feat: implement resolveCreditsOveragesModelKey function to stabilize model key resolution for credit overages

frontend/src/components/account/CreateAccountModal.vue

@@ -2449,6 +2449,33 @@
             </div>
           </div>
         </div>
+        <div v-if="form.platform === 'antigravity'" class="mt-3 flex items-center gap-2">
+          <label class="flex cursor-pointer items-center gap-2">
+            <input
+              type="checkbox"
+              v-model="allowOverages"
+              class="h-4 w-4 rounded border-gray-300 text-primary-500 focus:ring-primary-500 dark:border-dark-500"
+            />
+            <span class="text-sm font-medium text-gray-700 dark:text-gray-300">
+              {{ t('admin.accounts.allowOverages') }}
+            </span>
+          </label>
+          <div class="group relative">
+            <span
+              class="inline-flex h-4 w-4 cursor-help items-center justify-center rounded-full bg-gray-200 text-xs text-gray-500 hover:bg-gray-300 dark:bg-dark-600 dark:text-gray-400 dark:hover:bg-dark-500"
+            >
+              ?
+            </span>
+            <div
+              class="pointer-events-none absolute left-0 top-full z-[100] mt-1.5 w-72 rounded bg-gray-900 px-3 py-2 text-xs text-white opacity-0 transition-opacity group-hover:opacity-100 dark:bg-gray-700"
+            >
+              {{ t('admin.accounts.allowOveragesTooltip') }}
+              <div
+                class="absolute bottom-full left-3 border-4 border-transparent border-b-gray-900 dark:border-b-gray-700"
+              ></div>
+            </div>
+          </div>
+        </div>
 
         <!-- Group Selection - 仅标准模式显示 -->
         <GroupSelector
@@ -2991,6 +3018,7 @@ const openaiAPIKeyResponsesWebSocketV2Mode = ref<OpenAIWSMode>(OPENAI_WS_MODE_OF
 const codexCLIOnlyEnabled = ref(false)
 const anthropicPassthroughEnabled = ref(false)
 const mixedScheduling = ref(false) // For antigravity accounts: enable mixed scheduling
+const allowOverages = ref(false) // For antigravity accounts: enable AI Credits overages
 const antigravityAccountType = ref<'oauth' | 'upstream'>('oauth') // For antigravity: oauth or upstream
 const soraAccountType = ref<'oauth' | 'apikey'>('oauth') // For sora: oauth or apikey (upstream)
 const upstreamBaseUrl = ref('') // For upstream type: base URL
@@ -3017,6 +3045,13 @@ const getTempUnschedRuleKey = createStableObjectKeyResolver<TempUnschedRuleForm>
 const geminiOAuthType = ref<'code_assist' | 'google_one' | 'ai_studio'>('google_one')
 const geminiAIStudioOAuthEnabled = ref(false)
 
+function buildAntigravityExtra(): Record<string, unknown> | undefined {
+  const extra: Record<string, unknown> = {}
+  if (mixedScheduling.value) extra.mixed_scheduling = true
+  if (allowOverages.value) extra.allow_overages = true
+  return Object.keys(extra).length > 0 ? extra : undefined
+}
+
 const showMixedChannelWarning = ref(false)
 const mixedChannelWarningDetails = ref<{ groupName: string; currentPlatform: string; otherPlatform: string } | null>(
   null
@@ -3282,6 +3317,7 @@ watch(
       accountCategory.value = 'oauth-based'
       antigravityAccountType.value = 'oauth'
     } else {
+      allowOverages.value = false
       antigravityWhitelistModels.value = []
       antigravityModelMappings.value = []
       antigravityModelRestrictionMode.value = 'mapping'
@@ -3712,6 +3748,7 @@ const resetForm = () => {
   sessionIdMaskingEnabled.value = false
   cacheTTLOverrideEnabled.value = false
   cacheTTLOverrideTarget.value = '5m'
+  allowOverages.value = false
   antigravityAccountType.value = 'oauth'
   upstreamBaseUrl.value = ''
   upstreamApiKey.value = ''
@@ -3960,7 +3997,7 @@ const handleSubmit = async () => {
 
     applyInterceptWarmup(credentials, interceptWarmupRequests.value, 'create')
 
-    const extra = mixedScheduling.value ? { mixed_scheduling: true } : undefined
+    const extra = buildAntigravityExtra()
     await createAccountAndFinish(form.platform, 'apikey', credentials, extra)
     return
   }
@@ -4706,7 +4743,7 @@ const handleAntigravityExchange = async (authCode: string) => {
 		if (antigravityModelMapping) {
 			credentials.model_mapping = antigravityModelMapping
 		}
-		const extra = mixedScheduling.value ? { mixed_scheduling: true } : undefined
+		const extra = buildAntigravityExtra()
 		await createAccountAndFinish('antigravity', 'oauth', credentials, extra)
   } catch (error: any) {
     antigravityOAuth.error.value = error.response?.data?.detail || t('admin.accounts.oauth.authFailed')

frontend/src/components/account/EditAccountModal.vue

@@ -1610,6 +1610,33 @@
             </div>
           </div>
         </div>
+        <div v-if="account?.platform === 'antigravity'" class="mt-3 flex items-center gap-2">
+          <label class="flex cursor-pointer items-center gap-2">
+            <input
+              type="checkbox"
+              v-model="allowOverages"
+              class="h-4 w-4 rounded border-gray-300 text-primary-500 focus:ring-primary-500 dark:border-dark-500"
+            />
+            <span class="text-sm font-medium text-gray-700 dark:text-gray-300">
+              {{ t('admin.accounts.allowOverages') }}
+            </span>
+          </label>
+          <div class="group relative">
+            <span
+              class="inline-flex h-4 w-4 cursor-help items-center justify-center rounded-full bg-gray-200 text-xs text-gray-500 hover:bg-gray-300 dark:bg-dark-600 dark:text-gray-400 dark:hover:bg-dark-500"
+            >
+              ?
+            </span>
+            <div
+              class="pointer-events-none absolute left-0 top-full z-[100] mt-1.5 w-72 rounded bg-gray-900 px-3 py-2 text-xs text-white opacity-0 transition-opacity group-hover:opacity-100 dark:bg-gray-700"
+            >
+              {{ t('admin.accounts.allowOveragesTooltip') }}
+              <div
+                class="absolute bottom-full left-3 border-4 border-transparent border-b-gray-900 dark:border-b-gray-700"
+              ></div>
+            </div>
+          </div>
+        </div>
       </div>
 
       <!-- Group Selection - 仅标准模式显示 -->
@@ -1778,6 +1805,7 @@ const customErrorCodeInput = ref<number | null>(null)
 const interceptWarmupRequests = ref(false)
 const autoPauseOnExpired = ref(false)
 const mixedScheduling = ref(false) // For antigravity accounts: enable mixed scheduling
+const allowOverages = ref(false) // For antigravity accounts: enable AI Credits overages
 const antigravityModelRestrictionMode = ref<'whitelist' | 'mapping'>('whitelist')
 const antigravityWhitelistModels = ref<string[]>([])
 const antigravityModelMappings = ref<ModelMapping[]>([])
@@ -1980,8 +2008,11 @@ watch(
       autoPauseOnExpired.value = newAccount.auto_pause_on_expired === true
 
       // Load mixed scheduling setting (only for antigravity accounts)
+      mixedScheduling.value = false
+      allowOverages.value = false
       const extra = newAccount.extra as Record<string, unknown> | undefined
       mixedScheduling.value = extra?.mixed_scheduling === true
+      allowOverages.value = extra?.allow_overages === true
 
       // Load OpenAI passthrough toggle (OpenAI OAuth/API Key)
       openaiPassthroughEnabled.value = false
@@ -2822,7 +2853,7 @@ const handleSubmit = async () => {
       updatePayload.credentials = newCredentials
     }
 
-    // For antigravity accounts, handle mixed_scheduling in extra
+    // For antigravity accounts, handle mixed_scheduling and allow_overages in extra
     if (props.account.platform === 'antigravity') {
       const currentExtra = (props.account.extra as Record<string, unknown>) || {}
       const newExtra: Record<string, unknown> = { ...currentExtra }
@@ -2831,6 +2862,11 @@ const handleSubmit = async () => {
       } else {
         delete newExtra.mixed_scheduling
       }
+      if (allowOverages.value) {
+        newExtra.allow_overages = true
+      } else {
+        delete newExtra.allow_overages
+      }
       updatePayload.extra = newExtra
     }
 

frontend/src/i18n/locales/en.ts

@@ -2239,6 +2239,9 @@ export default {
       mixedSchedulingHint: 'Enable to participate in Anthropic/Gemini group scheduling',
       mixedSchedulingTooltip:
         '!! WARNING !! Antigravity Claude and Anthropic Claude cannot be used in the same context. If you have both Anthropic and Antigravity accounts, enabling this option will cause frequent 400 errors. When enabled, please use the group feature to isolate Antigravity accounts from Anthropic accounts. Make sure you understand this before enabling!!',
+      allowOverages: 'Allow Overages (AI Credits)',
+      allowOveragesTooltip:
+        'Only use AI Credits after free quota is explicitly exhausted. Ordinary concurrent 429 rate limits will not switch to overages.',
       creating: 'Creating...',
       updating: 'Updating...',
       accountCreated: 'Account created successfully',

frontend/src/i18n/locales/zh.ts

@@ -2389,6 +2389,9 @@ export default {
       mixedSchedulingHint: '启用后可参与 Anthropic/Gemini 分组的调度',
       mixedSchedulingTooltip:
         '！！注意！！ Antigravity Claude 和 Anthropic Claude 无法在同个上下文中使用，如果你同时有 Anthropic 账号和 Antigravity 账号，开启此选项会导致经常 400 报错。开启后，请用分组功能做好 Antigravity 账号和 Anthropic 账号的隔离。一定要弄明白再开启！！',
+      allowOverages: '允许超量请求 (AI Credits)',
+      allowOveragesTooltip:
+        '仅在免费配额被明确判定为耗尽后才会使用 AI Credits。普通并发 429 限流不会切换到超量请求。',
       creating: '创建中...',
       updating: '更新中...',
       accountCreated: '账号创建成功',