			if err := h.gatewayService.RecordUsage(ctx, &service.OpenAIRecordUsageInput{
+				Result:           result,
+				APIKey:           apiKey,
+				User:             apiKey.User,
+				Account:          account,
+				Subscription:     subscription,
+				InboundEndpoint:  GetInboundEndpoint(c),
+				UpstreamEndpoint: GetUpstreamEndpoint(c, account.Platform),
+				UserAgent:        userAgent,
+				IPAddress:        clientIP,
+				APIKeyService:    h.apiKeyService,
+			}); err != nil {
+				logger.L().With(
+					zap.String("component", "handler.openai_gateway.chat_completions"),
+					zap.Int64("user_id", subject.UserID),
+					zap.Int64("api_key_id", apiKey.ID),
+					zap.Any("group_id", apiKey.GroupID),
+					zap.String("model", reqModel),
+					zap.Int64("account_id", account.ID),
+				).Error("openai_chat_completions.record_usage_failed", zap.Error(err))
+			}
+		})
+		reqLog.Debug("openai_chat_completions.request_completed",
+			zap.Int64("account_id", account.ID),
+			zap.Int("switch_count", switchCount),
+		)
+		return
+	}
+}

backend/internal/handler/openai_gateway_endpoint_normalization_test.go

@@ -0,0 +1,56 @@
+package handler
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/Wei-Shaw/sub2api/internal/service"
+	"github.com/gin-gonic/gin"
+	"github.com/stretchr/testify/require"
+)
+
+// TestOpenAIUpstreamEndpoint_ViaGetUpstreamEndpoint verifies that the
+// unified GetUpstreamEndpoint helper produces the same results as the
+// former normalizedOpenAIUpstreamEndpoint for OpenAI platform requests.
+func TestOpenAIUpstreamEndpoint_ViaGetUpstreamEndpoint(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+
+	tests := []struct {
+		name string
+		path string
+		want string
+	}{
+		{
+			name: "responses root maps to responses upstream",
+			path: "/v1/responses",
+			want: EndpointResponses,
+		},
+		{
+			name: "responses compact keeps compact suffix",
+			path: "/openai/v1/responses/compact",
+			want: "/v1/responses/compact",
+		},
+		{
+			name: "responses nested suffix preserved",
+			path: "/openai/v1/responses/compact/detail",
+			want: "/v1/responses/compact/detail",
+		},
+		{
+			name: "non responses path uses platform fallback",
+			path: "/v1/messages",
+			want: EndpointResponses,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			rec := httptest.NewRecorder()
+			c, _ := gin.CreateTestContext(rec)
+			c.Request = httptest.NewRequest(http.MethodPost, tt.path, nil)
+
+			got := GetUpstreamEndpoint(c, service.PlatformOpenAI)
+			require.Equal(t, tt.want, got)
+		})
+	}
+}

backend/internal/handler/openai_gateway_handler.go

@@ -352,18 +352,22 @@ func (h *OpenAIGatewayHandler) Responses(c *gin.Context) {
 		// 捕获请求信息（用于异步记录，避免在 goroutine 中访问 gin.Context）
 		userAgent := c.GetHeader("User-Agent")
 		clientIP := ip.GetClientIP(c)
+		requestPayloadHash := service.HashUsageRequestPayload(body)
 
 		// 使用量记录通过有界 worker 池提交，避免请求热路径创建无界 goroutine。
 		h.submitUsageRecordTask(func(ctx context.Context) {
 			if err := h.gatewayService.RecordUsage(ctx, &service.OpenAIRecordUsageInput{
-				Result:        result,
-				APIKey:        apiKey,
-				User:          apiKey.User,
-				Account:       account,
-				Subscription:  subscription,
-				UserAgent:     userAgent,
-				IPAddress:     clientIP,
-				APIKeyService: h.apiKeyService,
+				Result:             result,
+				APIKey:             apiKey,
+				User:               apiKey.User,
+				Account:            account,
+				Subscription:       subscription,
+				InboundEndpoint:    GetInboundEndpoint(c),
+				UpstreamEndpoint:   GetUpstreamEndpoint(c, account.Platform),
+				UserAgent:          userAgent,
+				IPAddress:          clientIP,
+				RequestPayloadHash: requestPayloadHash,
+				APIKeyService:      h.apiKeyService,
 			}); err != nil {
 				logger.L().With(
 					zap.String("component", "handler.openai_gateway.responses"),
@@ -653,14 +657,9 @@ func (h *OpenAIGatewayHandler) Messages(c *gin.Context) {
 		service.SetOpsLatencyMs(c, service.OpsRoutingLatencyMsKey, time.Since(routingStart).Milliseconds())
 		forwardStart := time.Now()
 
-		defaultMappedModel := ""
-		if apiKey.Group != nil {
-			defaultMappedModel = apiKey.Group.DefaultMappedModel
-		}
-		// 如果使用了降级模型调度，强制使用降级模型
-		if fallbackModel := c.GetString("openai_messages_fallback_model"); fallbackModel != "" {
-			defaultMappedModel = fallbackModel
-		}
+		// 仅在调度时实际触发了降级（原模型无可用账号、改用默认模型重试成功）时，
+		// 才将降级模型传给 Forward 层做模型替换；否则保持用户请求的原始模型。
+		defaultMappedModel := c.GetString("openai_messages_fallback_model")
 		result, err := h.gatewayService.ForwardAsAnthropic(c.Request.Context(), c, account, body, promptCacheKey, defaultMappedModel)
 
 		forwardDurationMs := time.Since(forwardStart).Milliseconds()
@@ -732,17 +731,21 @@ func (h *OpenAIGatewayHandler) Messages(c *gin.Context) {
 
 		userAgent := c.GetHeader("User-Agent")
 		clientIP := ip.GetClientIP(c)
+		requestPayloadHash := service.HashUsageRequestPayload(body)
 
 		h.submitUsageRecordTask(func(ctx context.Context) {
 			if err := h.gatewayService.RecordUsage(ctx, &service.OpenAIRecordUsageInput{
-				Result:        result,
-				APIKey:        apiKey,
-				User:          apiKey.User,
-				Account:       account,
-				Subscription:  subscription,
-				UserAgent:     userAgent,
-				IPAddress:     clientIP,
-				APIKeyService: h.apiKeyService,
+				Result:             result,
+				APIKey:             apiKey,
+				User:               apiKey.User,
+				Account:            account,
+				Subscription:       subscription,
+				InboundEndpoint:    GetInboundEndpoint(c),
+				UpstreamEndpoint:   GetUpstreamEndpoint(c, account.Platform),
+				UserAgent:          userAgent,
+				IPAddress:          clientIP,
+				RequestPayloadHash: requestPayloadHash,
+				APIKeyService:      h.apiKeyService,
 			}); err != nil {
 				logger.L().With(
 					zap.String("component", "handler.openai_gateway.messages"),
@@ -1231,14 +1234,17 @@ func (h *OpenAIGatewayHandler) ResponsesWebSocket(c *gin.Context) {
 			h.gatewayService.ReportOpenAIAccountScheduleResult(account.ID, true, result.FirstTokenMs)
 			h.submitUsageRecordTask(func(taskCtx context.Context) {
 				if err := h.gatewayService.RecordUsage(taskCtx, &service.OpenAIRecordUsageInput{
-					Result:        result,
-					APIKey:        apiKey,
-					User:          apiKey.User,
-					Account:       account,
-					Subscription:  subscription,
-					UserAgent:     userAgent,
-					IPAddress:     clientIP,
-					APIKeyService: h.apiKeyService,
+					Result:             result,
+					APIKey:             apiKey,
+					User:               apiKey.User,
+					Account:            account,
+					Subscription:       subscription,
+					InboundEndpoint:    GetInboundEndpoint(c),
+					UpstreamEndpoint:   GetUpstreamEndpoint(c, account.Platform),
+					UserAgent:          userAgent,
+					IPAddress:          clientIP,
+					RequestPayloadHash: service.HashUsageRequestPayload(firstMessage),
+					APIKeyService:      h.apiKeyService,
 				}); err != nil {
 					reqLog.Error("openai.websocket_record_usage_failed",
 						zap.Int64("account_id", account.ID),
@@ -1429,6 +1435,10 @@ func (h *OpenAIGatewayHandler) handleFailoverExhausted(c *gin.Context, failoverE
 		}
 	}
 
+	// 记录原始上游状态码，以便 ops 错误日志捕获真实的上游错误
+	upstreamMsg := service.ExtractUpstreamErrorMessage(responseBody)
+	service.SetOpsUpstreamError(c, statusCode, upstreamMsg, "")
+
 	// 使用默认的错误映射
 	status, errType, errMsg := h.mapUpstreamError(statusCode)
 	h.handleStreamingAwareError(c, status, errType, errMsg, streamStarted)
@@ -1437,6 +1447,7 @@ func (h *OpenAIGatewayHandler) handleFailoverExhausted(c *gin.Context, failoverE
 // handleFailoverExhaustedSimple 简化版本，用于没有响应体的情况
 func (h *OpenAIGatewayHandler) handleFailoverExhaustedSimple(c *gin.Context, statusCode int, streamStarted bool) {
 	status, errType, errMsg := h.mapUpstreamError(statusCode)
+	service.SetOpsUpstreamError(c, statusCode, errMsg, "")
 	h.handleStreamingAwareError(c, status, errType, errMsg, streamStarted)
 }
 

backend/internal/handler/ops_error_logger.go

@@ -26,11 +26,28 @@ const (
 	opsStreamKey      = "ops_stream"
 	opsRequestBodyKey = "ops_request_body"
 	opsAccountIDKey   = "ops_account_id"
+
+	// 错误过滤匹配常量 — shouldSkipOpsErrorLog 和错误分类共用
+	opsErrContextCanceled            = "context canceled"
+	opsErrNoAvailableAccounts        = "no available accounts"
+	opsErrInvalidAPIKey              = "invalid_api_key"
+	opsErrAPIKeyRequired             = "api_key_required"
+	opsErrInsufficientBalance        = "insufficient balance"
+	opsErrInsufficientAccountBalance = "insufficient account balance"
+	opsErrInsufficientQuota          = "insufficient_quota"
+
+	// 上游错误码常量 — 错误分类 (normalizeOpsErrorType / classifyOpsPhase / classifyOpsIsBusinessLimited)
+	opsCodeInsufficientBalance  = "INSUFFICIENT_BALANCE"
+	opsCodeUsageLimitExceeded   = "USAGE_LIMIT_EXCEEDED"
+	opsCodeSubscriptionNotFound = "SUBSCRIPTION_NOT_FOUND"
+	opsCodeSubscriptionInvalid  = "SUBSCRIPTION_INVALID"
+	opsCodeUserInactive         = "USER_INACTIVE"
 )
 
 const (
 	opsErrorLogTimeout      = 5 * time.Second
 	opsErrorLogDrainTimeout = 10 * time.Second
+	opsErrorLogBatchWindow  = 200 * time.Millisecond
 
 	opsErrorLogMinWorkerCount = 4
 	opsErrorLogMaxWorkerCount = 32
@@ -38,6 +55,7 @@ const (
 	opsErrorLogQueueSizePerWorker = 128
 	opsErrorLogMinQueueSize       = 256
 	opsErrorLogMaxQueueSize       = 8192
+	opsErrorLogBatchSize          = 32
 )
 
 type opsErrorLogJob struct {
@@ -82,27 +100,82 @@ func startOpsErrorLogWorkers() {
 	for i := 0; i < workerCount; i++ {
 		go func() {
 			defer opsErrorLogWorkersWg.Done()
-			for job := range opsErrorLogQueue {
-				opsErrorLogQueueLen.Add(-1)
-				if job.ops == nil || job.entry == nil {
-					continue
+			for {
+				job, ok := <-opsErrorLogQueue
+				if !ok {
+					return
 				}
-				func() {
-					defer func() {
-						if r := recover(); r != nil {
-							log.Printf("[OpsErrorLogger] worker panic: %v\n%s", r, debug.Stack())
+				opsErrorLogQueueLen.Add(-1)
+				batch := make([]opsErrorLogJob, 0, opsErrorLogBatchSize)
+				batch = append(batch, job)
+
+				timer := time.NewTimer(opsErrorLogBatchWindow)
+			batchLoop:
+				for len(batch) < opsErrorLogBatchSize {
+					select {
+					case nextJob, ok := <-opsErrorLogQueue:
+						if !ok {
+							if !timer.Stop() {
+								select {
+								case <-timer.C:
+								default:
+								}
+							}
+							flushOpsErrorLogBatch(batch)
+							return
 						}
-					}()
-					ctx, cancel := context.WithTimeout(context.Background(), opsErrorLogTimeout)
-					_ = job.ops.RecordError(ctx, job.entry, nil)
-					cancel()
-					opsErrorLogProcessed.Add(1)
-				}()
+						opsErrorLogQueueLen.Add(-1)
+						batch = append(batch, nextJob)
+					case <-timer.C:
+						break batchLoop
+					}
+				}
+				if !timer.Stop() {
+					select {
+					case <-timer.C:
+					default:
+					}
+				}
+				flushOpsErrorLogBatch(batch)
 			}
 		}()
 	}
 }
 
+func flushOpsErrorLogBatch(batch []opsErrorLogJob) {
+	if len(batch) == 0 {
+		return
+	}
+	defer func() {
+		if r := recover(); r != nil {
+			log.Printf("[OpsErrorLogger] worker panic: %v\n%s", r, debug.Stack())
+		}
+	}()
+
+	grouped := make(map[*service.OpsService][]*service.OpsInsertErrorLogInput, len(batch))
+	var processed int64
+	for _, job := range batch {
+		if job.ops == nil || job.entry == nil {
+			continue
+		}
+		grouped[job.ops] = append(grouped[job.ops], job.entry)
+		processed++
+	}
+	if processed == 0 {
+		return
+	}
+
+	for opsSvc, entries := range grouped {
+		if opsSvc == nil || len(entries) == 0 {
+			continue
+		}
+		ctx, cancel := context.WithTimeout(context.Background(), opsErrorLogTimeout)
+		_ = opsSvc.RecordErrorBatch(ctx, entries)
+		cancel()
+	}
+	opsErrorLogProcessed.Add(processed)
+}
+
 func enqueueOpsErrorLog(ops *service.OpsService, entry *service.OpsInsertErrorLogInput) {
 	if ops == nil || entry == nil {
 		return
@@ -967,9 +1040,9 @@ func normalizeOpsErrorType(errType string, code string) string {
 		return errType
 	}
 	switch strings.TrimSpace(code) {
-	case "INSUFFICIENT_BALANCE":
+	case opsCodeInsufficientBalance:
 		return "billing_error"
-	case "USAGE_LIMIT_EXCEEDED", "SUBSCRIPTION_NOT_FOUND", "SUBSCRIPTION_INVALID":
+	case opsCodeUsageLimitExceeded, opsCodeSubscriptionNotFound, opsCodeSubscriptionInvalid:
 		return "subscription_error"
 	default:
 		return "api_error"
@@ -981,7 +1054,7 @@ func classifyOpsPhase(errType, message, code string) string {
 	// Standardized phases: request|auth|routing|upstream|network|internal
 	// Map billing/concurrency/response => request; scheduling => routing.
 	switch strings.TrimSpace(code) {
-	case "INSUFFICIENT_BALANCE", "USAGE_LIMIT_EXCEEDED", "SUBSCRIPTION_NOT_FOUND", "SUBSCRIPTION_INVALID":
+	case opsCodeInsufficientBalance, opsCodeUsageLimitExceeded, opsCodeSubscriptionNotFound, opsCodeSubscriptionInvalid:
 		return "request"
 	}
 
@@ -1000,7 +1073,7 @@ func classifyOpsPhase(errType, message, code string) string {
 	case "upstream_error", "overloaded_error":
 		return "upstream"
 	case "api_error":
-		if strings.Contains(msg, "no available accounts") {
+		if strings.Contains(msg, opsErrNoAvailableAccounts) {
 			return "routing"
 		}
 		return "internal"
@@ -1046,7 +1119,7 @@ func classifyOpsIsRetryable(errType string, statusCode int) bool {
 
 func classifyOpsIsBusinessLimited(errType, phase, code string, status int, message string) bool {
 	switch strings.TrimSpace(code) {
-	case "INSUFFICIENT_BALANCE", "USAGE_LIMIT_EXCEEDED", "SUBSCRIPTION_NOT_FOUND", "SUBSCRIPTION_INVALID", "USER_INACTIVE":
+	case opsCodeInsufficientBalance, opsCodeUsageLimitExceeded, opsCodeSubscriptionNotFound, opsCodeSubscriptionInvalid, opsCodeUserInactive:
 		return true
 	}
 	if phase == "billing" || phase == "concurrency" {
@@ -1140,21 +1213,30 @@ func shouldSkipOpsErrorLog(ctx context.Context, ops *service.OpsService, message
 
 	// Check if context canceled errors should be ignored (client disconnects)
 	if settings.IgnoreContextCanceled {
-		if strings.Contains(msgLower, "context canceled") || strings.Contains(bodyLower, "context canceled") {
+		if strings.Contains(msgLower, opsErrContextCanceled) || strings.Contains(bodyLower, opsErrContextCanceled) {
 			return true
 		}
 	}
 
 	// Check if "no available accounts" errors should be ignored
 	if settings.IgnoreNoAvailableAccounts {
-		if strings.Contains(msgLower, "no available accounts") || strings.Contains(bodyLower, "no available accounts") {
+		if strings.Contains(msgLower, opsErrNoAvailableAccounts) || strings.Contains(bodyLower, opsErrNoAvailableAccounts) {
 			return true
 		}
 	}
 
 	// Check if invalid/missing API key errors should be ignored (user misconfiguration)
 	if settings.IgnoreInvalidApiKeyErrors {
-		if strings.Contains(bodyLower, "invalid_api_key") || strings.Contains(bodyLower, "api_key_required") {
+		if strings.Contains(bodyLower, opsErrInvalidAPIKey) || strings.Contains(bodyLower, opsErrAPIKeyRequired) {
+			return true
+		}
+	}
+
+	// Check if insufficient balance errors should be ignored
+	if settings.IgnoreInsufficientBalanceErrors {
+		if strings.Contains(bodyLower, opsErrInsufficientBalance) || strings.Contains(bodyLower, opsErrInsufficientAccountBalance) ||
+			strings.Contains(bodyLower, opsErrInsufficientQuota) ||
+			strings.Contains(msgLower, opsErrInsufficientBalance) || strings.Contains(msgLower, opsErrInsufficientAccountBalance) {
 			return true
 		}
 	}

backend/internal/handler/setting_handler.go

@@ -54,6 +54,7 @@ func (h *SettingHandler) GetPublicSettings(c *gin.Context) {
 		CustomMenuItems:                  dto.ParseUserVisibleMenuItems(settings.CustomMenuItems),
 		LinuxDoOAuthEnabled:              settings.LinuxDoOAuthEnabled,
 		SoraClientEnabled:                settings.SoraClientEnabled,
+		BackendModeEnabled:               settings.BackendModeEnabled,
 		Version:                          h.version,
 	})
 }

backend/internal/handler/sora_client_handler_test.go

@@ -2206,7 +2206,7 @@ func (s *stubSoraClientForHandler) GetVideoTask(_ context.Context, _ *service.Ac
 // newMinimalGatewayService 创建仅包含 accountRepo 的最小 GatewayService（用于测试 SelectAccountForModel）。
 func newMinimalGatewayService(accountRepo service.AccountRepository) *service.GatewayService {
 	return service.NewGatewayService(
-		accountRepo, nil, nil, nil, nil, nil, nil, nil,
+		accountRepo, nil, nil, nil, nil, nil, nil, nil, nil,
 		nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil,
 	)
 }

backend/internal/handler/sora_gateway_handler.go

@@ -399,17 +399,23 @@ func (h *SoraGatewayHandler) ChatCompletions(c *gin.Context) {
 
 		userAgent := c.GetHeader("User-Agent")
 		clientIP := ip.GetClientIP(c)
+		requestPayloadHash := service.HashUsageRequestPayload(body)
+		inboundEndpoint := GetInboundEndpoint(c)
+		upstreamEndpoint := GetUpstreamEndpoint(c, account.Platform)
 
 		// 使用量记录通过有界 worker 池提交，避免请求热路径创建无界 goroutine。
 		h.submitUsageRecordTask(func(ctx context.Context) {
 			if err := h.gatewayService.RecordUsage(ctx, &service.RecordUsageInput{
-				Result:       result,
-				APIKey:       apiKey,
-				User:         apiKey.User,
-				Account:      account,
-				Subscription: subscription,
-				UserAgent:    userAgent,
-				IPAddress:    clientIP,
+				Result:             result,
+				APIKey:             apiKey,
+				User:               apiKey.User,
+				Account:            account,
+				Subscription:       subscription,
+				InboundEndpoint:    inboundEndpoint,
+				UpstreamEndpoint:   upstreamEndpoint,
+				UserAgent:          userAgent,
+				IPAddress:          clientIP,
+				RequestPayloadHash: requestPayloadHash,
 			}); err != nil {
 				logger.L().With(
 					zap.String("component", "handler.sora_gateway.chat_completions"),
@@ -478,6 +484,9 @@ func (h *SoraGatewayHandler) handleConcurrencyError(c *gin.Context, err error, s
 }
 
 func (h *SoraGatewayHandler) handleFailoverExhausted(c *gin.Context, statusCode int, responseHeaders http.Header, responseBody []byte, streamStarted bool) {
+	upstreamMsg := service.ExtractUpstreamErrorMessage(responseBody)
+	service.SetOpsUpstreamError(c, statusCode, upstreamMsg, "")
+
 	status, errType, errMsg := h.mapUpstreamError(statusCode, responseHeaders, responseBody)
 	h.handleStreamingAwareError(c, status, errType, errMsg, streamStarted)
 }

backend/internal/handler/sora_gateway_handler_test.go

@@ -273,8 +273,8 @@ func (r *stubGroupRepo) ListActiveByPlatform(ctx context.Context, platform strin
 func (r *stubGroupRepo) ExistsByName(ctx context.Context, name string) (bool, error) {
 	return false, nil
 }
-func (r *stubGroupRepo) GetAccountCount(ctx context.Context, groupID int64) (int64, error) {
-	return 0, nil
+func (r *stubGroupRepo) GetAccountCount(ctx context.Context, groupID int64) (int64, int64, error) {
+	return 0, 0, nil
 }
 func (r *stubGroupRepo) DeleteAccountGroupsByGroupID(ctx context.Context, groupID int64) (int64, error) {
 	return 0, nil
@@ -334,15 +334,32 @@ func (s *stubUsageLogRepo) GetUsageTrendWithFilters(ctx context.Context, startTi
 func (s *stubUsageLogRepo) GetModelStatsWithFilters(ctx context.Context, startTime, endTime time.Time, userID, apiKeyID, accountID, groupID int64, requestType *int16, stream *bool, billingType *int8) ([]usagestats.ModelStat, error) {
 	return nil, nil
 }
+
+func (s *stubUsageLogRepo) GetEndpointStatsWithFilters(ctx context.Context, startTime, endTime time.Time, userID, apiKeyID, accountID, groupID int64, model string, requestType *int16, stream *bool, billingType *int8) ([]usagestats.EndpointStat, error) {
+	return []usagestats.EndpointStat{}, nil
+}
+
+func (s *stubUsageLogRepo) GetUpstreamEndpointStatsWithFilters(ctx context.Context, startTime, endTime time.Time, userID, apiKeyID, accountID, groupID int64, model string, requestType *int16, stream *bool, billingType *int8) ([]usagestats.EndpointStat, error) {
+	return []usagestats.EndpointStat{}, nil
+}
 func (s *stubUsageLogRepo) GetGroupStatsWithFilters(ctx context.Context, startTime, endTime time.Time, userID, apiKeyID, accountID, groupID int64, requestType *int16, stream *bool, billingType *int8) ([]usagestats.GroupStat, error) {
 	return nil, nil
 }
+func (s *stubUsageLogRepo) GetUserBreakdownStats(ctx context.Context, startTime, endTime time.Time, dim usagestats.UserBreakdownDimension, limit int) ([]usagestats.UserBreakdownItem, error) {
+	return nil, nil
+}
+func (s *stubUsageLogRepo) GetAllGroupUsageSummary(ctx context.Context, todayStart time.Time) ([]usagestats.GroupUsageSummary, error) {
+	return nil, nil
+}
 func (s *stubUsageLogRepo) GetAPIKeyUsageTrend(ctx context.Context, startTime, endTime time.Time, granularity string, limit int) ([]usagestats.APIKeyUsageTrendPoint, error) {
 	return nil, nil
 }
 func (s *stubUsageLogRepo) GetUserUsageTrend(ctx context.Context, startTime, endTime time.Time, granularity string, limit int) ([]usagestats.UserUsageTrendPoint, error) {
 	return nil, nil
 }
+func (s *stubUsageLogRepo) GetUserSpendingRanking(ctx context.Context, startTime, endTime time.Time, limit int) (*usagestats.UserSpendingRankingResponse, error) {
+	return nil, nil
+}
 func (s *stubUsageLogRepo) GetBatchUserUsageStats(ctx context.Context, userIDs []int64, startTime, endTime time.Time) (map[int64]*usagestats.BatchUserUsageStats, error) {
 	return nil, nil
 }
@@ -431,6 +448,7 @@ func TestSoraGatewayHandler_ChatCompletions(t *testing.T) {
 		nil,
 		nil,
 		nil,
+		nil,
 		testutil.StubGatewayCache{},
 		cfg,
 		nil,

backend/internal/handler/usage_handler.go

@@ -114,8 +114,8 @@ func (h *UsageHandler) List(c *gin.Context) {
 			response.BadRequest(c, "Invalid end_date format, use YYYY-MM-DD")
 			return
 		}
-		// Set end time to end of day
-		t = t.Add(24*time.Hour - time.Nanosecond)
+		// Use half-open range [start, end), move to next calendar day start (DST-safe).
+		t = t.AddDate(0, 0, 1)
 		endTime = &t
 	}
 
@@ -227,8 +227,8 @@ func (h *UsageHandler) Stats(c *gin.Context) {
 			response.BadRequest(c, "Invalid end_date format, use YYYY-MM-DD")
 			return
 		}
-		// 设置结束时间为当天结束
-		endTime = endTime.Add(24*time.Hour - time.Nanosecond)
+		// 与 SQL 条件 created_at < end 对齐，使用次日 00:00 作为上边界（DST-safe）。
+		endTime = endTime.AddDate(0, 0, 1)
 	} else {
 		// 使用 period 参数
 		period := c.DefaultQuery("period", "today")

backend/internal/handler/wire.go

@@ -15,6 +15,7 @@ func ProvideAdminHandlers(
 	accountHandler *admin.AccountHandler,
 	announcementHandler *admin.AnnouncementHandler,
 	dataManagementHandler *admin.DataManagementHandler,
+	backupHandler *admin.BackupHandler,
 	oauthHandler *admin.OAuthHandler,
 	openaiOAuthHandler *admin.OpenAIOAuthHandler,
 	geminiOAuthHandler *admin.GeminiOAuthHandler,
@@ -39,6 +40,7 @@ func ProvideAdminHandlers(
 		Account:          accountHandler,
 		Announcement:     announcementHandler,
 		DataManagement:   dataManagementHandler,
+		Backup:           backupHandler,
 		OAuth:            oauthHandler,
 		OpenAIOAuth:      openaiOAuthHandler,
 		GeminiOAuth:      geminiOAuthHandler,
@@ -128,6 +130,7 @@ var ProviderSet = wire.NewSet(
 	admin.NewAccountHandler,
 	admin.NewAnnouncementHandler,
 	admin.NewDataManagementHandler,
+	admin.NewBackupHandler,
 	admin.NewOAuthHandler,
 	admin.NewOpenAIOAuthHandler,
 	admin.NewGeminiOAuthHandler,

backend/internal/pkg/antigravity/claude_types.go

@@ -159,6 +159,8 @@ var claudeModels = []modelDef{
 // Antigravity 支持的 Gemini 模型
 var geminiModels = []modelDef{
 	{ID: "gemini-2.5-flash", DisplayName: "Gemini 2.5 Flash", CreatedAt: "2025-01-01T00:00:00Z"},
+	{ID: "gemini-2.5-flash-image", DisplayName: "Gemini 2.5 Flash Image", CreatedAt: "2025-01-01T00:00:00Z"},
+	{ID: "gemini-2.5-flash-image-preview", DisplayName: "Gemini 2.5 Flash Image Preview", CreatedAt: "2025-01-01T00:00:00Z"},
 	{ID: "gemini-2.5-flash-lite", DisplayName: "Gemini 2.5 Flash Lite", CreatedAt: "2025-01-01T00:00:00Z"},
 	{ID: "gemini-2.5-flash-thinking", DisplayName: "Gemini 2.5 Flash Thinking", CreatedAt: "2025-01-01T00:00:00Z"},
 	{ID: "gemini-3-flash", DisplayName: "Gemini 3 Flash", CreatedAt: "2025-06-01T00:00:00Z"},

backend/internal/pkg/antigravity/claude_types_test.go

@@ -13,6 +13,8 @@ func TestDefaultModels_ContainsNewAndLegacyImageModels(t *testing.T) {
 
 	requiredIDs := []string{
 		"claude-opus-4-6-thinking",
+		"gemini-2.5-flash-image",
+		"gemini-2.5-flash-image-preview",
 		"gemini-3.1-flash-image",
 		"gemini-3.1-flash-image-preview",
 		"gemini-3-pro-image", // legacy compatibility

backend/internal/pkg/antigravity/client.go

@@ -19,6 +19,16 @@ import (
 	"github.com/Wei-Shaw/sub2api/internal/pkg/proxyutil"
 )
 
+// ForbiddenError 表示上游返回 403 Forbidden
+type ForbiddenError struct {
+	StatusCode int
+	Body       string
+}
+
+func (e *ForbiddenError) Error() string {
+	return fmt.Sprintf("fetchAvailableModels 失败 (HTTP %d): %s", e.StatusCode, e.Body)
+}
+
 // NewAPIRequestWithURL 使用指定的 base URL 创建 Antigravity API 请求（v1internal 端点）
 func NewAPIRequestWithURL(ctx context.Context, baseURL, action, accessToken string, body []byte) (*http.Request, error) {
 	// 构建 URL，流式请求添加 ?alt=sse 参数
@@ -114,10 +124,68 @@ type IneligibleTier struct {
 type LoadCodeAssistResponse struct {
 	CloudAICompanionProject string            `json:"cloudaicompanionProject"`
 	CurrentTier             *TierInfo         `json:"currentTier,omitempty"`
-	PaidTier                *TierInfo         `json:"paidTier,omitempty"`
+	PaidTier                *PaidTierInfo     `json:"paidTier,omitempty"`
 	IneligibleTiers         []*IneligibleTier `json:"ineligibleTiers,omitempty"`
 }
 
+// PaidTierInfo 付费等级信息，包含 AI Credits 余额。
+type PaidTierInfo struct {
+	ID               string            `json:"id"`
+	Name             string            `json:"name"`
+	Description      string            `json:"description"`
+	AvailableCredits []AvailableCredit `json:"availableCredits,omitempty"`
+}
+
+// UnmarshalJSON 兼容 paidTier 既可能是字符串也可能是对象的情况。
+func (p *PaidTierInfo) UnmarshalJSON(data []byte) error {
+	data = bytes.TrimSpace(data)
+	if len(data) == 0 || string(data) == "null" {
+		return nil
+	}
+	if data[0] == '"' {
+		var id string
+		if err := json.Unmarshal(data, &id); err != nil {
+			return err
+		}
+		p.ID = id
+		return nil
+	}
+	type alias PaidTierInfo
+	var raw alias
+	if err := json.Unmarshal(data, &raw); err != nil {
+		return err
+	}
+	*p = PaidTierInfo(raw)
+	return nil
+}
+
+// AvailableCredit 表示一条 AI Credits 余额记录。
+type AvailableCredit struct {
+	CreditType                  string `json:"creditType,omitempty"`
+	CreditAmount                string `json:"creditAmount,omitempty"`
+	MinimumCreditAmountForUsage string `json:"minimumCreditAmountForUsage,omitempty"`
+}
+
+// GetAmount 将 creditAmount 解析为浮点数。
+func (c *AvailableCredit) GetAmount() float64 {
+	if c.CreditAmount == "" {
+		return 0
+	}
+	var value float64
+	_, _ = fmt.Sscanf(c.CreditAmount, "%f", &value)
+	return value
+}
+
+// GetMinimumAmount 将 minimumCreditAmountForUsage 解析为浮点数。
+func (c *AvailableCredit) GetMinimumAmount() float64 {
+	if c.MinimumCreditAmountForUsage == "" {
+		return 0
+	}
+	var value float64
+	_, _ = fmt.Sscanf(c.MinimumCreditAmountForUsage, "%f", &value)
+	return value
+}
+
 // OnboardUserRequest onboardUser 请求
 type OnboardUserRequest struct {
 	TierID   string `json:"tierId"`
@@ -147,6 +215,14 @@ func (r *LoadCodeAssistResponse) GetTier() string {
 	return ""
 }
 
+// GetAvailableCredits 返回 paid tier 中的 AI Credits 余额列表。
+func (r *LoadCodeAssistResponse) GetAvailableCredits() []AvailableCredit {
+	if r.PaidTier == nil {
+		return nil
+	}
+	return r.PaidTier.AvailableCredits
+}
+
 // Client Antigravity API 客户端
 type Client struct {
 	httpClient *http.Client
@@ -514,7 +590,20 @@ type ModelQuotaInfo struct {
 
 // ModelInfo 模型信息
 type ModelInfo struct {
-	QuotaInfo *ModelQuotaInfo `json:"quotaInfo,omitempty"`
+	QuotaInfo          *ModelQuotaInfo `json:"quotaInfo,omitempty"`
+	DisplayName        string          `json:"displayName,omitempty"`
+	SupportsImages     *bool           `json:"supportsImages,omitempty"`
+	SupportsThinking   *bool           `json:"supportsThinking,omitempty"`
+	ThinkingBudget     *int            `json:"thinkingBudget,omitempty"`
+	Recommended        *bool           `json:"recommended,omitempty"`
+	MaxTokens          *int            `json:"maxTokens,omitempty"`
+	MaxOutputTokens    *int            `json:"maxOutputTokens,omitempty"`
+	SupportedMimeTypes map[string]bool `json:"supportedMimeTypes,omitempty"`
+}
+
+// DeprecatedModelInfo 废弃模型转发信息
+type DeprecatedModelInfo struct {
+	NewModelID string `json:"newModelId"`
 }
 
 // FetchAvailableModelsRequest fetchAvailableModels 请求
@@ -524,7 +613,8 @@ type FetchAvailableModelsRequest struct {
 
 // FetchAvailableModelsResponse fetchAvailableModels 响应
 type FetchAvailableModelsResponse struct {
-	Models map[string]ModelInfo `json:"models"`
+	Models             map[string]ModelInfo           `json:"models"`
+	DeprecatedModelIDs map[string]DeprecatedModelInfo `json:"deprecatedModelIds,omitempty"`
 }
 
 // FetchAvailableModels 获取可用模型和配额信息，返回解析后的结构体和原始 JSON
@@ -573,6 +663,13 @@ func (c *Client) FetchAvailableModels(ctx context.Context, accessToken, projectI
 			continue
 		}
 
+		if resp.StatusCode == http.StatusForbidden {
+			return nil, nil, &ForbiddenError{
+				StatusCode: resp.StatusCode,
+				Body:       string(respBodyBytes),
+			}
+		}
+
 		if resp.StatusCode != http.StatusOK {
 			return nil, nil, fmt.Errorf("fetchAvailableModels 失败 (HTTP %d): %s", resp.StatusCode, string(respBodyBytes))
 		}

backend/internal/pkg/antigravity/client_test.go

@@ -190,7 +190,7 @@ func TestTierInfo_UnmarshalJSON_通过JSON嵌套结构(t *testing.T) {
 func TestGetTier_PaidTier优先(t *testing.T) {
 	resp := &LoadCodeAssistResponse{
 		CurrentTier: &TierInfo{ID: "free-tier"},
-		PaidTier:    &TierInfo{ID: "g1-pro-tier"},
+		PaidTier:    &PaidTierInfo{ID: "g1-pro-tier"},
 	}
 	if got := resp.GetTier(); got != "g1-pro-tier" {
 		t.Errorf("应返回 paidTier: got %s", got)
@@ -209,7 +209,7 @@ func TestGetTier_回退到CurrentTier(t *testing.T) {
 func TestGetTier_PaidTier为空ID(t *testing.T) {
 	resp := &LoadCodeAssistResponse{
 		CurrentTier: &TierInfo{ID: "free-tier"},
-		PaidTier:    &TierInfo{ID: ""},
+		PaidTier:    &PaidTierInfo{ID: ""},
 	}
 	// paidTier.ID 为空时应回退到 currentTier
 	if got := resp.GetTier(); got != "free-tier" {
@@ -217,6 +217,32 @@ func TestGetTier_PaidTier为空ID(t *testing.T) {
 	}
 }
 
+func TestGetAvailableCredits(t *testing.T) {
+	resp := &LoadCodeAssistResponse{
+		PaidTier: &PaidTierInfo{
+			ID: "g1-pro-tier",
+			AvailableCredits: []AvailableCredit{
+				{
+					CreditType:                  "GOOGLE_ONE_AI",
+					CreditAmount:                "25",
+					MinimumCreditAmountForUsage: "5",
+				},
+			},
+		},
+	}
+
+	credits := resp.GetAvailableCredits()
+	if len(credits) != 1 {
+		t.Fatalf("AI Credits 数量不匹配: got %d", len(credits))
+	}
+	if credits[0].GetAmount() != 25 {
+		t.Errorf("CreditAmount 解析不正确: got %v", credits[0].GetAmount())
+	}
+	if credits[0].GetMinimumAmount() != 5 {
+		t.Errorf("MinimumCreditAmountForUsage 解析不正确: got %v", credits[0].GetMinimumAmount())
+	}
+}
+
 func TestGetTier_两者都为nil(t *testing.T) {
 	resp := &LoadCodeAssistResponse{}
 	if got := resp.GetTier(); got != "" {

backend/internal/pkg/antigravity/gemini_types.go

@@ -189,6 +189,5 @@ var DefaultStopSequences = []string{
 	"<|user|>",
 	"<|endoftext|>",
 	"<|end_of_turn|>",
-	"[DONE]",
 	"\n\nHuman:",
 }

backend/internal/pkg/antigravity/oauth.go

@@ -49,8 +49,8 @@ const (
 	antigravityDailyBaseURL = "https://daily-cloudcode-pa.sandbox.googleapis.com"
 )
 
-// defaultUserAgentVersion 可通过环境变量 ANTIGRAVITY_USER_AGENT_VERSION 配置，默认 1.20.4
-var defaultUserAgentVersion = "1.20.4"
+// defaultUserAgentVersion 可通过环境变量 ANTIGRAVITY_USER_AGENT_VERSION 配置，默认 1.20.5
+var defaultUserAgentVersion = "1.20.5"
 
 // defaultClientSecret 可通过环境变量 ANTIGRAVITY_OAUTH_CLIENT_SECRET 配置
 var defaultClientSecret = "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"

backend/internal/pkg/antigravity/oauth_test.go

@@ -690,7 +690,7 @@ func TestConstants_值正确(t *testing.T) {
 	if RedirectURI != "http://localhost:8085/callback" {
 		t.Errorf("RedirectURI 不匹配: got %s", RedirectURI)
 	}
-	if GetUserAgent() != "antigravity/1.20.4 windows/amd64" {
+	if GetUserAgent() != "antigravity/1.20.5 windows/amd64" {
 		t.Errorf("UserAgent 不匹配: got %s", GetUserAgent())
 	}
 	if SessionTTL != 30*time.Minute {

backend/internal/pkg/antigravity/request_transformer.go

@@ -275,21 +275,6 @@ func filterOpenCodePrompt(text string) string {
 	return ""
 }
 
-// systemBlockFilterPrefixes 需要从 system 中过滤的文本前缀列表
-var systemBlockFilterPrefixes = []string{
-	"x-anthropic-billing-header",
-}
-
-// filterSystemBlockByPrefix 如果文本匹配过滤前缀，返回空字符串
-func filterSystemBlockByPrefix(text string) string {
-	for _, prefix := range systemBlockFilterPrefixes {
-		if strings.HasPrefix(text, prefix) {
-			return ""
-		}
-	}
-	return text
-}
-
 // buildSystemInstruction 构建 systemInstruction（与 Antigravity-Manager 保持一致）
 func buildSystemInstruction(system json.RawMessage, modelName string, opts TransformOptions, tools []ClaudeTool) *GeminiContent {
 	var parts []GeminiPart
@@ -306,8 +291,8 @@ func buildSystemInstruction(system json.RawMessage, modelName string, opts Trans
 				if strings.Contains(sysStr, "You are Antigravity") {
 					userHasAntigravityIdentity = true
 				}
-				// 过滤 OpenCode 默认提示词和黑名单前缀
-				filtered := filterSystemBlockByPrefix(filterOpenCodePrompt(sysStr))
+				// 过滤 OpenCode 默认提示词
+				filtered := filterOpenCodePrompt(sysStr)
 				if filtered != "" {
 					userSystemParts = append(userSystemParts, GeminiPart{Text: filtered})
 				}
@@ -321,8 +306,8 @@ func buildSystemInstruction(system json.RawMessage, modelName string, opts Trans
 						if strings.Contains(block.Text, "You are Antigravity") {
 							userHasAntigravityIdentity = true
 						}
-						// 过滤 OpenCode 默认提示词和黑名单前缀
-						filtered := filterSystemBlockByPrefix(filterOpenCodePrompt(block.Text))
+						// 过滤 OpenCode 默认提示词
+						filtered := filterOpenCodePrompt(block.Text)
 						if filtered != "" {
 							userSystemParts = append(userSystemParts, GeminiPart{Text: filtered})
 						}

backend/internal/pkg/antigravity/request_transformer_test.go

@@ -2,7 +2,10 @@ package antigravity
 
 import (
 	"encoding/json"
+	"strings"
 	"testing"
+
+	"github.com/stretchr/testify/require"
 )
 
 // TestBuildParts_ThinkingBlockWithoutSignature 测试thinking block无signature时的处理
@@ -349,3 +352,51 @@ func TestBuildGenerationConfig_ThinkingDynamicBudget(t *testing.T) {
 		})
 	}
 }
+
+func TestTransformClaudeToGeminiWithOptions_PreservesBillingHeaderSystemBlock(t *testing.T) {
+	tests := []struct {
+		name   string
+		system json.RawMessage
+	}{
+		{
+			name:   "system array",
+			system: json.RawMessage(`[{"type":"text","text":"x-anthropic-billing-header keep"}]`),
+		},
+		{
+			name:   "system string",
+			system: json.RawMessage(`"x-anthropic-billing-header keep"`),
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			claudeReq := &ClaudeRequest{
+				Model:  "claude-3-5-sonnet-latest",
+				System: tt.system,
+				Messages: []ClaudeMessage{
+					{
+						Role:    "user",
+						Content: json.RawMessage(`[{"type":"text","text":"hello"}]`),
+					},
+				},
+			}
+
+			body, err := TransformClaudeToGeminiWithOptions(claudeReq, "project-1", "gemini-2.5-flash", DefaultTransformOptions())
+			require.NoError(t, err)
+
+			var req V1InternalRequest
+			require.NoError(t, json.Unmarshal(body, &req))
+			require.NotNil(t, req.Request.SystemInstruction)
+
+			found := false
+			for _, part := range req.Request.SystemInstruction.Parts {
+				if strings.Contains(part.Text, "x-anthropic-billing-header keep") {
+					found = true
+					break
+				}
+			}
+
+			require.True(t, found, "转换后的 systemInstruction 应保留 x-anthropic-billing-header 内容")
+		})
+	}
+}

backend/internal/pkg/apicompat/anthropic_responses_test.go

@@ -105,6 +105,7 @@ func TestAnthropicToResponses_ToolUse(t *testing.T) {
 	assert.Equal(t, "assistant", items[1].Role)
 	assert.Equal(t, "function_call", items[2].Type)
 	assert.Equal(t, "fc_call_1", items[2].CallID)
+	assert.Empty(t, items[2].ID)
 	assert.Equal(t, "function_call_output", items[3].Type)
 	assert.Equal(t, "fc_call_1", items[3].CallID)
 	assert.Equal(t, "Sunny, 72°F", items[3].Output)
@@ -1007,3 +1008,114 @@ func TestAnthropicToResponses_ImageEmptyMediaType(t *testing.T) {
 	// Should default to image/png when media_type is empty.
 	assert.Equal(t, "data:image/png;base64,iVBOR", parts[0].ImageURL)
 }
+
+// ---------------------------------------------------------------------------
+// normalizeToolParameters tests
+// ---------------------------------------------------------------------------
+
+func TestNormalizeToolParameters(t *testing.T) {
+	tests := []struct {
+		name     string
+		input    json.RawMessage
+		expected string
+	}{
+		{
+			name:     "nil input",
+			input:    nil,
+			expected: `{"type":"object","properties":{}}`,
+		},
+		{
+			name:     "empty input",
+			input:    json.RawMessage(``),
+			expected: `{"type":"object","properties":{}}`,
+		},
+		{
+			name:     "null input",
+			input:    json.RawMessage(`null`),
+			expected: `{"type":"object","properties":{}}`,
+		},
+		{
+			name:     "object without properties",
+			input:    json.RawMessage(`{"type":"object"}`),
+			expected: `{"type":"object","properties":{}}`,
+		},
+		{
+			name:     "object with properties",
+			input:    json.RawMessage(`{"type":"object","properties":{"city":{"type":"string"}}}`),
+			expected: `{"type":"object","properties":{"city":{"type":"string"}}}`,
+		},
+		{
+			name:     "non-object type",
+			input:    json.RawMessage(`{"type":"string"}`),
+			expected: `{"type":"string"}`,
+		},
+		{
+			name:     "object with additional fields preserved",
+			input:    json.RawMessage(`{"type":"object","required":["name"]}`),
+			expected: `{"type":"object","required":["name"],"properties":{}}`,
+		},
+		{
+			name:     "invalid JSON passthrough",
+			input:    json.RawMessage(`not json`),
+			expected: `not json`,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := normalizeToolParameters(tt.input)
+			if tt.name == "invalid JSON passthrough" {
+				assert.Equal(t, tt.expected, string(result))
+			} else {
+				assert.JSONEq(t, tt.expected, string(result))
+			}
+		})
+	}
+}
+
+func TestAnthropicToResponses_ToolWithoutProperties(t *testing.T) {
+	req := &AnthropicRequest{
+		Model:     "gpt-5.2",
+		MaxTokens: 1024,
+		Messages: []AnthropicMessage{
+			{Role: "user", Content: json.RawMessage(`"Hello"`)},
+		},
+		Tools: []AnthropicTool{
+			{Name: "mcp__pencil__get_style_guide_tags", Description: "Get style tags", InputSchema: json.RawMessage(`{"type":"object"}`)},
+		},
+	}
+
+	resp, err := AnthropicToResponses(req)
+	require.NoError(t, err)
+
+	require.Len(t, resp.Tools, 1)
+	assert.Equal(t, "function", resp.Tools[0].Type)
+	assert.Equal(t, "mcp__pencil__get_style_guide_tags", resp.Tools[0].Name)
+
+	// Parameters must have "properties" field after normalization.
+	var params map[string]json.RawMessage
+	require.NoError(t, json.Unmarshal(resp.Tools[0].Parameters, &params))
+	assert.Contains(t, params, "properties")
+}
+
+func TestAnthropicToResponses_ToolWithNilSchema(t *testing.T) {
+	req := &AnthropicRequest{
+		Model:     "gpt-5.2",
+		MaxTokens: 1024,
+		Messages: []AnthropicMessage{
+			{Role: "user", Content: json.RawMessage(`"Hello"`)},
+		},
+		Tools: []AnthropicTool{
+			{Name: "simple_tool", Description: "A tool"},
+		},
+	}
+
+	resp, err := AnthropicToResponses(req)
+	require.NoError(t, err)
+
+	require.Len(t, resp.Tools, 1)
+	var params map[string]json.RawMessage
+	require.NoError(t, json.Unmarshal(resp.Tools[0].Parameters, &params))
+	assert.JSONEq(t, `"object"`, string(params["type"]))
+	assert.JSONEq(t, `{}`, string(params["properties"]))
+}

backend/internal/pkg/apicompat/anthropic_to_responses.go

@@ -277,7 +277,6 @@ func anthropicAssistantToResponses(raw json.RawMessage) ([]ResponsesInputItem, e
 			CallID:    fcID,
 			Name:      b.Name,
 			Arguments: args,
-			ID:        fcID,
 		})
 	}
 
@@ -410,8 +409,41 @@ func convertAnthropicToolsToResponses(tools []AnthropicTool) []ResponsesTool {
 			Type:        "function",
 			Name:        t.Name,
 			Description: t.Description,
-			Parameters:  t.InputSchema,
+			Parameters:  normalizeToolParameters(t.InputSchema),
 		})
 	}
 	return out
 }
+
+// normalizeToolParameters ensures the tool parameter schema is valid for
+// OpenAI's Responses API, which requires "properties" on object schemas.
+//
+//   - nil/empty → {"type":"object","properties":{}}
+//   - type=object without properties → adds "properties": {}
+//   - otherwise → returned unchanged
+func normalizeToolParameters(schema json.RawMessage) json.RawMessage {
+	if len(schema) == 0 || string(schema) == "null" {
+		return json.RawMessage(`{"type":"object","properties":{}}`)
+	}
+
+	var m map[string]json.RawMessage
+	if err := json.Unmarshal(schema, &m); err != nil {
+		return schema
+	}
+
+	typ := m["type"]
+	if string(typ) != `"object"` {
+		return schema
+	}
+
+	if _, ok := m["properties"]; ok {
+		return schema
+	}
+
+	m["properties"] = json.RawMessage(`{}`)
+	out, err := json.Marshal(m)
+	if err != nil {
+		return schema
+	}
+	return out
+}

backend/internal/pkg/apicompat/chatcompletions_responses_test.go

@@ -0,0 +1,810 @@
+package apicompat
+
+import (
+	"encoding/json"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+// ---------------------------------------------------------------------------
+// ChatCompletionsToResponses tests
+// ---------------------------------------------------------------------------
+
+func TestChatCompletionsToResponses_BasicText(t *testing.T) {
+	req := &ChatCompletionsRequest{
+		Model: "gpt-4o",
+		Messages: []ChatMessage{
+			{Role: "user", Content: json.RawMessage(`"Hello"`)},
+		},
+	}
+
+	resp, err := ChatCompletionsToResponses(req)
+	require.NoError(t, err)
+	assert.Equal(t, "gpt-4o", resp.Model)
+	assert.True(t, resp.Stream) // always forced true
+	assert.False(t, *resp.Store)
+
+	var items []ResponsesInputItem
+	require.NoError(t, json.Unmarshal(resp.Input, &items))
+	require.Len(t, items, 1)
+	assert.Equal(t, "user", items[0].Role)
+}
+
+func TestChatCompletionsToResponses_SystemMessage(t *testing.T) {
+	req := &ChatCompletionsRequest{
+		Model: "gpt-4o",
+		Messages: []ChatMessage{
+			{Role: "system", Content: json.RawMessage(`"You are helpful."`)},
+			{Role: "user", Content: json.RawMessage(`"Hi"`)},
+		},
+	}
+
+	resp, err := ChatCompletionsToResponses(req)
+	require.NoError(t, err)
+
+	var items []ResponsesInputItem
+	require.NoError(t, json.Unmarshal(resp.Input, &items))
+	require.Len(t, items, 2)
+	assert.Equal(t, "system", items[0].Role)
+	assert.Equal(t, "user", items[1].Role)
+}
+
+func TestChatCompletionsToResponses_ToolCalls(t *testing.T) {
+	req := &ChatCompletionsRequest{
+		Model: "gpt-4o",
+		Messages: []ChatMessage{
+			{Role: "user", Content: json.RawMessage(`"Call the function"`)},
+			{
+				Role: "assistant",
+				ToolCalls: []ChatToolCall{
+					{
+						ID:   "call_1",
+						Type: "function",
+						Function: ChatFunctionCall{
+							Name:      "ping",
+							Arguments: `{"host":"example.com"}`,
+						},
+					},
+				},
+			},
+			{
+				Role:       "tool",
+				ToolCallID: "call_1",
+				Content:    json.RawMessage(`"pong"`),
+			},
+		},
+		Tools: []ChatTool{
+			{
+				Type: "function",
+				Function: &ChatFunction{
+					Name:        "ping",
+					Description: "Ping a host",
+					Parameters:  json.RawMessage(`{"type":"object"}`),
+				},
+			},
+		},
+	}
+
+	resp, err := ChatCompletionsToResponses(req)
+	require.NoError(t, err)
+
+	var items []ResponsesInputItem
+	require.NoError(t, json.Unmarshal(resp.Input, &items))
+	// user + function_call + function_call_output = 3
+	// (assistant message with empty content + tool_calls → only function_call items emitted)
+	require.Len(t, items, 3)
+
+	// Check function_call item
+	assert.Equal(t, "function_call", items[1].Type)
+	assert.Equal(t, "call_1", items[1].CallID)
+	assert.Empty(t, items[1].ID)
+	assert.Equal(t, "ping", items[1].Name)
+
+	// Check function_call_output item
+	assert.Equal(t, "function_call_output", items[2].Type)
+	assert.Equal(t, "call_1", items[2].CallID)
+	assert.Equal(t, "pong", items[2].Output)
+
+	// Check tools
+	require.Len(t, resp.Tools, 1)
+	assert.Equal(t, "function", resp.Tools[0].Type)
+	assert.Equal(t, "ping", resp.Tools[0].Name)
+}
+
+func TestChatCompletionsToResponses_MaxTokens(t *testing.T) {
+	t.Run("max_tokens", func(t *testing.T) {
+		maxTokens := 100
+		req := &ChatCompletionsRequest{
+			Model:     "gpt-4o",
+			MaxTokens: &maxTokens,
+			Messages:  []ChatMessage{{Role: "user", Content: json.RawMessage(`"Hi"`)}},
+		}
+		resp, err := ChatCompletionsToResponses(req)
+		require.NoError(t, err)
+		require.NotNil(t, resp.MaxOutputTokens)
+		// Below minMaxOutputTokens (128), should be clamped
+		assert.Equal(t, minMaxOutputTokens, *resp.MaxOutputTokens)
+	})
+
+	t.Run("max_completion_tokens_preferred", func(t *testing.T) {
+		maxTokens := 100
+		maxCompletion := 500
+		req := &ChatCompletionsRequest{
+			Model:               "gpt-4o",
+			MaxTokens:           &maxTokens,
+			MaxCompletionTokens: &maxCompletion,
+			Messages:            []ChatMessage{{Role: "user", Content: json.RawMessage(`"Hi"`)}},
+		}
+		resp, err := ChatCompletionsToResponses(req)
+		require.NoError(t, err)
+		require.NotNil(t, resp.MaxOutputTokens)
+		assert.Equal(t, 500, *resp.MaxOutputTokens)
+	})
+}
+
+func TestChatCompletionsToResponses_ReasoningEffort(t *testing.T) {
+	req := &ChatCompletionsRequest{
+		Model:           "gpt-4o",
+		ReasoningEffort: "high",
+		Messages:        []ChatMessage{{Role: "user", Content: json.RawMessage(`"Hi"`)}},
+	}
+	resp, err := ChatCompletionsToResponses(req)
+	require.NoError(t, err)
+	require.NotNil(t, resp.Reasoning)
+	assert.Equal(t, "high", resp.Reasoning.Effort)
+	assert.Equal(t, "auto", resp.Reasoning.Summary)
+}
+
+func TestChatCompletionsToResponses_ImageURL(t *testing.T) {
+	content := `[{"type":"text","text":"Describe this"},{"type":"image_url","image_url":{"url":"data:image/png;base64,abc123"}}]`
+	req := &ChatCompletionsRequest{
+		Model: "gpt-4o",
+		Messages: []ChatMessage{
+			{Role: "user", Content: json.RawMessage(content)},
+		},
+	}
+	resp, err := ChatCompletionsToResponses(req)
+	require.NoError(t, err)
+
+	var items []ResponsesInputItem
+	require.NoError(t, json.Unmarshal(resp.Input, &items))
+	require.Len(t, items, 1)
+
+	var parts []ResponsesContentPart
+	require.NoError(t, json.Unmarshal(items[0].Content, &parts))
+	require.Len(t, parts, 2)
+	assert.Equal(t, "input_text", parts[0].Type)
+	assert.Equal(t, "Describe this", parts[0].Text)
+	assert.Equal(t, "input_image", parts[1].Type)
+	assert.Equal(t, "data:image/png;base64,abc123", parts[1].ImageURL)
+}
+
+func TestChatCompletionsToResponses_LegacyFunctions(t *testing.T) {
+	req := &ChatCompletionsRequest{
+		Model: "gpt-4o",
+		Messages: []ChatMessage{
+			{Role: "user", Content: json.RawMessage(`"Hi"`)},
+		},
+		Functions: []ChatFunction{
+			{
+				Name:        "get_weather",
+				Description: "Get weather",
+				Parameters:  json.RawMessage(`{"type":"object"}`),
+			},
+		},
+		FunctionCall: json.RawMessage(`{"name":"get_weather"}`),
+	}
+
+	resp, err := ChatCompletionsToResponses(req)
+	require.NoError(t, err)
+	require.Len(t, resp.Tools, 1)
+	assert.Equal(t, "function", resp.Tools[0].Type)
+	assert.Equal(t, "get_weather", resp.Tools[0].Name)
+
+	// tool_choice should be converted
+	require.NotNil(t, resp.ToolChoice)
+	var tc map[string]any
+	require.NoError(t, json.Unmarshal(resp.ToolChoice, &tc))
+	assert.Equal(t, "function", tc["type"])
+}
+
+func TestChatCompletionsToResponses_ServiceTier(t *testing.T) {
+	req := &ChatCompletionsRequest{
+		Model:       "gpt-4o",
+		ServiceTier: "flex",
+		Messages:    []ChatMessage{{Role: "user", Content: json.RawMessage(`"Hi"`)}},
+	}
+	resp, err := ChatCompletionsToResponses(req)
+	require.NoError(t, err)
+	assert.Equal(t, "flex", resp.ServiceTier)
+}
+
+func TestChatCompletionsToResponses_AssistantWithTextAndToolCalls(t *testing.T) {
+	req := &ChatCompletionsRequest{
+		Model: "gpt-4o",
+		Messages: []ChatMessage{
+			{Role: "user", Content: json.RawMessage(`"Do something"`)},
+			{
+				Role:    "assistant",
+				Content: json.RawMessage(`"Let me call a function."`),
+				ToolCalls: []ChatToolCall{
+					{
+						ID:   "call_abc",
+						Type: "function",
+						Function: ChatFunctionCall{
+							Name:      "do_thing",
+							Arguments: `{}`,
+						},
+					},
+				},
+			},
+		},
+	}
+
+	resp, err := ChatCompletionsToResponses(req)
+	require.NoError(t, err)
+
+	var items []ResponsesInputItem
+	require.NoError(t, json.Unmarshal(resp.Input, &items))
+	// user + assistant message (with text) + function_call
+	require.Len(t, items, 3)
+	assert.Equal(t, "user", items[0].Role)
+	assert.Equal(t, "assistant", items[1].Role)
+	assert.Equal(t, "function_call", items[2].Type)
+	assert.Empty(t, items[2].ID)
+}
+
+func TestChatCompletionsToResponses_AssistantArrayContentPreserved(t *testing.T) {
+	req := &ChatCompletionsRequest{
+		Model: "gpt-4o",
+		Messages: []ChatMessage{
+			{Role: "user", Content: json.RawMessage(`"Hi"`)},
+			{Role: "assistant", Content: json.RawMessage(`[{"type":"text","text":"A"},{"type":"text","text":"B"}]`)},
+		},
+	}
+
+	resp, err := ChatCompletionsToResponses(req)
+	require.NoError(t, err)
+
+	var items []ResponsesInputItem
+	require.NoError(t, json.Unmarshal(resp.Input, &items))
+	require.Len(t, items, 2)
+	assert.Equal(t, "assistant", items[1].Role)
+
+	var parts []ResponsesContentPart
+	require.NoError(t, json.Unmarshal(items[1].Content, &parts))
+	require.Len(t, parts, 1)
+	assert.Equal(t, "output_text", parts[0].Type)
+	assert.Equal(t, "AB", parts[0].Text)
+}
+
+func TestChatCompletionsToResponses_AssistantThinkingTagPreserved(t *testing.T) {
+	req := &ChatCompletionsRequest{
+		Model: "gpt-4o",
+		Messages: []ChatMessage{
+			{Role: "user", Content: json.RawMessage(`"Hi"`)},
+			{Role: "assistant", Content: json.RawMessage(`[{"type":"thinking","thinking":"internal plan"},{"type":"text","text":"final answer"}]`)},
+		},
+	}
+
+	resp, err := ChatCompletionsToResponses(req)
+	require.NoError(t, err)
+
+	var items []ResponsesInputItem
+	require.NoError(t, json.Unmarshal(resp.Input, &items))
+	require.Len(t, items, 2)
+
+	var parts []ResponsesContentPart
+	require.NoError(t, json.Unmarshal(items[1].Content, &parts))
+	require.Len(t, parts, 1)
+	assert.Equal(t, "output_text", parts[0].Type)
+	assert.Contains(t, parts[0].Text, "<thinking>internal plan</thinking>")
+	assert.Contains(t, parts[0].Text, "final answer")
+}
+
+// ---------------------------------------------------------------------------
+// ResponsesToChatCompletions tests
+// ---------------------------------------------------------------------------
+
+func TestResponsesToChatCompletions_BasicText(t *testing.T) {
+	resp := &ResponsesResponse{
+		ID:     "resp_123",
+		Status: "completed",
+		Output: []ResponsesOutput{
+			{
+				Type: "message",
+				Content: []ResponsesContentPart{
+					{Type: "output_text", Text: "Hello, world!"},
+				},
+			},
+		},
+		Usage: &ResponsesUsage{
+			InputTokens:  10,
+			OutputTokens: 5,
+			TotalTokens:  15,
+		},
+	}
+
+	chat := ResponsesToChatCompletions(resp, "gpt-4o")
+	assert.Equal(t, "chat.completion", chat.Object)
+	assert.Equal(t, "gpt-4o", chat.Model)
+	require.Len(t, chat.Choices, 1)
+	assert.Equal(t, "stop", chat.Choices[0].FinishReason)
+
+	var content string
+	require.NoError(t, json.Unmarshal(chat.Choices[0].Message.Content, &content))
+	assert.Equal(t, "Hello, world!", content)
+
+	require.NotNil(t, chat.Usage)
+	assert.Equal(t, 10, chat.Usage.PromptTokens)
+	assert.Equal(t, 5, chat.Usage.CompletionTokens)
+	assert.Equal(t, 15, chat.Usage.TotalTokens)
+}
+
+func TestResponsesToChatCompletions_ToolCalls(t *testing.T) {
+	resp := &ResponsesResponse{
+		ID:     "resp_456",
+		Status: "completed",
+		Output: []ResponsesOutput{
+			{
+				Type:      "function_call",
+				CallID:    "call_xyz",
+				Name:      "get_weather",
+				Arguments: `{"city":"NYC"}`,
+			},
+		},
+	}
+
+	chat := ResponsesToChatCompletions(resp, "gpt-4o")
+	require.Len(t, chat.Choices, 1)
+	assert.Equal(t, "tool_calls", chat.Choices[0].FinishReason)
+
+	msg := chat.Choices[0].Message
+	require.Len(t, msg.ToolCalls, 1)
+	assert.Equal(t, "call_xyz", msg.ToolCalls[0].ID)
+	assert.Equal(t, "function", msg.ToolCalls[0].Type)
+	assert.Equal(t, "get_weather", msg.ToolCalls[0].Function.Name)
+	assert.Equal(t, `{"city":"NYC"}`, msg.ToolCalls[0].Function.Arguments)
+}
+
+func TestResponsesToChatCompletions_Reasoning(t *testing.T) {
+	resp := &ResponsesResponse{
+		ID:     "resp_789",
+		Status: "completed",
+		Output: []ResponsesOutput{
+			{
+				Type: "reasoning",
+				Summary: []ResponsesSummary{
+					{Type: "summary_text", Text: "I thought about it."},
+				},
+			},
+			{
+				Type: "message",
+				Content: []ResponsesContentPart{
+					{Type: "output_text", Text: "The answer is 42."},
+				},
+			},
+		},
+	}
+
+	chat := ResponsesToChatCompletions(resp, "gpt-4o")
+	require.Len(t, chat.Choices, 1)
+
+	var content string
+	require.NoError(t, json.Unmarshal(chat.Choices[0].Message.Content, &content))
+	assert.Equal(t, "The answer is 42.", content)
+	assert.Equal(t, "I thought about it.", chat.Choices[0].Message.ReasoningContent)
+}
+
+func TestResponsesToChatCompletions_Incomplete(t *testing.T) {
+	resp := &ResponsesResponse{
+		ID:                "resp_inc",
+		Status:            "incomplete",
+		IncompleteDetails: &ResponsesIncompleteDetails{Reason: "max_output_tokens"},
+		Output: []ResponsesOutput{
+			{
+				Type: "message",
+				Content: []ResponsesContentPart{
+					{Type: "output_text", Text: "partial..."},
+				},
+			},
+		},
+	}
+
+	chat := ResponsesToChatCompletions(resp, "gpt-4o")
+	require.Len(t, chat.Choices, 1)
+	assert.Equal(t, "length", chat.Choices[0].FinishReason)
+}
+
+func TestResponsesToChatCompletions_CachedTokens(t *testing.T) {
+	resp := &ResponsesResponse{
+		ID:     "resp_cache",
+		Status: "completed",
+		Output: []ResponsesOutput{
+			{
+				Type:    "message",
+				Content: []ResponsesContentPart{{Type: "output_text", Text: "cached"}},
+			},
+		},
+		Usage: &ResponsesUsage{
+			InputTokens:  100,
+			OutputTokens: 10,
+			TotalTokens:  110,
+			InputTokensDetails: &ResponsesInputTokensDetails{
+				CachedTokens: 80,
+			},
+		},
+	}
+
+	chat := ResponsesToChatCompletions(resp, "gpt-4o")
+	require.NotNil(t, chat.Usage)
+	require.NotNil(t, chat.Usage.PromptTokensDetails)
+	assert.Equal(t, 80, chat.Usage.PromptTokensDetails.CachedTokens)
+}
+
+func TestResponsesToChatCompletions_WebSearch(t *testing.T) {
+	resp := &ResponsesResponse{
+		ID:     "resp_ws",
+		Status: "completed",
+		Output: []ResponsesOutput{
+			{
+				Type:   "web_search_call",
+				Action: &WebSearchAction{Type: "search", Query: "test"},
+			},
+			{
+				Type:    "message",
+				Content: []ResponsesContentPart{{Type: "output_text", Text: "search results"}},
+			},
+		},
+	}
+
+	chat := ResponsesToChatCompletions(resp, "gpt-4o")
+	require.Len(t, chat.Choices, 1)
+	assert.Equal(t, "stop", chat.Choices[0].FinishReason)
+
+	var content string
+	require.NoError(t, json.Unmarshal(chat.Choices[0].Message.Content, &content))
+	assert.Equal(t, "search results", content)
+}
+
+// ---------------------------------------------------------------------------
+// Streaming: ResponsesEventToChatChunks tests
+// ---------------------------------------------------------------------------
+
+func TestResponsesEventToChatChunks_TextDelta(t *testing.T) {
+	state := NewResponsesEventToChatState()
+	state.Model = "gpt-4o"
+
+	// response.created → role chunk
+	chunks := ResponsesEventToChatChunks(&ResponsesStreamEvent{
+		Type: "response.created",
+		Response: &ResponsesResponse{
+			ID: "resp_stream",
+		},
+	}, state)
+	require.Len(t, chunks, 1)
+	assert.Equal(t, "assistant", chunks[0].Choices[0].Delta.Role)
+	assert.True(t, state.SentRole)
+
+	// response.output_text.delta → content chunk
+	chunks = ResponsesEventToChatChunks(&ResponsesStreamEvent{
+		Type:  "response.output_text.delta",
+		Delta: "Hello",
+	}, state)
+	require.Len(t, chunks, 1)
+	require.NotNil(t, chunks[0].Choices[0].Delta.Content)
+	assert.Equal(t, "Hello", *chunks[0].Choices[0].Delta.Content)
+}
+
+func TestResponsesEventToChatChunks_ToolCallDelta(t *testing.T) {
+	state := NewResponsesEventToChatState()
+	state.Model = "gpt-4o"
+	state.SentRole = true
+
+	// response.output_item.added (function_call) — output_index=1 (e.g. after a message item at 0)
+	chunks := ResponsesEventToChatChunks(&ResponsesStreamEvent{
+		Type:        "response.output_item.added",
+		OutputIndex: 1,
+		Item: &ResponsesOutput{
+			Type:   "function_call",
+			CallID: "call_1",
+			Name:   "get_weather",
+		},
+	}, state)
+	require.Len(t, chunks, 1)
+	require.Len(t, chunks[0].Choices[0].Delta.ToolCalls, 1)
+	tc := chunks[0].Choices[0].Delta.ToolCalls[0]
+	assert.Equal(t, "call_1", tc.ID)
+	assert.Equal(t, "get_weather", tc.Function.Name)
+	require.NotNil(t, tc.Index)
+	assert.Equal(t, 0, *tc.Index)
+
+	// response.function_call_arguments.delta — uses output_index (NOT call_id) to find tool
+	chunks = ResponsesEventToChatChunks(&ResponsesStreamEvent{
+		Type:        "response.function_call_arguments.delta",
+		OutputIndex: 1, // matches the output_index from output_item.added above
+		Delta:       `{"city":`,
+	}, state)
+	require.Len(t, chunks, 1)
+	tc = chunks[0].Choices[0].Delta.ToolCalls[0]
+	require.NotNil(t, tc.Index)
+	assert.Equal(t, 0, *tc.Index, "argument delta must use same index as the tool call")
+	assert.Equal(t, `{"city":`, tc.Function.Arguments)
+
+	// Add a second function call at output_index=2
+	chunks = ResponsesEventToChatChunks(&ResponsesStreamEvent{
+		Type:        "response.output_item.added",
+		OutputIndex: 2,
+		Item: &ResponsesOutput{
+			Type:   "function_call",
+			CallID: "call_2",
+			Name:   "get_time",
+		},
+	}, state)
+	require.Len(t, chunks, 1)
+	tc = chunks[0].Choices[0].Delta.ToolCalls[0]
+	require.NotNil(t, tc.Index)
+	assert.Equal(t, 1, *tc.Index, "second tool call should get index 1")
+
+	// Argument delta for second tool call
+	chunks = ResponsesEventToChatChunks(&ResponsesStreamEvent{
+		Type:        "response.function_call_arguments.delta",
+		OutputIndex: 2,
+		Delta:       `{"tz":"UTC"}`,
+	}, state)
+	require.Len(t, chunks, 1)
+	tc = chunks[0].Choices[0].Delta.ToolCalls[0]
+	require.NotNil(t, tc.Index)
+	assert.Equal(t, 1, *tc.Index, "second tool arg delta must use index 1")
+
+	// Argument delta for first tool call (interleaved)
+	chunks = ResponsesEventToChatChunks(&ResponsesStreamEvent{
+		Type:        "response.function_call_arguments.delta",
+		OutputIndex: 1,
+		Delta:       `"Tokyo"}`,
+	}, state)
+	require.Len(t, chunks, 1)
+	tc = chunks[0].Choices[0].Delta.ToolCalls[0]
+	require.NotNil(t, tc.Index)
+	assert.Equal(t, 0, *tc.Index, "first tool arg delta must still use index 0")
+}
+
+func TestResponsesEventToChatChunks_Completed(t *testing.T) {
+	state := NewResponsesEventToChatState()
+	state.Model = "gpt-4o"
+	state.IncludeUsage = true
+
+	chunks := ResponsesEventToChatChunks(&ResponsesStreamEvent{
+		Type: "response.completed",
+		Response: &ResponsesResponse{
+			Status: "completed",
+			Usage: &ResponsesUsage{
+				InputTokens:  50,
+				OutputTokens: 20,
+				TotalTokens:  70,
+				InputTokensDetails: &ResponsesInputTokensDetails{
+					CachedTokens: 30,
+				},
+			},
+		},
+	}, state)
+	// finish chunk + usage chunk
+	require.Len(t, chunks, 2)
+
+	// First chunk: finish_reason
+	require.NotNil(t, chunks[0].Choices[0].FinishReason)
+	assert.Equal(t, "stop", *chunks[0].Choices[0].FinishReason)
+
+	// Second chunk: usage
+	require.NotNil(t, chunks[1].Usage)
+	assert.Equal(t, 50, chunks[1].Usage.PromptTokens)
+	assert.Equal(t, 20, chunks[1].Usage.CompletionTokens)
+	assert.Equal(t, 70, chunks[1].Usage.TotalTokens)
+	require.NotNil(t, chunks[1].Usage.PromptTokensDetails)
+	assert.Equal(t, 30, chunks[1].Usage.PromptTokensDetails.CachedTokens)
+}
+
+func TestResponsesEventToChatChunks_CompletedWithToolCalls(t *testing.T) {
+	state := NewResponsesEventToChatState()
+	state.Model = "gpt-4o"
+	state.SawToolCall = true
+
+	chunks := ResponsesEventToChatChunks(&ResponsesStreamEvent{
+		Type: "response.completed",
+		Response: &ResponsesResponse{
+			Status: "completed",
+		},
+	}, state)
+	require.Len(t, chunks, 1)
+	require.NotNil(t, chunks[0].Choices[0].FinishReason)
+	assert.Equal(t, "tool_calls", *chunks[0].Choices[0].FinishReason)
+}
+
+func TestResponsesEventToChatChunks_ReasoningDelta(t *testing.T) {
+	state := NewResponsesEventToChatState()
+	state.Model = "gpt-4o"
+	state.SentRole = true
+
+	chunks := ResponsesEventToChatChunks(&ResponsesStreamEvent{
+		Type:  "response.reasoning_summary_text.delta",
+		Delta: "Thinking...",
+	}, state)
+	require.Len(t, chunks, 1)
+	require.NotNil(t, chunks[0].Choices[0].Delta.ReasoningContent)
+	assert.Equal(t, "Thinking...", *chunks[0].Choices[0].Delta.ReasoningContent)
+
+	chunks = ResponsesEventToChatChunks(&ResponsesStreamEvent{
+		Type: "response.reasoning_summary_text.done",
+	}, state)
+	require.Len(t, chunks, 0)
+}
+
+func TestResponsesEventToChatChunks_ReasoningThenTextAutoCloseTag(t *testing.T) {
+	state := NewResponsesEventToChatState()
+	state.Model = "gpt-4o"
+	state.SentRole = true
+
+	chunks := ResponsesEventToChatChunks(&ResponsesStreamEvent{
+		Type:  "response.reasoning_summary_text.delta",
+		Delta: "plan",
+	}, state)
+	require.Len(t, chunks, 1)
+	require.NotNil(t, chunks[0].Choices[0].Delta.ReasoningContent)
+	assert.Equal(t, "plan", *chunks[0].Choices[0].Delta.ReasoningContent)
+
+	chunks = ResponsesEventToChatChunks(&ResponsesStreamEvent{
+		Type:  "response.output_text.delta",
+		Delta: "answer",
+	}, state)
+	require.Len(t, chunks, 1)
+	require.NotNil(t, chunks[0].Choices[0].Delta.Content)
+	assert.Equal(t, "answer", *chunks[0].Choices[0].Delta.Content)
+}
+
+func TestFinalizeResponsesChatStream(t *testing.T) {
+	state := NewResponsesEventToChatState()
+	state.Model = "gpt-4o"
+	state.IncludeUsage = true
+	state.Usage = &ChatUsage{
+		PromptTokens:     100,
+		CompletionTokens: 50,
+		TotalTokens:      150,
+	}
+
+	chunks := FinalizeResponsesChatStream(state)
+	require.Len(t, chunks, 2)
+
+	// Finish chunk
+	require.NotNil(t, chunks[0].Choices[0].FinishReason)
+	assert.Equal(t, "stop", *chunks[0].Choices[0].FinishReason)
+
+	// Usage chunk
+	require.NotNil(t, chunks[1].Usage)
+	assert.Equal(t, 100, chunks[1].Usage.PromptTokens)
+
+	// Idempotent: second call returns nil
+	assert.Nil(t, FinalizeResponsesChatStream(state))
+}
+
+func TestFinalizeResponsesChatStream_AfterCompleted(t *testing.T) {
+	// If response.completed already emitted the finish chunk, FinalizeResponsesChatStream
+	// must be a no-op (prevents double finish_reason being sent to the client).
+	state := NewResponsesEventToChatState()
+	state.Model = "gpt-4o"
+	state.IncludeUsage = true
+
+	// Simulate response.completed
+	chunks := ResponsesEventToChatChunks(&ResponsesStreamEvent{
+		Type: "response.completed",
+		Response: &ResponsesResponse{
+			Status: "completed",
+			Usage: &ResponsesUsage{
+				InputTokens:  10,
+				OutputTokens: 5,
+				TotalTokens:  15,
+			},
+		},
+	}, state)
+	require.NotEmpty(t, chunks) // finish + usage chunks
+
+	// Now FinalizeResponsesChatStream should return nil — already finalized.
+	assert.Nil(t, FinalizeResponsesChatStream(state))
+}
+
+func TestChatChunkToSSE(t *testing.T) {
+	chunk := ChatCompletionsChunk{
+		ID:      "chatcmpl-test",
+		Object:  "chat.completion.chunk",
+		Created: 1700000000,
+		Model:   "gpt-4o",
+		Choices: []ChatChunkChoice{
+			{
+				Index:        0,
+				Delta:        ChatDelta{Role: "assistant"},
+				FinishReason: nil,
+			},
+		},
+	}
+
+	sse, err := ChatChunkToSSE(chunk)
+	require.NoError(t, err)
+	assert.Contains(t, sse, "data: ")
+	assert.Contains(t, sse, "chatcmpl-test")
+	assert.Contains(t, sse, "assistant")
+	assert.True(t, len(sse) > 10)
+}
+
+// ---------------------------------------------------------------------------
+// Stream round-trip test
+// ---------------------------------------------------------------------------
+
+func TestChatCompletionsStreamRoundTrip(t *testing.T) {
+	// Simulate: client sends chat completions request, upstream returns Responses SSE events.
+	// Verify that the streaming state machine produces correct chat completions chunks.
+
+	state := NewResponsesEventToChatState()
+	state.Model = "gpt-4o"
+	state.IncludeUsage = true
+
+	var allChunks []ChatCompletionsChunk
+
+	// 1. response.created
+	chunks := ResponsesEventToChatChunks(&ResponsesStreamEvent{
+		Type:     "response.created",
+		Response: &ResponsesResponse{ID: "resp_rt"},
+	}, state)
+	allChunks = append(allChunks, chunks...)
+
+	// 2. text deltas
+	for _, text := range []string{"Hello", ", ", "world", "!"} {
+		chunks = ResponsesEventToChatChunks(&ResponsesStreamEvent{
+			Type:  "response.output_text.delta",
+			Delta: text,
+		}, state)
+		allChunks = append(allChunks, chunks...)
+	}
+
+	// 3. response.completed
+	chunks = ResponsesEventToChatChunks(&ResponsesStreamEvent{
+		Type: "response.completed",
+		Response: &ResponsesResponse{
+			Status: "completed",
+			Usage: &ResponsesUsage{
+				InputTokens:  10,
+				OutputTokens: 4,
+				TotalTokens:  14,
+			},
+		},
+	}, state)
+	allChunks = append(allChunks, chunks...)
+
+	// Verify: role chunk + 4 text chunks + finish chunk + usage chunk = 7
+	require.Len(t, allChunks, 7)
+
+	// First chunk has role
+	assert.Equal(t, "assistant", allChunks[0].Choices[0].Delta.Role)
+
+	// Text chunks
+	var fullText string
+	for i := 1; i <= 4; i++ {
+		require.NotNil(t, allChunks[i].Choices[0].Delta.Content)
+		fullText += *allChunks[i].Choices[0].Delta.Content
+	}
+	assert.Equal(t, "Hello, world!", fullText)
+
+	// Finish chunk
+	require.NotNil(t, allChunks[5].Choices[0].FinishReason)
+	assert.Equal(t, "stop", *allChunks[5].Choices[0].FinishReason)
+
+	// Usage chunk
+	require.NotNil(t, allChunks[6].Usage)
+	assert.Equal(t, 10, allChunks[6].Usage.PromptTokens)
+	assert.Equal(t, 4, allChunks[6].Usage.CompletionTokens)
+
+	// All chunks share the same ID
+	for _, c := range allChunks {
+		assert.Equal(t, "resp_rt", c.ID)
+	}
+}

backend/internal/pkg/apicompat/chatcompletions_to_responses.go

@@ -0,0 +1,385 @@
+package apicompat
+
+import (
+	"encoding/json"
+	"fmt"
+	"strings"
+)
+
+// ChatCompletionsToResponses converts a Chat Completions request into a
+// Responses API request. The upstream always streams, so Stream is forced to
+// true. store is always false and reasoning.encrypted_content is always
+// included so that the response translator has full context.
+func ChatCompletionsToResponses(req *ChatCompletionsRequest) (*ResponsesRequest, error) {
+	input, err := convertChatMessagesToResponsesInput(req.Messages)
+	if err != nil {
+		return nil, err
+	}
+
+	inputJSON, err := json.Marshal(input)
+	if err != nil {
+		return nil, err
+	}
+
+	out := &ResponsesRequest{
+		Model:       req.Model,
+		Input:       inputJSON,
+		Temperature: req.Temperature,
+		TopP:        req.TopP,
+		Stream:      true, // upstream always streams
+		Include:     []string{"reasoning.encrypted_content"},
+		ServiceTier: req.ServiceTier,
+	}
+
+	storeFalse := false
+	out.Store = &storeFalse
+
+	// max_tokens / max_completion_tokens → max_output_tokens, prefer max_completion_tokens
+	maxTokens := 0
+	if req.MaxTokens != nil {
+		maxTokens = *req.MaxTokens
+	}
+	if req.MaxCompletionTokens != nil {
+		maxTokens = *req.MaxCompletionTokens
+	}
+	if maxTokens > 0 {
+		v := maxTokens
+		if v < minMaxOutputTokens {
+			v = minMaxOutputTokens
+		}
+		out.MaxOutputTokens = &v
+	}
+
+	// reasoning_effort → reasoning.effort + reasoning.summary="auto"
+	if req.ReasoningEffort != "" {
+		out.Reasoning = &ResponsesReasoning{
+			Effort:  req.ReasoningEffort,
+			Summary: "auto",
+		}
+	}
+
+	// tools[] and legacy functions[] → ResponsesTool[]
+	if len(req.Tools) > 0 || len(req.Functions) > 0 {
+		out.Tools = convertChatToolsToResponses(req.Tools, req.Functions)
+	}
+
+	// tool_choice: already compatible format — pass through directly.
+	// Legacy function_call needs mapping.
+	if len(req.ToolChoice) > 0 {
+		out.ToolChoice = req.ToolChoice
+	} else if len(req.FunctionCall) > 0 {
+		tc, err := convertChatFunctionCallToToolChoice(req.FunctionCall)
+		if err != nil {
+			return nil, fmt.Errorf("convert function_call: %w", err)
+		}
+		out.ToolChoice = tc
+	}
+
+	return out, nil
+}
+
+// convertChatMessagesToResponsesInput converts the Chat Completions messages
+// array into a Responses API input items array.
+func convertChatMessagesToResponsesInput(msgs []ChatMessage) ([]ResponsesInputItem, error) {
+	var out []ResponsesInputItem
+	for _, m := range msgs {
+		items, err := chatMessageToResponsesItems(m)
+		if err != nil {
+			return nil, err
+		}
+		out = append(out, items...)
+	}
+	return out, nil
+}
+
+// chatMessageToResponsesItems converts a single ChatMessage into one or more
+// ResponsesInputItem values.
+func chatMessageToResponsesItems(m ChatMessage) ([]ResponsesInputItem, error) {
+	switch m.Role {
+	case "system":
+		return chatSystemToResponses(m)
+	case "user":
+		return chatUserToResponses(m)
+	case "assistant":
+		return chatAssistantToResponses(m)
+	case "tool":
+		return chatToolToResponses(m)
+	case "function":
+		return chatFunctionToResponses(m)
+	default:
+		return chatUserToResponses(m)
+	}
+}
+
+// chatSystemToResponses converts a system message.
+func chatSystemToResponses(m ChatMessage) ([]ResponsesInputItem, error) {
+	text, err := parseChatContent(m.Content)
+	if err != nil {
+		return nil, err
+	}
+	content, err := json.Marshal(text)
+	if err != nil {
+		return nil, err
+	}
+	return []ResponsesInputItem{{Role: "system", Content: content}}, nil
+}
+
+// chatUserToResponses converts a user message, handling both plain strings and
+// multi-modal content arrays.
+func chatUserToResponses(m ChatMessage) ([]ResponsesInputItem, error) {
+	// Try plain string first.
+	var s string
+	if err := json.Unmarshal(m.Content, &s); err == nil {
+		content, _ := json.Marshal(s)
+		return []ResponsesInputItem{{Role: "user", Content: content}}, nil
+	}
+
+	var parts []ChatContentPart
+	if err := json.Unmarshal(m.Content, &parts); err != nil {
+		return nil, fmt.Errorf("parse user content: %w", err)
+	}
+
+	var responseParts []ResponsesContentPart
+	for _, p := range parts {
+		switch p.Type {
+		case "text":
+			if p.Text != "" {
+				responseParts = append(responseParts, ResponsesContentPart{
+					Type: "input_text",
+					Text: p.Text,
+				})
+			}
+		case "image_url":
+			if p.ImageURL != nil && p.ImageURL.URL != "" {
+				responseParts = append(responseParts, ResponsesContentPart{
+					Type:     "input_image",
+					ImageURL: p.ImageURL.URL,
+				})
+			}
+		}
+	}
+
+	content, err := json.Marshal(responseParts)
+	if err != nil {
+		return nil, err
+	}
+	return []ResponsesInputItem{{Role: "user", Content: content}}, nil
+}
+
+// chatAssistantToResponses converts an assistant message. If there is both
+// text content and tool_calls, the text is emitted as an assistant message
+// first, then each tool_call becomes a function_call item. If the content is
+// empty/nil and there are tool_calls, only function_call items are emitted.
+func chatAssistantToResponses(m ChatMessage) ([]ResponsesInputItem, error) {
+	var items []ResponsesInputItem
+
+	// Emit assistant message with output_text if content is non-empty.
+	if len(m.Content) > 0 {
+		s, err := parseAssistantContent(m.Content)
+		if err != nil {
+			return nil, err
+		}
+		if s != "" {
+			parts := []ResponsesContentPart{{Type: "output_text", Text: s}}
+			partsJSON, err := json.Marshal(parts)
+			if err != nil {
+				return nil, err
+			}
+			items = append(items, ResponsesInputItem{Role: "assistant", Content: partsJSON})
+		}
+	}
+
+	// Emit one function_call item per tool_call.
+	for _, tc := range m.ToolCalls {
+		args := tc.Function.Arguments
+		if args == "" {
+			args = "{}"
+		}
+		items = append(items, ResponsesInputItem{
+			Type:      "function_call",
+			CallID:    tc.ID,
+			Name:      tc.Function.Name,
+			Arguments: args,
+		})
+	}
+
+	return items, nil
+}
+
+// parseAssistantContent returns assistant content as plain text.
+//
+// Supported formats:
+// - JSON string
+// - JSON array of typed parts (e.g. [{"type":"text","text":"..."}])
+//
+// For structured thinking/reasoning parts, it preserves semantics by wrapping
+// the text in explicit tags so downstream can still distinguish it from normal text.
+func parseAssistantContent(raw json.RawMessage) (string, error) {
+	if len(raw) == 0 {
+		return "", nil
+	}
+
+	var s string
+	if err := json.Unmarshal(raw, &s); err == nil {
+		return s, nil
+	}
+
+	var parts []map[string]any
+	if err := json.Unmarshal(raw, &parts); err != nil {
+		// Keep compatibility with prior behavior: unsupported assistant content
+		// formats are ignored instead of failing the whole request conversion.
+		return "", nil
+	}
+
+	var b strings.Builder
+	write := func(v string) error {
+		_, err := b.WriteString(v)
+		return err
+	}
+	for _, p := range parts {
+		typ, _ := p["type"].(string)
+		text, _ := p["text"].(string)
+		thinking, _ := p["thinking"].(string)
+
+		switch typ {
+		case "thinking", "reasoning":
+			if thinking != "" {
+				if err := write("<thinking>"); err != nil {
+					return "", err
+				}
+				if err := write(thinking); err != nil {
+					return "", err
+				}
+				if err := write("</thinking>"); err != nil {
+					return "", err
+				}
+			} else if text != "" {
+				if err := write("<thinking>"); err != nil {
+					return "", err
+				}
+				if err := write(text); err != nil {
+					return "", err
+				}
+				if err := write("</thinking>"); err != nil {
+					return "", err
+				}
+			}
+		default:
+			if text != "" {
+				if err := write(text); err != nil {
+					return "", err
+				}
+			}
+		}
+	}
+
+	return b.String(), nil
+}
+
+// chatToolToResponses converts a tool result message (role=tool) into a
+// function_call_output item.
+func chatToolToResponses(m ChatMessage) ([]ResponsesInputItem, error) {
+	output, err := parseChatContent(m.Content)
+	if err != nil {
+		return nil, err
+	}
+	if output == "" {
+		output = "(empty)"
+	}
+	return []ResponsesInputItem{{
+		Type:   "function_call_output",
+		CallID: m.ToolCallID,
+		Output: output,
+	}}, nil
+}
+
+// chatFunctionToResponses converts a legacy function result message
+// (role=function) into a function_call_output item. The Name field is used as
+// call_id since legacy function calls do not carry a separate call_id.
+func chatFunctionToResponses(m ChatMessage) ([]ResponsesInputItem, error) {
+	output, err := parseChatContent(m.Content)
+	if err != nil {
+		return nil, err
+	}
+	if output == "" {
+		output = "(empty)"
+	}
+	return []ResponsesInputItem{{
+		Type:   "function_call_output",
+		CallID: m.Name,
+		Output: output,
+	}}, nil
+}
+
+// parseChatContent returns the string value of a ChatMessage Content field.
+// Content must be a JSON string. Returns "" if content is null or empty.
+func parseChatContent(raw json.RawMessage) (string, error) {
+	if len(raw) == 0 {
+		return "", nil
+	}
+	var s string
+	if err := json.Unmarshal(raw, &s); err != nil {
+		return "", fmt.Errorf("parse content as string: %w", err)
+	}
+	return s, nil
+}
+
+// convertChatToolsToResponses maps Chat Completions tool definitions and legacy
+// function definitions to Responses API tool definitions.
+func convertChatToolsToResponses(tools []ChatTool, functions []ChatFunction) []ResponsesTool {
+	var out []ResponsesTool
+
+	for _, t := range tools {
+		if t.Type != "function" || t.Function == nil {
+			continue
+		}
+		rt := ResponsesTool{
+			Type:        "function",
+			Name:        t.Function.Name,
+			Description: t.Function.Description,
+			Parameters:  t.Function.Parameters,
+			Strict:      t.Function.Strict,
+		}
+		out = append(out, rt)
+	}
+
+	// Legacy functions[] are treated as function-type tools.
+	for _, f := range functions {
+		rt := ResponsesTool{
+			Type:        "function",
+			Name:        f.Name,
+			Description: f.Description,
+			Parameters:  f.Parameters,
+			Strict:      f.Strict,
+		}
+		out = append(out, rt)
+	}
+
+	return out
+}
+
+// convertChatFunctionCallToToolChoice maps the legacy function_call field to a
+// Responses API tool_choice value.
+//
+//	"auto" → "auto"
+//	"none" → "none"
+//	{"name":"X"} → {"type":"function","function":{"name":"X"}}
+func convertChatFunctionCallToToolChoice(raw json.RawMessage) (json.RawMessage, error) {
+	// Try string first ("auto", "none", etc.) — pass through as-is.
+	var s string
+	if err := json.Unmarshal(raw, &s); err == nil {
+		return json.Marshal(s)
+	}
+
+	// Object form: {"name":"X"}
+	var obj struct {
+		Name string `json:"name"`
+	}
+	if err := json.Unmarshal(raw, &obj); err != nil {
+		return nil, err
+	}
+	return json.Marshal(map[string]any{
+		"type":     "function",
+		"function": map[string]string{"name": obj.Name},
+	})
+}

backend/internal/pkg/apicompat/responses_to_chatcompletions.go

@@ -0,0 +1,374 @@
+package apicompat
+
+import (
+	"crypto/rand"
+	"encoding/hex"
+	"encoding/json"
+	"fmt"
+	"time"
+)
+
+// ---------------------------------------------------------------------------
+// Non-streaming: ResponsesResponse → ChatCompletionsResponse
+// ---------------------------------------------------------------------------
+
+// ResponsesToChatCompletions converts a Responses API response into a Chat
+// Completions response. Text output items are concatenated into
+// choices[0].message.content; function_call items become tool_calls.
+func ResponsesToChatCompletions(resp *ResponsesResponse, model string) *ChatCompletionsResponse {
+	id := resp.ID
+	if id == "" {
+		id = generateChatCmplID()
+	}
+
+	out := &ChatCompletionsResponse{
+		ID:      id,
+		Object:  "chat.completion",
+		Created: time.Now().Unix(),
+		Model:   model,
+	}
+
+	var contentText string
+	var reasoningText string
+	var toolCalls []ChatToolCall
+
+	for _, item := range resp.Output {
+		switch item.Type {
+		case "message":
+			for _, part := range item.Content {
+				if part.Type == "output_text" && part.Text != "" {
+					contentText += part.Text
+				}
+			}
+		case "function_call":
+			toolCalls = append(toolCalls, ChatToolCall{
+				ID:   item.CallID,
+				Type: "function",
+				Function: ChatFunctionCall{
+					Name:      item.Name,
+					Arguments: item.Arguments,
+				},
+			})
+		case "reasoning":
+			for _, s := range item.Summary {
+				if s.Type == "summary_text" && s.Text != "" {
+					reasoningText += s.Text
+				}
+			}
+		case "web_search_call":
+			// silently consumed — results already incorporated into text output
+		}
+	}
+
+	msg := ChatMessage{Role: "assistant"}
+	if len(toolCalls) > 0 {
+		msg.ToolCalls = toolCalls
+	}
+	if contentText != "" {
+		raw, _ := json.Marshal(contentText)
+		msg.Content = raw
+	}
+	if reasoningText != "" {
+		msg.ReasoningContent = reasoningText
+	}
+
+	finishReason := responsesStatusToChatFinishReason(resp.Status, resp.IncompleteDetails, toolCalls)
+
+	out.Choices = []ChatChoice{{
+		Index:        0,
+		Message:      msg,
+		FinishReason: finishReason,
+	}}
+
+	if resp.Usage != nil {
+		usage := &ChatUsage{
+			PromptTokens:     resp.Usage.InputTokens,
+			CompletionTokens: resp.Usage.OutputTokens,
+			TotalTokens:      resp.Usage.InputTokens + resp.Usage.OutputTokens,
+		}
+		if resp.Usage.InputTokensDetails != nil && resp.Usage.InputTokensDetails.CachedTokens > 0 {
+			usage.PromptTokensDetails = &ChatTokenDetails{
+				CachedTokens: resp.Usage.InputTokensDetails.CachedTokens,
+			}
+		}
+		out.Usage = usage
+	}
+
+	return out
+}
+
+func responsesStatusToChatFinishReason(status string, details *ResponsesIncompleteDetails, toolCalls []ChatToolCall) string {
+	switch status {
+	case "incomplete":
+		if details != nil && details.Reason == "max_output_tokens" {
+			return "length"
+		}
+		return "stop"
+	case "completed":
+		if len(toolCalls) > 0 {
+			return "tool_calls"
+		}
+		return "stop"
+	default:
+		return "stop"
+	}
+}
+
+// ---------------------------------------------------------------------------
+// Streaming: ResponsesStreamEvent → []ChatCompletionsChunk (stateful converter)
+// ---------------------------------------------------------------------------
+
+// ResponsesEventToChatState tracks state for converting a sequence of Responses
+// SSE events into Chat Completions SSE chunks.
+type ResponsesEventToChatState struct {
+	ID                     string
+	Model                  string
+	Created                int64
+	SentRole               bool
+	SawToolCall            bool
+	SawText                bool
+	Finalized              bool        // true after finish chunk has been emitted
+	NextToolCallIndex      int         // next sequential tool_call index to assign
+	OutputIndexToToolIndex map[int]int // Responses output_index → Chat tool_calls index
+	IncludeUsage           bool
+	Usage                  *ChatUsage
+}
+
+// NewResponsesEventToChatState returns an initialised stream state.
+func NewResponsesEventToChatState() *ResponsesEventToChatState {
+	return &ResponsesEventToChatState{
+		ID:                     generateChatCmplID(),
+		Created:                time.Now().Unix(),
+		OutputIndexToToolIndex: make(map[int]int),
+	}
+}
+
+// ResponsesEventToChatChunks converts a single Responses SSE event into zero
+// or more Chat Completions chunks, updating state as it goes.
+func ResponsesEventToChatChunks(evt *ResponsesStreamEvent, state *ResponsesEventToChatState) []ChatCompletionsChunk {
+	switch evt.Type {
+	case "response.created":
+		return resToChatHandleCreated(evt, state)
+	case "response.output_text.delta":
+		return resToChatHandleTextDelta(evt, state)
+	case "response.output_item.added":
+		return resToChatHandleOutputItemAdded(evt, state)
+	case "response.function_call_arguments.delta":
+		return resToChatHandleFuncArgsDelta(evt, state)
+	case "response.reasoning_summary_text.delta":
+		return resToChatHandleReasoningDelta(evt, state)
+	case "response.reasoning_summary_text.done":
+		return nil
+	case "response.completed", "response.incomplete", "response.failed":
+		return resToChatHandleCompleted(evt, state)
+	default:
+		return nil
+	}
+}
+
+// FinalizeResponsesChatStream emits a final chunk with finish_reason if the
+// stream ended without a proper completion event (e.g. upstream disconnect).
+// It is idempotent: if a completion event already emitted the finish chunk,
+// this returns nil.
+func FinalizeResponsesChatStream(state *ResponsesEventToChatState) []ChatCompletionsChunk {
+	if state.Finalized {
+		return nil
+	}
+	state.Finalized = true
+
+	finishReason := "stop"
+	if state.SawToolCall {
+		finishReason = "tool_calls"
+	}
+
+	chunks := []ChatCompletionsChunk{makeChatFinishChunk(state, finishReason)}
+
+	if state.IncludeUsage && state.Usage != nil {
+		chunks = append(chunks, ChatCompletionsChunk{
+			ID:      state.ID,
+			Object:  "chat.completion.chunk",
+			Created: state.Created,
+			Model:   state.Model,
+			Choices: []ChatChunkChoice{},
+			Usage:   state.Usage,
+		})
+	}
+
+	return chunks
+}
+
+// ChatChunkToSSE formats a ChatCompletionsChunk as an SSE data line.
+func ChatChunkToSSE(chunk ChatCompletionsChunk) (string, error) {
+	data, err := json.Marshal(chunk)
+	if err != nil {
+		return "", err
+	}
+	return fmt.Sprintf("data: %s\n\n", data), nil
+}
+
+// --- internal handlers ---
+
+func resToChatHandleCreated(evt *ResponsesStreamEvent, state *ResponsesEventToChatState) []ChatCompletionsChunk {
+	if evt.Response != nil {
+		if evt.Response.ID != "" {
+			state.ID = evt.Response.ID
+		}
+		if state.Model == "" && evt.Response.Model != "" {
+			state.Model = evt.Response.Model
+		}
+	}
+	// Emit the role chunk.
+	if state.SentRole {
+		return nil
+	}
+	state.SentRole = true
+
+	role := "assistant"
+	return []ChatCompletionsChunk{makeChatDeltaChunk(state, ChatDelta{Role: role})}
+}
+
+func resToChatHandleTextDelta(evt *ResponsesStreamEvent, state *ResponsesEventToChatState) []ChatCompletionsChunk {
+	if evt.Delta == "" {
+		return nil
+	}
+	state.SawText = true
+	content := evt.Delta
+	return []ChatCompletionsChunk{makeChatDeltaChunk(state, ChatDelta{Content: &content})}
+}
+
+func resToChatHandleOutputItemAdded(evt *ResponsesStreamEvent, state *ResponsesEventToChatState) []ChatCompletionsChunk {
+	if evt.Item == nil || evt.Item.Type != "function_call" {
+		return nil
+	}
+
+	state.SawToolCall = true
+	idx := state.NextToolCallIndex
+	state.OutputIndexToToolIndex[evt.OutputIndex] = idx
+	state.NextToolCallIndex++
+
+	return []ChatCompletionsChunk{makeChatDeltaChunk(state, ChatDelta{
+		ToolCalls: []ChatToolCall{{
+			Index: &idx,
+			ID:    evt.Item.CallID,
+			Type:  "function",
+			Function: ChatFunctionCall{
+				Name: evt.Item.Name,
+			},
+		}},
+	})}
+}
+
+func resToChatHandleFuncArgsDelta(evt *ResponsesStreamEvent, state *ResponsesEventToChatState) []ChatCompletionsChunk {
+	if evt.Delta == "" {
+		return nil
+	}
+
+	idx, ok := state.OutputIndexToToolIndex[evt.OutputIndex]
+	if !ok {
+		return nil
+	}
+
+	return []ChatCompletionsChunk{makeChatDeltaChunk(state, ChatDelta{
+		ToolCalls: []ChatToolCall{{
+			Index: &idx,
+			Function: ChatFunctionCall{
+				Arguments: evt.Delta,
+			},
+		}},
+	})}
+}
+
+func resToChatHandleReasoningDelta(evt *ResponsesStreamEvent, state *ResponsesEventToChatState) []ChatCompletionsChunk {
+	if evt.Delta == "" {
+		return nil
+	}
+	reasoning := evt.Delta
+	return []ChatCompletionsChunk{makeChatDeltaChunk(state, ChatDelta{ReasoningContent: &reasoning})}
+}
+
+func resToChatHandleCompleted(evt *ResponsesStreamEvent, state *ResponsesEventToChatState) []ChatCompletionsChunk {
+	state.Finalized = true
+	finishReason := "stop"
+
+	if evt.Response != nil {
+		if evt.Response.Usage != nil {
+			u := evt.Response.Usage
+			usage := &ChatUsage{
+				PromptTokens:     u.InputTokens,
+				CompletionTokens: u.OutputTokens,
+				TotalTokens:      u.InputTokens + u.OutputTokens,
+			}
+			if u.InputTokensDetails != nil && u.InputTokensDetails.CachedTokens > 0 {
+				usage.PromptTokensDetails = &ChatTokenDetails{
+					CachedTokens: u.InputTokensDetails.CachedTokens,
+				}
+			}
+			state.Usage = usage
+		}
+
+		switch evt.Response.Status {
+		case "incomplete":
+			if evt.Response.IncompleteDetails != nil && evt.Response.IncompleteDetails.Reason == "max_output_tokens" {
+				finishReason = "length"
+			}
+		case "completed":
+			if state.SawToolCall {
+				finishReason = "tool_calls"
+			}
+		}
+	} else if state.SawToolCall {
+		finishReason = "tool_calls"
+	}
+
+	var chunks []ChatCompletionsChunk
+	chunks = append(chunks, makeChatFinishChunk(state, finishReason))
+
+	if state.IncludeUsage && state.Usage != nil {
+		chunks = append(chunks, ChatCompletionsChunk{
+			ID:      state.ID,
+			Object:  "chat.completion.chunk",
+			Created: state.Created,
+			Model:   state.Model,
+			Choices: []ChatChunkChoice{},
+			Usage:   state.Usage,
+		})
+	}
+
+	return chunks
+}
+
+func makeChatDeltaChunk(state *ResponsesEventToChatState, delta ChatDelta) ChatCompletionsChunk {
+	return ChatCompletionsChunk{
+		ID:      state.ID,
+		Object:  "chat.completion.chunk",
+		Created: state.Created,
+		Model:   state.Model,
+		Choices: []ChatChunkChoice{{
+			Index:        0,
+			Delta:        delta,
+			FinishReason: nil,
+		}},
+	}
+}
+
+func makeChatFinishChunk(state *ResponsesEventToChatState, finishReason string) ChatCompletionsChunk {
+	empty := ""
+	return ChatCompletionsChunk{
+		ID:      state.ID,
+		Object:  "chat.completion.chunk",
+		Created: state.Created,
+		Model:   state.Model,
+		Choices: []ChatChunkChoice{{
+			Index:        0,
+			Delta:        ChatDelta{Content: &empty},
+			FinishReason: &finishReason,
+		}},
+	}
+}
+
+// generateChatCmplID returns a "chatcmpl-" prefixed random hex ID.
+func generateChatCmplID() string {
+	b := make([]byte, 12)
+	_, _ = rand.Read(b)
+	return "chatcmpl-" + hex.EncodeToString(b)
+}

backend/internal/pkg/apicompat/types.go

@@ -329,6 +329,150 @@ type ResponsesStreamEvent struct {
 	SequenceNumber int `json:"sequence_number,omitempty"`
 }
 
+// ---------------------------------------------------------------------------
+// OpenAI Chat Completions API types
+// ---------------------------------------------------------------------------
+
+// ChatCompletionsRequest is the request body for POST /v1/chat/completions.
+type ChatCompletionsRequest struct {
+	Model               string             `json:"model"`
+	Messages            []ChatMessage      `json:"messages"`
+	MaxTokens           *int               `json:"max_tokens,omitempty"`
+	MaxCompletionTokens *int               `json:"max_completion_tokens,omitempty"`
+	Temperature         *float64           `json:"temperature,omitempty"`
+	TopP                *float64           `json:"top_p,omitempty"`
+	Stream              bool               `json:"stream,omitempty"`
+	StreamOptions       *ChatStreamOptions `json:"stream_options,omitempty"`
+	Tools               []ChatTool         `json:"tools,omitempty"`
+	ToolChoice          json.RawMessage    `json:"tool_choice,omitempty"`
+	ReasoningEffort     string             `json:"reasoning_effort,omitempty"` // "low" | "medium" | "high"
+	ServiceTier         string             `json:"service_tier,omitempty"`
+	Stop                json.RawMessage    `json:"stop,omitempty"` // string or []string
+
+	// Legacy function calling (deprecated but still supported)
+	Functions    []ChatFunction  `json:"functions,omitempty"`
+	FunctionCall json.RawMessage `json:"function_call,omitempty"`
+}
+
+// ChatStreamOptions configures streaming behavior.
+type ChatStreamOptions struct {
+	IncludeUsage bool `json:"include_usage,omitempty"`
+}
+
+// ChatMessage is a single message in the Chat Completions conversation.
+type ChatMessage struct {
+	Role             string          `json:"role"` // "system" | "user" | "assistant" | "tool" | "function"
+	Content          json.RawMessage `json:"content,omitempty"`
+	ReasoningContent string          `json:"reasoning_content,omitempty"`
+	Name             string          `json:"name,omitempty"`
+	ToolCalls        []ChatToolCall  `json:"tool_calls,omitempty"`
+	ToolCallID       string          `json:"tool_call_id,omitempty"`
+
+	// Legacy function calling
+	FunctionCall *ChatFunctionCall `json:"function_call,omitempty"`
+}
+
+// ChatContentPart is a typed content part in a multi-modal message.
+type ChatContentPart struct {
+	Type     string        `json:"type"` // "text" | "image_url"
+	Text     string        `json:"text,omitempty"`
+	ImageURL *ChatImageURL `json:"image_url,omitempty"`
+}
+
+// ChatImageURL contains the URL for an image content part.
+type ChatImageURL struct {
+	URL    string `json:"url"`
+	Detail string `json:"detail,omitempty"` // "auto" | "low" | "high"
+}
+
+// ChatTool describes a tool available to the model.
+type ChatTool struct {
+	Type     string        `json:"type"` // "function"
+	Function *ChatFunction `json:"function,omitempty"`
+}
+
+// ChatFunction describes a function tool definition.
+type ChatFunction struct {
+	Name        string          `json:"name"`
+	Description string          `json:"description,omitempty"`
+	Parameters  json.RawMessage `json:"parameters,omitempty"`
+	Strict      *bool           `json:"strict,omitempty"`
+}
+
+// ChatToolCall represents a tool call made by the assistant.
+// Index is only populated in streaming chunks (omitted in non-streaming responses).
+type ChatToolCall struct {
+	Index    *int             `json:"index,omitempty"`
+	ID       string           `json:"id,omitempty"`
+	Type     string           `json:"type,omitempty"` // "function"
+	Function ChatFunctionCall `json:"function"`
+}
+
+// ChatFunctionCall contains the function name and arguments.
+type ChatFunctionCall struct {
+	Name      string `json:"name"`
+	Arguments string `json:"arguments"`
+}
+
+// ChatCompletionsResponse is the non-streaming response from POST /v1/chat/completions.
+type ChatCompletionsResponse struct {
+	ID                string       `json:"id"`
+	Object            string       `json:"object"` // "chat.completion"
+	Created           int64        `json:"created"`
+	Model             string       `json:"model"`
+	Choices           []ChatChoice `json:"choices"`
+	Usage             *ChatUsage   `json:"usage,omitempty"`
+	SystemFingerprint string       `json:"system_fingerprint,omitempty"`
+	ServiceTier       string       `json:"service_tier,omitempty"`
+}
+
+// ChatChoice is a single completion choice.
+type ChatChoice struct {
+	Index        int         `json:"index"`
+	Message      ChatMessage `json:"message"`
+	FinishReason string      `json:"finish_reason"` // "stop" | "length" | "tool_calls" | "content_filter"
+}
+
+// ChatUsage holds token counts in Chat Completions format.
+type ChatUsage struct {
+	PromptTokens        int               `json:"prompt_tokens"`
+	CompletionTokens    int               `json:"completion_tokens"`
+	TotalTokens         int               `json:"total_tokens"`
+	PromptTokensDetails *ChatTokenDetails `json:"prompt_tokens_details,omitempty"`
+}
+
+// ChatTokenDetails provides a breakdown of token usage.
+type ChatTokenDetails struct {
+	CachedTokens int `json:"cached_tokens,omitempty"`
+}
+
+// ChatCompletionsChunk is a single streaming chunk from POST /v1/chat/completions.
+type ChatCompletionsChunk struct {
+	ID                string            `json:"id"`
+	Object            string            `json:"object"` // "chat.completion.chunk"
+	Created           int64             `json:"created"`
+	Model             string            `json:"model"`
+	Choices           []ChatChunkChoice `json:"choices"`
+	Usage             *ChatUsage        `json:"usage,omitempty"`
+	SystemFingerprint string            `json:"system_fingerprint,omitempty"`
+	ServiceTier       string            `json:"service_tier,omitempty"`
+}
+
+// ChatChunkChoice is a single choice in a streaming chunk.
+type ChatChunkChoice struct {
+	Index        int       `json:"index"`
+	Delta        ChatDelta `json:"delta"`
+	FinishReason *string   `json:"finish_reason"` // pointer: null when not final
+}
+
+// ChatDelta carries incremental content in a streaming chunk.
+type ChatDelta struct {
+	Role             string         `json:"role,omitempty"`
+	Content          *string        `json:"content,omitempty"` // pointer: omit when not present, null vs "" matters
+	ReasoningContent *string        `json:"reasoning_content,omitempty"`
+	ToolCalls        []ChatToolCall `json:"tool_calls,omitempty"`
+}
+
 // ---------------------------------------------------------------------------
 // Shared constants
 // ---------------------------------------------------------------------------

backend/internal/pkg/gemini/models.go

@@ -18,10 +18,12 @@ func DefaultModels() []Model {
 	return []Model{
 		{Name: "models/gemini-2.0-flash", SupportedGenerationMethods: methods},
 		{Name: "models/gemini-2.5-flash", SupportedGenerationMethods: methods},
+		{Name: "models/gemini-2.5-flash-image", SupportedGenerationMethods: methods},
 		{Name: "models/gemini-2.5-pro", SupportedGenerationMethods: methods},
 		{Name: "models/gemini-3-flash-preview", SupportedGenerationMethods: methods},
 		{Name: "models/gemini-3-pro-preview", SupportedGenerationMethods: methods},
 		{Name: "models/gemini-3.1-pro-preview", SupportedGenerationMethods: methods},
+		{Name: "models/gemini-3.1-flash-image", SupportedGenerationMethods: methods},
 	}
 }
 

backend/internal/pkg/gemini/models_test.go

@@ -0,0 +1,28 @@
+package gemini
+
+import "testing"
+
+func TestDefaultModels_ContainsImageModels(t *testing.T) {
+	t.Parallel()
+
+	models := DefaultModels()
+	byName := make(map[string]Model, len(models))
+	for _, model := range models {
+		byName[model.Name] = model
+	}
+
+	required := []string{
+		"models/gemini-2.5-flash-image",
+		"models/gemini-3.1-flash-image",
+	}
+
+	for _, name := range required {
+		model, ok := byName[name]
+		if !ok {
+			t.Fatalf("expected fallback model %q to exist", name)
+		}
+		if len(model.SupportedGenerationMethods) == 0 {
+			t.Fatalf("expected fallback model %q to advertise generation methods", name)
+		}
+	}
+}

backend/internal/pkg/geminicli/models.go

@@ -13,10 +13,12 @@ type Model struct {
 var DefaultModels = []Model{
 	{ID: "gemini-2.0-flash", Type: "model", DisplayName: "Gemini 2.0 Flash", CreatedAt: ""},
 	{ID: "gemini-2.5-flash", Type: "model", DisplayName: "Gemini 2.5 Flash", CreatedAt: ""},
+	{ID: "gemini-2.5-flash-image", Type: "model", DisplayName: "Gemini 2.5 Flash Image", CreatedAt: ""},
 	{ID: "gemini-2.5-pro", Type: "model", DisplayName: "Gemini 2.5 Pro", CreatedAt: ""},
 	{ID: "gemini-3-flash-preview", Type: "model", DisplayName: "Gemini 3 Flash Preview", CreatedAt: ""},
 	{ID: "gemini-3-pro-preview", Type: "model", DisplayName: "Gemini 3 Pro Preview", CreatedAt: ""},
 	{ID: "gemini-3.1-pro-preview", Type: "model", DisplayName: "Gemini 3.1 Pro Preview", CreatedAt: ""},
+	{ID: "gemini-3.1-flash-image", Type: "model", DisplayName: "Gemini 3.1 Flash Image", CreatedAt: ""},
 }
 
 // DefaultTestModel is the default model to preselect in test flows.

backend/internal/pkg/geminicli/models_test.go

@@ -0,0 +1,23 @@
+package geminicli
+
+import "testing"
+
+func TestDefaultModels_ContainsImageModels(t *testing.T) {
+	t.Parallel()
+
+	byID := make(map[string]Model, len(DefaultModels))
+	for _, model := range DefaultModels {
+		byID[model.ID] = model
+	}
+
+	required := []string{
+		"gemini-2.5-flash-image",
+		"gemini-3.1-flash-image",
+	}
+
+	for _, id := range required {
+		if _, ok := byID[id]; !ok {
+			t.Fatalf("expected curated Gemini model %q to exist", id)
+		}
+	}
+}

backend/internal/pkg/response/response.go

@@ -47,6 +47,15 @@ func Created(c *gin.Context, data any) {
 	})
 }
 
+// Accepted 返回异步接受响应 (HTTP 202)
+func Accepted(c *gin.Context, data any) {
+	c.JSON(http.StatusAccepted, Response{
+		Code:    0,
+		Message: "accepted",
+		Data:    data,
+	})
+}
+
 // Error 返回错误响应
 func Error(c *gin.Context, statusCode int, message string) {
 	c.JSON(statusCode, Response{

backend/internal/pkg/usagestats/usage_log_types.go

@@ -3,6 +3,28 @@ package usagestats
 
 import "time"
 
+const (
+	ModelSourceRequested = "requested"
+	ModelSourceUpstream  = "upstream"
+	ModelSourceMapping   = "mapping"
+)
+
+func IsValidModelSource(source string) bool {
+	switch source {
+	case ModelSourceRequested, ModelSourceUpstream, ModelSourceMapping:
+		return true
+	default:
+		return false
+	}
+}
+
+func NormalizeModelSource(source string) string {
+	if IsValidModelSource(source) {
+		return source
+	}
+	return ModelSourceRequested
+}
+
 // DashboardStats 仪表盘统计
 type DashboardStats struct {
 	// 用户统计
@@ -81,6 +103,22 @@ type ModelStat struct {
 	ActualCost          float64 `json:"actual_cost"` // 实际扣除
 }
 
+// EndpointStat represents usage statistics for a single request endpoint.
+type EndpointStat struct {
+	Endpoint    string  `json:"endpoint"`
+	Requests    int64   `json:"requests"`
+	TotalTokens int64   `json:"total_tokens"`
+	Cost        float64 `json:"cost"`        // 标准计费
+	ActualCost  float64 `json:"actual_cost"` // 实际扣除
+}
+
+// GroupUsageSummary represents today's and cumulative cost for a single group.
+type GroupUsageSummary struct {
+	GroupID   int64   `json:"group_id"`
+	TodayCost float64 `json:"today_cost"`
+	TotalCost float64 `json:"total_cost"`
+}
+
 // GroupStat represents usage statistics for a single group
 type GroupStat struct {
 	GroupID     int64   `json:"group_id"`
@@ -96,12 +134,49 @@ type UserUsageTrendPoint struct {
 	Date       string  `json:"date"`
 	UserID     int64   `json:"user_id"`
 	Email      string  `json:"email"`
+	Username   string  `json:"username"`
 	Requests   int64   `json:"requests"`
 	Tokens     int64   `json:"tokens"`
 	Cost       float64 `json:"cost"`        // 标准计费
 	ActualCost float64 `json:"actual_cost"` // 实际扣除
 }
 
+// UserSpendingRankingItem represents a user spending ranking row.
+type UserSpendingRankingItem struct {
+	UserID     int64   `json:"user_id"`
+	Email      string  `json:"email"`
+	ActualCost float64 `json:"actual_cost"` // 实际扣除
+	Requests   int64   `json:"requests"`
+	Tokens     int64   `json:"tokens"`
+}
+
+// UserSpendingRankingResponse represents ranking rows plus total spend for the time range.
+type UserSpendingRankingResponse struct {
+	Ranking         []UserSpendingRankingItem `json:"ranking"`
+	TotalActualCost float64                   `json:"total_actual_cost"`
+	TotalRequests   int64                     `json:"total_requests"`
+	TotalTokens     int64                     `json:"total_tokens"`
+}
+
+// UserBreakdownItem represents per-user usage breakdown within a dimension (group, model, endpoint).
+type UserBreakdownItem struct {
+	UserID      int64   `json:"user_id"`
+	Email       string  `json:"email"`
+	Requests    int64   `json:"requests"`
+	TotalTokens int64   `json:"total_tokens"`
+	Cost        float64 `json:"cost"`        // 标准计费
+	ActualCost  float64 `json:"actual_cost"` // 实际扣除
+}
+
+// UserBreakdownDimension specifies the dimension to filter for user breakdown.
+type UserBreakdownDimension struct {
+	GroupID      int64  // filter by group_id (>0 to enable)
+	Model        string // filter by model name (non-empty to enable)
+	ModelType    string // "requested", "upstream", or "mapping"
+	Endpoint     string // filter by endpoint value (non-empty to enable)
+	EndpointType string // "inbound", "upstream", or "path"
+}
+
 // APIKeyUsageTrendPoint represents API key usage trend data point
 type APIKeyUsageTrendPoint struct {
 	Date     string `json:"date"`
@@ -163,15 +238,18 @@ type UsageLogFilters struct {
 
 // UsageStats represents usage statistics
 type UsageStats struct {
-	TotalRequests     int64    `json:"total_requests"`
-	TotalInputTokens  int64    `json:"total_input_tokens"`
-	TotalOutputTokens int64    `json:"total_output_tokens"`
-	TotalCacheTokens  int64    `json:"total_cache_tokens"`
-	TotalTokens       int64    `json:"total_tokens"`
-	TotalCost         float64  `json:"total_cost"`
-	TotalActualCost   float64  `json:"total_actual_cost"`
-	TotalAccountCost  *float64 `json:"total_account_cost,omitempty"`
-	AverageDurationMs float64  `json:"average_duration_ms"`
+	TotalRequests     int64          `json:"total_requests"`
+	TotalInputTokens  int64          `json:"total_input_tokens"`
+	TotalOutputTokens int64          `json:"total_output_tokens"`
+	TotalCacheTokens  int64          `json:"total_cache_tokens"`
+	TotalTokens       int64          `json:"total_tokens"`
+	TotalCost         float64        `json:"total_cost"`
+	TotalActualCost   float64        `json:"total_actual_cost"`
+	TotalAccountCost  *float64       `json:"total_account_cost,omitempty"`
+	AverageDurationMs float64        `json:"average_duration_ms"`
+	Endpoints         []EndpointStat `json:"endpoints,omitempty"`
+	UpstreamEndpoints []EndpointStat `json:"upstream_endpoints,omitempty"`
+	EndpointPaths     []EndpointStat `json:"endpoint_paths,omitempty"`
 }
 
 // BatchUserUsageStats represents usage stats for a single user
@@ -238,7 +316,9 @@ type AccountUsageSummary struct {
 
 // AccountUsageStatsResponse represents the full usage statistics response for an account
 type AccountUsageStatsResponse struct {
-	History []AccountUsageHistory `json:"history"`
-	Summary AccountUsageSummary   `json:"summary"`
-	Models  []ModelStat           `json:"models"`
+	History           []AccountUsageHistory `json:"history"`
+	Summary           AccountUsageSummary   `json:"summary"`
+	Models            []ModelStat           `json:"models"`
+	Endpoints         []EndpointStat        `json:"endpoints"`
+	UpstreamEndpoints []EndpointStat        `json:"upstream_endpoints"`
 }

backend/internal/pkg/usagestats/usage_log_types_test.go

@@ -0,0 +1,47 @@
+package usagestats
+
+import "testing"
+
+func TestIsValidModelSource(t *testing.T) {
+	tests := []struct {
+		name   string
+		source string
+		want   bool
+	}{
+		{name: "requested", source: ModelSourceRequested, want: true},
+		{name: "upstream", source: ModelSourceUpstream, want: true},
+		{name: "mapping", source: ModelSourceMapping, want: true},
+		{name: "invalid", source: "foobar", want: false},
+		{name: "empty", source: "", want: false},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			if got := IsValidModelSource(tc.source); got != tc.want {
+				t.Fatalf("IsValidModelSource(%q)=%v want %v", tc.source, got, tc.want)
+			}
+		})
+	}
+}
+
+func TestNormalizeModelSource(t *testing.T) {
+	tests := []struct {
+		name   string
+		source string
+		want   string
+	}{
+		{name: "requested", source: ModelSourceRequested, want: ModelSourceRequested},
+		{name: "upstream", source: ModelSourceUpstream, want: ModelSourceUpstream},
+		{name: "mapping", source: ModelSourceMapping, want: ModelSourceMapping},
+		{name: "invalid falls back", source: "foobar", want: ModelSourceRequested},
+		{name: "empty falls back", source: "", want: ModelSourceRequested},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			if got := NormalizeModelSource(tc.source); got != tc.want {
+				t.Fatalf("NormalizeModelSource(%q)=%q want %q", tc.source, got, tc.want)
+			}
+		})
+	}
+}

backend/internal/repository/account_repo.go

@@ -16,6 +16,7 @@ import (
 	"encoding/json"
 	"errors"
 	"strconv"
+	"strings"
 	"time"
 
 	dbent "github.com/Wei-Shaw/sub2api/ent"
@@ -50,6 +51,19 @@ type accountRepository struct {
 	schedulerCache service.SchedulerCache
 }
 
+var schedulerNeutralExtraKeyPrefixes = []string{
+	"codex_primary_",
+	"codex_secondary_",
+	"codex_5h_",
+	"codex_7d_",
+	"passive_usage_",
+}
+
+var schedulerNeutralExtraKeys = map[string]struct{}{
+	"codex_usage_updated_at":     {},
+	"session_window_utilization": {},
+}
+
 // NewAccountRepository 创建账户仓储实例。
 // 这是对外暴露的构造函数，返回接口类型以便于依赖注入。
 func NewAccountRepository(client *dbent.Client, sqlDB *sql.DB, schedulerCache service.SchedulerCache) service.AccountRepository {
@@ -384,9 +398,9 @@ func (r *accountRepository) Update(ctx context.Context, account *service.Account
 	if err := enqueueSchedulerOutbox(ctx, r.sql, service.SchedulerOutboxEventAccountChanged, &account.ID, nil, buildSchedulerGroupPayload(account.GroupIDs)); err != nil {
 		logger.LegacyPrintf("repository.account", "[SchedulerOutbox] enqueue account update failed: account=%d err=%v", account.ID, err)
 	}
-	if account.Status == service.StatusError || account.Status == service.StatusDisabled || !account.Schedulable {
-		r.syncSchedulerAccountSnapshot(ctx, account.ID)
-	}
+	// 普通账号编辑（如 model_mapping / credentials）也需要立即刷新单账号快照，
+	// 否则网关在 outbox worker 延迟或异常时仍可能读到旧配置。
+	r.syncSchedulerAccountSnapshot(ctx, account.ID)
 	return nil
 }
 
@@ -460,7 +474,9 @@ func (r *accountRepository) ListWithFilters(ctx context.Context, params paginati
 	if search != "" {
 		q = q.Where(dbaccount.NameContainsFold(search))
 	}
-	if groupID > 0 {
+	if groupID == service.AccountListGroupUngrouped {
+		q = q.Where(dbaccount.Not(dbaccount.HasAccountGroups()))
+	} else if groupID > 0 {
 		q = q.Where(dbaccount.HasAccountGroupsWith(dbaccountgroup.GroupIDEQ(groupID)))
 	}
 
@@ -1185,12 +1201,48 @@ func (r *accountRepository) UpdateExtra(ctx context.Context, id int64, updates m
 	if affected == 0 {
 		return service.ErrAccountNotFound
 	}
-	if err := enqueueSchedulerOutbox(ctx, r.sql, service.SchedulerOutboxEventAccountChanged, &id, nil, nil); err != nil {
-		logger.LegacyPrintf("repository.account", "[SchedulerOutbox] enqueue extra update failed: account=%d err=%v", id, err)
+	if shouldEnqueueSchedulerOutboxForExtraUpdates(updates) {
+		if err := enqueueSchedulerOutbox(ctx, r.sql, service.SchedulerOutboxEventAccountChanged, &id, nil, nil); err != nil {
+			logger.LegacyPrintf("repository.account", "[SchedulerOutbox] enqueue extra update failed: account=%d err=%v", id, err)
+		}
+	} else {
+		// 观测型 extra 字段不需要触发 bucket 重建，但仍同步单账号快照，
+		// 让 sticky session / GetAccount 命中缓存时也能读到最新数据，
+		// 同时避免缓存局部 patch 覆盖掉并发写入的其它账号字段。
+		r.syncSchedulerAccountSnapshot(ctx, id)
 	}
 	return nil
 }
 
+func shouldEnqueueSchedulerOutboxForExtraUpdates(updates map[string]any) bool {
+	if len(updates) == 0 {
+		return false
+	}
+	for key := range updates {
+		if isSchedulerNeutralExtraKey(key) {
+			continue
+		}
+		return true
+	}
+	return false
+}
+
+func isSchedulerNeutralExtraKey(key string) bool {
+	key = strings.TrimSpace(key)
+	if key == "" {
+		return false
+	}
+	if _, ok := schedulerNeutralExtraKeys[key]; ok {
+		return true
+	}
+	for _, prefix := range schedulerNeutralExtraKeyPrefixes {
+		if strings.HasPrefix(key, prefix) {
+			return true
+		}
+	}
+	return false
+}
+
 func (r *accountRepository) BulkUpdate(ctx context.Context, ids []int64, updates service.AccountBulkUpdate) (int64, error) {
 	if len(ids) == 0 {
 		return 0, nil
@@ -1678,8 +1730,96 @@ func (r *accountRepository) FindByExtraField(ctx context.Context, key string, va
 // nowUTC is a SQL expression to generate a UTC RFC3339 timestamp string.
 const nowUTC = `to_char(NOW() AT TIME ZONE 'UTC', 'YYYY-MM-DD"T"HH24:MI:SS.US"Z"')`
 
+// dailyExpiredExpr is a SQL expression that evaluates to TRUE when daily quota period has expired.
+// Supports both rolling (24h from start) and fixed (pre-computed reset_at) modes.
+const dailyExpiredExpr = `(
+	CASE WHEN COALESCE(extra->>'quota_daily_reset_mode', 'rolling') = 'fixed'
+	THEN NOW() >= COALESCE((extra->>'quota_daily_reset_at')::timestamptz, '1970-01-01'::timestamptz)
+	ELSE COALESCE((extra->>'quota_daily_start')::timestamptz, '1970-01-01'::timestamptz)
+		+ '24 hours'::interval <= NOW()
+	END
+)`
+
+// weeklyExpiredExpr is a SQL expression that evaluates to TRUE when weekly quota period has expired.
+const weeklyExpiredExpr = `(
+	CASE WHEN COALESCE(extra->>'quota_weekly_reset_mode', 'rolling') = 'fixed'
+	THEN NOW() >= COALESCE((extra->>'quota_weekly_reset_at')::timestamptz, '1970-01-01'::timestamptz)
+	ELSE COALESCE((extra->>'quota_weekly_start')::timestamptz, '1970-01-01'::timestamptz)
+		+ '168 hours'::interval <= NOW()
+	END
+)`
+
+// nextDailyResetAtExpr is a SQL expression to compute the next daily reset_at when a reset occurs.
+// For fixed mode: computes the next future reset time based on NOW(), timezone, and configured hour.
+// This correctly handles long-inactive accounts by jumping directly to the next valid reset point.
+const nextDailyResetAtExpr = `(
+	CASE WHEN COALESCE(extra->>'quota_daily_reset_mode', 'rolling') = 'fixed'
+	THEN to_char((
+		-- Compute today's reset point in the configured timezone, then pick next future one
+		CASE WHEN NOW() >= (
+			date_trunc('day', NOW() AT TIME ZONE COALESCE(extra->>'quota_reset_timezone', 'UTC'))
+			+ (COALESCE((extra->>'quota_daily_reset_hour')::int, 0) || ' hours')::interval
+		) AT TIME ZONE COALESCE(extra->>'quota_reset_timezone', 'UTC')
+		-- NOW() is at or past today's reset point → next reset is tomorrow
+		THEN (
+			date_trunc('day', NOW() AT TIME ZONE COALESCE(extra->>'quota_reset_timezone', 'UTC'))
+			+ (COALESCE((extra->>'quota_daily_reset_hour')::int, 0) || ' hours')::interval
+			+ '1 day'::interval
+		) AT TIME ZONE COALESCE(extra->>'quota_reset_timezone', 'UTC')
+		-- NOW() is before today's reset point → next reset is today
+		ELSE (
+			date_trunc('day', NOW() AT TIME ZONE COALESCE(extra->>'quota_reset_timezone', 'UTC'))
+			+ (COALESCE((extra->>'quota_daily_reset_hour')::int, 0) || ' hours')::interval
+		) AT TIME ZONE COALESCE(extra->>'quota_reset_timezone', 'UTC')
+		END
+	) AT TIME ZONE 'UTC', 'YYYY-MM-DD"T"HH24:MI:SS"Z"')
+	ELSE NULL END
+)`
+
+// nextWeeklyResetAtExpr is a SQL expression to compute the next weekly reset_at when a reset occurs.
+// For fixed mode: computes the next future reset time based on NOW(), timezone, configured day and hour.
+// This correctly handles long-inactive accounts by jumping directly to the next valid reset point.
+const nextWeeklyResetAtExpr = `(
+	CASE WHEN COALESCE(extra->>'quota_weekly_reset_mode', 'rolling') = 'fixed'
+	THEN to_char((
+		-- Compute this week's reset point in the configured timezone
+		-- Step 1: get today's date at reset hour in configured tz
+		-- Step 2: compute days forward to target weekday
+		-- Step 3: if same day but past reset hour, advance 7 days
+		CASE
+		WHEN (
+			-- days_forward = (target_day - current_day + 7) % 7
+			(COALESCE((extra->>'quota_weekly_reset_day')::int, 1)
+			 - EXTRACT(DOW FROM NOW() AT TIME ZONE COALESCE(extra->>'quota_reset_timezone', 'UTC'))::int
+			 + 7) % 7
+		) = 0 AND NOW() >= (
+			date_trunc('day', NOW() AT TIME ZONE COALESCE(extra->>'quota_reset_timezone', 'UTC'))
+			+ (COALESCE((extra->>'quota_weekly_reset_hour')::int, 0) || ' hours')::interval
+		) AT TIME ZONE COALESCE(extra->>'quota_reset_timezone', 'UTC')
+		-- Same weekday and past reset hour → next week
+		THEN (
+			date_trunc('day', NOW() AT TIME ZONE COALESCE(extra->>'quota_reset_timezone', 'UTC'))
+			+ (COALESCE((extra->>'quota_weekly_reset_hour')::int, 0) || ' hours')::interval
+			+ '7 days'::interval
+		) AT TIME ZONE COALESCE(extra->>'quota_reset_timezone', 'UTC')
+		ELSE (
+			-- Advance to target weekday this week (or next if days_forward > 0)
+			date_trunc('day', NOW() AT TIME ZONE COALESCE(extra->>'quota_reset_timezone', 'UTC'))
+			+ (COALESCE((extra->>'quota_weekly_reset_hour')::int, 0) || ' hours')::interval
+			+ ((
+				(COALESCE((extra->>'quota_weekly_reset_day')::int, 1)
+				 - EXTRACT(DOW FROM NOW() AT TIME ZONE COALESCE(extra->>'quota_reset_timezone', 'UTC'))::int
+				 + 7) % 7
+			) || ' days')::interval
+		) AT TIME ZONE COALESCE(extra->>'quota_reset_timezone', 'UTC')
+		END
+	) AT TIME ZONE 'UTC', 'YYYY-MM-DD"T"HH24:MI:SS"Z"')
+	ELSE NULL END
+)`
+
 // IncrementQuotaUsed 原子递增账号的配额用量（总/日/周三个维度）
 // 日/周额度在周期过期时自动重置为 0 再递增。
+// 支持滚动窗口（rolling）和固定时间（fixed）两种重置模式。
 func (r *accountRepository) IncrementQuotaUsed(ctx context.Context, id int64, amount float64) error {
 	rows, err := r.sql.QueryContext(ctx,
 		`UPDATE accounts SET extra = (
@@ -1690,31 +1830,35 @@ func (r *accountRepository) IncrementQuotaUsed(ctx context.Context, id int64, am
 			|| CASE WHEN COALESCE((extra->>'quota_daily_limit')::numeric, 0) > 0 THEN
 				jsonb_build_object(
 					'quota_daily_used',
-					CASE WHEN COALESCE((extra->>'quota_daily_start')::timestamptz, '1970-01-01'::timestamptz)
-						+ '24 hours'::interval <= NOW()
+					CASE WHEN `+dailyExpiredExpr+`
 					THEN $1
 					ELSE COALESCE((extra->>'quota_daily_used')::numeric, 0) + $1 END,
 					'quota_daily_start',
-					CASE WHEN COALESCE((extra->>'quota_daily_start')::timestamptz, '1970-01-01'::timestamptz)
-						+ '24 hours'::interval <= NOW()
+					CASE WHEN `+dailyExpiredExpr+`
 					THEN `+nowUTC+`
 					ELSE COALESCE(extra->>'quota_daily_start', `+nowUTC+`) END
 				)
+				-- 固定模式重置时更新下次重置时间
+				|| CASE WHEN `+dailyExpiredExpr+` AND `+nextDailyResetAtExpr+` IS NOT NULL
+				   THEN jsonb_build_object('quota_daily_reset_at', `+nextDailyResetAtExpr+`)
+				   ELSE '{}'::jsonb END
 			ELSE '{}'::jsonb END
 			-- 周额度：仅在 quota_weekly_limit > 0 时处理
 			|| CASE WHEN COALESCE((extra->>'quota_weekly_limit')::numeric, 0) > 0 THEN
 				jsonb_build_object(
 					'quota_weekly_used',
-					CASE WHEN COALESCE((extra->>'quota_weekly_start')::timestamptz, '1970-01-01'::timestamptz)
-						+ '168 hours'::interval <= NOW()
+					CASE WHEN `+weeklyExpiredExpr+`
 					THEN $1
 					ELSE COALESCE((extra->>'quota_weekly_used')::numeric, 0) + $1 END,
 					'quota_weekly_start',
-					CASE WHEN COALESCE((extra->>'quota_weekly_start')::timestamptz, '1970-01-01'::timestamptz)
-						+ '168 hours'::interval <= NOW()
+					CASE WHEN `+weeklyExpiredExpr+`
 					THEN `+nowUTC+`
 					ELSE COALESCE(extra->>'quota_weekly_start', `+nowUTC+`) END
 				)
+				-- 固定模式重置时更新下次重置时间
+				|| CASE WHEN `+weeklyExpiredExpr+` AND `+nextWeeklyResetAtExpr+` IS NOT NULL
+				   THEN jsonb_build_object('quota_weekly_reset_at', `+nextWeeklyResetAtExpr+`)
+				   ELSE '{}'::jsonb END
 			ELSE '{}'::jsonb END
 		), updated_at = NOW()
 		WHERE id = $2 AND deleted_at IS NULL
@@ -1747,12 +1891,13 @@ func (r *accountRepository) IncrementQuotaUsed(ctx context.Context, id int64, am
 }
 
 // ResetQuotaUsed 重置账号所有维度的配额用量为 0
+// 保留固定重置模式的配置字段（quota_daily_reset_mode 等），仅清零用量和窗口起始时间
 func (r *accountRepository) ResetQuotaUsed(ctx context.Context, id int64) error {
 	_, err := r.sql.ExecContext(ctx,
 		`UPDATE accounts SET extra = (
 			COALESCE(extra, '{}'::jsonb)
 			|| '{"quota_used": 0, "quota_daily_used": 0, "quota_weekly_used": 0}'::jsonb
-		) - 'quota_daily_start' - 'quota_weekly_start', updated_at = NOW()
+		) - 'quota_daily_start' - 'quota_weekly_start' - 'quota_daily_reset_at' - 'quota_weekly_reset_at', updated_at = NOW()
 		WHERE id = $1 AND deleted_at IS NULL`,
 		id)
 	if err != nil {

backend/internal/repository/account_repo_integration_test.go

@@ -23,6 +23,7 @@ type AccountRepoSuite struct {
 
 type schedulerCacheRecorder struct {
 	setAccounts []*service.Account
+	accounts    map[int64]*service.Account
 }
 
 func (s *schedulerCacheRecorder) GetSnapshot(ctx context.Context, bucket service.SchedulerBucket) ([]*service.Account, bool, error) {
@@ -34,11 +35,20 @@ func (s *schedulerCacheRecorder) SetSnapshot(ctx context.Context, bucket service
 }
 
 func (s *schedulerCacheRecorder) GetAccount(ctx context.Context, accountID int64) (*service.Account, error) {
-	return nil, nil
+	if s.accounts == nil {
+		return nil, nil
+	}
+	return s.accounts[accountID], nil
 }
 
 func (s *schedulerCacheRecorder) SetAccount(ctx context.Context, account *service.Account) error {
 	s.setAccounts = append(s.setAccounts, account)
+	if s.accounts == nil {
+		s.accounts = make(map[int64]*service.Account)
+	}
+	if account != nil {
+		s.accounts[account.ID] = account
+	}
 	return nil
 }
 
@@ -132,6 +142,35 @@ func (s *AccountRepoSuite) TestUpdate_SyncSchedulerSnapshotOnDisabled() {
 	s.Require().Equal(service.StatusDisabled, cacheRecorder.setAccounts[0].Status)
 }
 
+func (s *AccountRepoSuite) TestUpdate_SyncSchedulerSnapshotOnCredentialsChange() {
+	account := mustCreateAccount(s.T(), s.client, &service.Account{
+		Name:        "sync-credentials-update",
+		Status:      service.StatusActive,
+		Schedulable: true,
+		Credentials: map[string]any{
+			"model_mapping": map[string]any{
+				"gpt-5": "gpt-5.1",
+			},
+		},
+	})
+	cacheRecorder := &schedulerCacheRecorder{}
+	s.repo.schedulerCache = cacheRecorder
+
+	account.Credentials = map[string]any{
+		"model_mapping": map[string]any{
+			"gpt-5": "gpt-5.2",
+		},
+	}
+	err := s.repo.Update(s.ctx, account)
+	s.Require().NoError(err, "Update")
+
+	s.Require().Len(cacheRecorder.setAccounts, 1)
+	s.Require().Equal(account.ID, cacheRecorder.setAccounts[0].ID)
+	mapping, ok := cacheRecorder.setAccounts[0].Credentials["model_mapping"].(map[string]any)
+	s.Require().True(ok)
+	s.Require().Equal("gpt-5.2", mapping["gpt-5"])
+}
+
 func (s *AccountRepoSuite) TestDelete() {
 	account := mustCreateAccount(s.T(), s.client, &service.Account{Name: "to-delete"})
 
@@ -175,6 +214,7 @@ func (s *AccountRepoSuite) TestListWithFilters() {
 		accType   string
 		status    string
 		search    string
+		groupID   int64
 		wantCount int
 		validate  func(accounts []service.Account)
 	}{
@@ -226,6 +266,21 @@ func (s *AccountRepoSuite) TestListWithFilters() {
 				s.Require().Contains(accounts[0].Name, "alpha")
 			},
 		},
+		{
+			name: "filter_by_ungrouped",
+			setup: func(client *dbent.Client) {
+				group := mustCreateGroup(s.T(), client, &service.Group{Name: "g-ungrouped"})
+				grouped := mustCreateAccount(s.T(), client, &service.Account{Name: "grouped-account"})
+				mustCreateAccount(s.T(), client, &service.Account{Name: "ungrouped-account"})
+				mustBindAccountToGroup(s.T(), client, grouped.ID, group.ID, 1)
+			},
+			groupID:   service.AccountListGroupUngrouped,
+			wantCount: 1,
+			validate: func(accounts []service.Account) {
+				s.Require().Equal("ungrouped-account", accounts[0].Name)
+				s.Require().Empty(accounts[0].GroupIDs)
+			},
+		},
 	}
 
 	for _, tt := range tests {
@@ -238,7 +293,7 @@ func (s *AccountRepoSuite) TestListWithFilters() {
 
 			tt.setup(client)
 
-			accounts, _, err := repo.ListWithFilters(ctx, pagination.PaginationParams{Page: 1, PageSize: 10}, tt.platform, tt.accType, tt.status, tt.search, 0)
+			accounts, _, err := repo.ListWithFilters(ctx, pagination.PaginationParams{Page: 1, PageSize: 10}, tt.platform, tt.accType, tt.status, tt.search, tt.groupID)
 			s.Require().NoError(err)
 			s.Require().Len(accounts, tt.wantCount)
 			if tt.validate != nil {
@@ -623,6 +678,96 @@ func (s *AccountRepoSuite) TestUpdateExtra_NilExtra() {
 	s.Require().Equal("val", got.Extra["key"])
 }
 
+func (s *AccountRepoSuite) TestUpdateExtra_SchedulerNeutralSkipsOutboxAndSyncsFreshSnapshot() {
+	account := mustCreateAccount(s.T(), s.client, &service.Account{
+		Name:     "acc-extra-neutral",
+		Platform: service.PlatformOpenAI,
+		Extra:    map[string]any{"codex_usage_updated_at": "old"},
+	})
+	cacheRecorder := &schedulerCacheRecorder{
+		accounts: map[int64]*service.Account{
+			account.ID: {
+				ID:       account.ID,
+				Platform: account.Platform,
+				Status:   service.StatusDisabled,
+				Extra: map[string]any{
+					"codex_usage_updated_at": "old",
+				},
+			},
+		},
+	}
+	s.repo.schedulerCache = cacheRecorder
+
+	updates := map[string]any{
+		"codex_usage_updated_at":     "2026-03-11T10:00:00Z",
+		"codex_5h_used_percent":      88.5,
+		"session_window_utilization": 0.42,
+	}
+	s.Require().NoError(s.repo.UpdateExtra(s.ctx, account.ID, updates))
+
+	got, err := s.repo.GetByID(s.ctx, account.ID)
+	s.Require().NoError(err)
+	s.Require().Equal("2026-03-11T10:00:00Z", got.Extra["codex_usage_updated_at"])
+	s.Require().Equal(88.5, got.Extra["codex_5h_used_percent"])
+	s.Require().Equal(0.42, got.Extra["session_window_utilization"])
+
+	var outboxCount int
+	s.Require().NoError(scanSingleRow(s.ctx, s.repo.sql, "SELECT COUNT(*) FROM scheduler_outbox", nil, &outboxCount))
+	s.Require().Zero(outboxCount)
+	s.Require().Len(cacheRecorder.setAccounts, 1)
+	s.Require().NotNil(cacheRecorder.accounts[account.ID])
+	s.Require().Equal(service.StatusActive, cacheRecorder.accounts[account.ID].Status)
+	s.Require().Equal("2026-03-11T10:00:00Z", cacheRecorder.accounts[account.ID].Extra["codex_usage_updated_at"])
+}
+
+func (s *AccountRepoSuite) TestUpdateExtra_ExhaustedCodexSnapshotSyncsSchedulerCache() {
+	account := mustCreateAccount(s.T(), s.client, &service.Account{
+		Name:     "acc-extra-codex-exhausted",
+		Platform: service.PlatformOpenAI,
+		Type:     service.AccountTypeOAuth,
+		Extra:    map[string]any{},
+	})
+	cacheRecorder := &schedulerCacheRecorder{}
+	s.repo.schedulerCache = cacheRecorder
+	_, err := s.repo.sql.ExecContext(s.ctx, "TRUNCATE scheduler_outbox")
+	s.Require().NoError(err)
+
+	s.Require().NoError(s.repo.UpdateExtra(s.ctx, account.ID, map[string]any{
+		"codex_7d_used_percent":        100.0,
+		"codex_7d_reset_at":            "2026-03-12T13:00:00Z",
+		"codex_7d_reset_after_seconds": 86400,
+	}))
+
+	var count int
+	err = scanSingleRow(s.ctx, s.repo.sql, "SELECT COUNT(*) FROM scheduler_outbox", nil, &count)
+	s.Require().NoError(err)
+	s.Require().Equal(0, count)
+	s.Require().Len(cacheRecorder.setAccounts, 1)
+	s.Require().Equal(account.ID, cacheRecorder.setAccounts[0].ID)
+	s.Require().Equal(service.StatusActive, cacheRecorder.setAccounts[0].Status)
+	s.Require().Equal(100.0, cacheRecorder.setAccounts[0].Extra["codex_7d_used_percent"])
+}
+
+func (s *AccountRepoSuite) TestUpdateExtra_SchedulerRelevantStillEnqueuesOutbox() {
+	account := mustCreateAccount(s.T(), s.client, &service.Account{
+		Name:     "acc-extra-mixed",
+		Platform: service.PlatformAntigravity,
+		Extra:    map[string]any{},
+	})
+	_, err := s.repo.sql.ExecContext(s.ctx, "TRUNCATE scheduler_outbox")
+	s.Require().NoError(err)
+
+	s.Require().NoError(s.repo.UpdateExtra(s.ctx, account.ID, map[string]any{
+		"mixed_scheduling":       true,
+		"codex_usage_updated_at": "2026-03-11T10:00:00Z",
+	}))
+
+	var count int
+	err = scanSingleRow(s.ctx, s.repo.sql, "SELECT COUNT(*) FROM scheduler_outbox", nil, &count)
+	s.Require().NoError(err)
+	s.Require().Equal(1, count)
+}
+
 // --- GetByCRSAccountID ---
 
 func (s *AccountRepoSuite) TestGetByCRSAccountID() {

backend/internal/repository/api_key_repo.go

@@ -452,6 +452,32 @@ func (r *apiKeyRepository) IncrementQuotaUsed(ctx context.Context, id int64, amo
 	return updated.QuotaUsed, nil
 }
 
+// IncrementQuotaUsedAndGetState atomically increments quota_used, conditionally marks the key
+// as quota_exhausted, and returns the latest quota state in one round trip.
+func (r *apiKeyRepository) IncrementQuotaUsedAndGetState(ctx context.Context, id int64, amount float64) (*service.APIKeyQuotaUsageState, error) {
+	query := `
+		UPDATE api_keys
+		SET
+			quota_used = quota_used + $1,
+			status = CASE
+				WHEN quota > 0 AND quota_used + $1 >= quota THEN $2
+				ELSE status
+			END,
+			updated_at = NOW()
+		WHERE id = $3 AND deleted_at IS NULL
+		RETURNING quota_used, quota, key, status
+	`
+
+	state := &service.APIKeyQuotaUsageState{}
+	if err := scanSingleRow(ctx, r.sql, query, []any{amount, service.StatusAPIKeyQuotaExhausted, id}, &state.QuotaUsed, &state.Quota, &state.Key, &state.Status); err != nil {
+		if err == sql.ErrNoRows {
+			return nil, service.ErrAPIKeyNotFound
+		}
+		return nil, err
+	}
+	return state, nil
+}
+
 func (r *apiKeyRepository) UpdateLastUsed(ctx context.Context, id int64, usedAt time.Time) error {
 	affected, err := r.client.APIKey.Update().
 		Where(apikey.IDEQ(id), apikey.DeletedAtIsNil()).

backend/internal/repository/api_key_repo_integration_test.go

@@ -417,6 +417,27 @@ func (s *APIKeyRepoSuite) TestIncrementQuotaUsed_DeletedKey() {
 	s.Require().ErrorIs(err, service.ErrAPIKeyNotFound, "已删除的 key 应返回 ErrAPIKeyNotFound")
 }
 
+func (s *APIKeyRepoSuite) TestIncrementQuotaUsedAndGetState() {
+	user := s.mustCreateUser("quota-state@test.com")
+	key := s.mustCreateApiKey(user.ID, "sk-quota-state", "QuotaState", nil)
+	key.Quota = 3
+	key.QuotaUsed = 1
+	s.Require().NoError(s.repo.Update(s.ctx, key), "Update quota")
+
+	state, err := s.repo.IncrementQuotaUsedAndGetState(s.ctx, key.ID, 2.5)
+	s.Require().NoError(err, "IncrementQuotaUsedAndGetState")
+	s.Require().NotNil(state)
+	s.Require().Equal(3.5, state.QuotaUsed)
+	s.Require().Equal(3.0, state.Quota)
+	s.Require().Equal(service.StatusAPIKeyQuotaExhausted, state.Status)
+	s.Require().Equal(key.Key, state.Key)
+
+	got, err := s.repo.GetByID(s.ctx, key.ID)
+	s.Require().NoError(err, "GetByID")
+	s.Require().Equal(3.5, got.QuotaUsed)
+	s.Require().Equal(service.StatusAPIKeyQuotaExhausted, got.Status)
+}
+
 // TestIncrementQuotaUsed_Concurrent 使用真实数据库验证并发原子性。
 // 注意：此测试使用 testEntClient（非事务隔离），数据会真正写入数据库。
 func TestIncrementQuotaUsed_Concurrent(t *testing.T) {

backend/internal/repository/backup_pg_dumper.go

@@ -0,0 +1,98 @@
+package repository
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"os/exec"
+
+	"github.com/Wei-Shaw/sub2api/internal/config"
+	"github.com/Wei-Shaw/sub2api/internal/service"
+)
+
+// PgDumper implements service.DBDumper using pg_dump/psql
+type PgDumper struct {
+	cfg *config.DatabaseConfig
+}
+
+// NewPgDumper creates a new PgDumper
+func NewPgDumper(cfg *config.Config) service.DBDumper {
+	return &PgDumper{cfg: &cfg.Database}
+}
+
+// Dump executes pg_dump and returns a streaming reader of the output
+func (d *PgDumper) Dump(ctx context.Context) (io.ReadCloser, error) {
+	args := []string{
+		"-h", d.cfg.Host,
+		"-p", fmt.Sprintf("%d", d.cfg.Port),
+		"-U", d.cfg.User,
+		"-d", d.cfg.DBName,
+		"--no-owner",
+		"--no-acl",
+		"--clean",
+		"--if-exists",
+	}
+
+	cmd := exec.CommandContext(ctx, "pg_dump", args...)
+	if d.cfg.Password != "" {
+		cmd.Env = append(cmd.Environ(), "PGPASSWORD="+d.cfg.Password)
+	}
+	if d.cfg.SSLMode != "" {
+		cmd.Env = append(cmd.Environ(), "PGSSLMODE="+d.cfg.SSLMode)
+	}
+
+	stdout, err := cmd.StdoutPipe()
+	if err != nil {
+		return nil, fmt.Errorf("create stdout pipe: %w", err)
+	}
+
+	if err := cmd.Start(); err != nil {
+		return nil, fmt.Errorf("start pg_dump: %w", err)
+	}
+
+	// 返回一个 ReadCloser：读 stdout，关闭时等待进程退出
+	return &cmdReadCloser{ReadCloser: stdout, cmd: cmd}, nil
+}
+
+// Restore executes psql to restore from a streaming reader
+func (d *PgDumper) Restore(ctx context.Context, data io.Reader) error {
+	args := []string{
+		"-h", d.cfg.Host,
+		"-p", fmt.Sprintf("%d", d.cfg.Port),
+		"-U", d.cfg.User,
+		"-d", d.cfg.DBName,
+		"--single-transaction",
+	}
+
+	cmd := exec.CommandContext(ctx, "psql", args...)
+	if d.cfg.Password != "" {
+		cmd.Env = append(cmd.Environ(), "PGPASSWORD="+d.cfg.Password)
+	}
+	if d.cfg.SSLMode != "" {
+		cmd.Env = append(cmd.Environ(), "PGSSLMODE="+d.cfg.SSLMode)
+	}
+
+	cmd.Stdin = data
+
+	output, err := cmd.CombinedOutput()
+	if err != nil {
+		return fmt.Errorf("%v: %s", err, string(output))
+	}
+	return nil
+}
+
+// cmdReadCloser wraps a command stdout pipe and waits for the process on Close
+type cmdReadCloser struct {
+	io.ReadCloser
+	cmd *exec.Cmd
+}
+
+func (c *cmdReadCloser) Close() error {
+	// Close the pipe first
+	_ = c.ReadCloser.Close()
+	// Wait for the process to exit
+	if err := c.cmd.Wait(); err != nil {
+		return fmt.Errorf("pg_dump exited with error: %w", err)
+	}
+	return nil
+}

backend/internal/repository/backup_s3_store.go

@@ -0,0 +1,117 @@
+package repository
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"io"
+	"time"
+
+	"github.com/aws/aws-sdk-go-v2/aws"
+	v4 "github.com/aws/aws-sdk-go-v2/aws/signer/v4"
+	awsconfig "github.com/aws/aws-sdk-go-v2/config"
+	"github.com/aws/aws-sdk-go-v2/credentials"
+	"github.com/aws/aws-sdk-go-v2/service/s3"
+
+	"github.com/Wei-Shaw/sub2api/internal/service"
+)
+
+// S3BackupStore implements service.BackupObjectStore using AWS S3 compatible storage
+type S3BackupStore struct {
+	client *s3.Client
+	bucket string
+}
+
+// NewS3BackupStoreFactory returns a BackupObjectStoreFactory that creates S3-backed stores
+func NewS3BackupStoreFactory() service.BackupObjectStoreFactory {
+	return func(ctx context.Context, cfg *service.BackupS3Config) (service.BackupObjectStore, error) {
+		region := cfg.Region
+		if region == "" {
+			region = "auto" // Cloudflare R2 默认 region
+		}
+
+		awsCfg, err := awsconfig.LoadDefaultConfig(ctx,
+			awsconfig.WithRegion(region),
+			awsconfig.WithCredentialsProvider(
+				credentials.NewStaticCredentialsProvider(cfg.AccessKeyID, cfg.SecretAccessKey, ""),
+			),
+		)
+		if err != nil {
+			return nil, fmt.Errorf("load aws config: %w", err)
+		}
+
+		client := s3.NewFromConfig(awsCfg, func(o *s3.Options) {
+			if cfg.Endpoint != "" {
+				o.BaseEndpoint = &cfg.Endpoint
+			}
+			if cfg.ForcePathStyle {
+				o.UsePathStyle = true
+			}
+			o.APIOptions = append(o.APIOptions, v4.SwapComputePayloadSHA256ForUnsignedPayloadMiddleware)
+			o.RequestChecksumCalculation = aws.RequestChecksumCalculationWhenRequired
+		})
+
+		return &S3BackupStore{client: client, bucket: cfg.Bucket}, nil
+	}
+}
+
+func (s *S3BackupStore) Upload(ctx context.Context, key string, body io.Reader, contentType string) (int64, error) {
+	// 读取全部内容以获取大小（S3 PutObject 需要知道内容长度）
+	// 注意：阿里云 OSS 不兼容 s3manager 分片上传的签名方式，因此使用 PutObject
+	data, err := io.ReadAll(body)
+	if err != nil {
+		return 0, fmt.Errorf("read body: %w", err)
+	}
+
+	_, err = s.client.PutObject(ctx, &s3.PutObjectInput{
+		Bucket:      &s.bucket,
+		Key:         &key,
+		Body:        bytes.NewReader(data),
+		ContentType: &contentType,
+	})
+	if err != nil {
+		return 0, fmt.Errorf("S3 PutObject: %w", err)
+	}
+	return int64(len(data)), nil
+}
+
+func (s *S3BackupStore) Download(ctx context.Context, key string) (io.ReadCloser, error) {
+	result, err := s.client.GetObject(ctx, &s3.GetObjectInput{
+		Bucket: &s.bucket,
+		Key:    &key,
+	})
+	if err != nil {
+		return nil, fmt.Errorf("S3 GetObject: %w", err)
+	}
+	return result.Body, nil
+}
+
+func (s *S3BackupStore) Delete(ctx context.Context, key string) error {
+	_, err := s.client.DeleteObject(ctx, &s3.DeleteObjectInput{
+		Bucket: &s.bucket,
+		Key:    &key,
+	})
+	return err
+}
+
+func (s *S3BackupStore) PresignURL(ctx context.Context, key string, expiry time.Duration) (string, error) {
+	presignClient := s3.NewPresignClient(s.client)
+	result, err := presignClient.PresignGetObject(ctx, &s3.GetObjectInput{
+		Bucket: &s.bucket,
+		Key:    &key,
+	}, s3.WithPresignExpires(expiry))
+	if err != nil {
+		return "", fmt.Errorf("presign url: %w", err)
+	}
+	return result.URL, nil
+}
+
+func (s *S3BackupStore) HeadBucket(ctx context.Context) error {
+	_, err := s.client.HeadBucket(ctx, &s3.HeadBucketInput{
+		Bucket: &s.bucket,
+	})
+	if err != nil {
+		return fmt.Errorf("S3 HeadBucket failed: %w", err)
+	}
+	return nil
+}

backend/internal/repository/billing_cache.go

@@ -20,6 +20,11 @@ const (
 	billingCacheTTL           = 5 * time.Minute
 	billingCacheJitter        = 30 * time.Second
 	rateLimitCacheTTL         = 7 * 24 * time.Hour // 7 days matches the longest window
+
+	// Rate limit window durations — must match service.RateLimitWindow* constants.
+	rateLimitWindow5h = 5 * time.Hour
+	rateLimitWindow1d = 24 * time.Hour
+	rateLimitWindow7d = 7 * 24 * time.Hour
 )
 
 // jitteredTTL 返回带随机抖动的 TTL，防止缓存雪崩
@@ -90,17 +95,40 @@ var (
 		return 1
 	`)
 
-	// updateRateLimitUsageScript atomically increments all three rate limit usage counters.
-	// Returns 0 if the key doesn't exist (cache miss), 1 on success.
+	// updateRateLimitUsageScript atomically increments all three rate limit usage counters
+	// with window expiration checking. If a window has expired, its usage is reset to cost
+	// (instead of accumulated) and the window timestamp is updated, matching the DB-side
+	// IncrementRateLimitUsage semantics.
+	//
+	// ARGV: [1]=cost, [2]=ttl_seconds, [3]=now_unix, [4]=window_5h_seconds, [5]=window_1d_seconds, [6]=window_7d_seconds
 	updateRateLimitUsageScript = redis.NewScript(`
 		local exists = redis.call('EXISTS', KEYS[1])
 		if exists == 0 then
 			return 0
 		end
 		local cost = tonumber(ARGV[1])
-		redis.call('HINCRBYFLOAT', KEYS[1], 'usage_5h', cost)
-		redis.call('HINCRBYFLOAT', KEYS[1], 'usage_1d', cost)
-		redis.call('HINCRBYFLOAT', KEYS[1], 'usage_7d', cost)
+		local now = tonumber(ARGV[3])
+		local win5h = tonumber(ARGV[4])
+		local win1d = tonumber(ARGV[5])
+		local win7d = tonumber(ARGV[6])
+
+		-- Helper: check if window is expired and update usage + window accordingly
+		-- Returns nothing, modifies the hash in-place.
+		local function update_window(usage_field, window_field, window_duration)
+			local w = tonumber(redis.call('HGET', KEYS[1], window_field) or 0)
+			if w == 0 or (now - w) >= window_duration then
+				-- Window expired or never started: reset usage to cost, start new window
+				redis.call('HSET', KEYS[1], usage_field, tostring(cost))
+				redis.call('HSET', KEYS[1], window_field, tostring(now))
+			else
+				-- Window still valid: accumulate
+				redis.call('HINCRBYFLOAT', KEYS[1], usage_field, cost)
+			end
+		end
+
+		update_window('usage_5h', 'window_5h', win5h)
+		update_window('usage_1d', 'window_1d', win1d)
+		update_window('usage_7d', 'window_7d', win7d)
 		redis.call('EXPIRE', KEYS[1], ARGV[2])
 		return 1
 	`)
@@ -280,7 +308,15 @@ func (c *billingCache) SetAPIKeyRateLimit(ctx context.Context, keyID int64, data
 
 func (c *billingCache) UpdateAPIKeyRateLimitUsage(ctx context.Context, keyID int64, cost float64) error {
 	key := billingRateLimitKey(keyID)
-	_, err := updateRateLimitUsageScript.Run(ctx, c.rdb, []string{key}, cost, int(rateLimitCacheTTL.Seconds())).Result()
+	now := time.Now().Unix()
+	_, err := updateRateLimitUsageScript.Run(ctx, c.rdb, []string{key},
+		cost,
+		int(rateLimitCacheTTL.Seconds()),
+		now,
+		int(rateLimitWindow5h.Seconds()),
+		int(rateLimitWindow1d.Seconds()),
+		int(rateLimitWindow7d.Seconds()),
+	).Result()
 	if err != nil && !errors.Is(err, redis.Nil) {
 		log.Printf("Warning: update rate limit usage cache failed for api key %d: %v", keyID, err)
 		return err