feat(mcp): add OAuth support for HTTP/SSE MCP servers (#908)

add oauth schema to MCP server config (extensions_config.json) support client_credentials and refresh_token grants implement token manager with caching and pre-expiry refresh inject OAuth Authorization header for MCP tool discovery and tool calls extend MCP gateway config models to read/write OAuth settings update docs and examples for OAuth configuration add unit tests for token fetch/cache and header injection
2026-04-02 22:02:13 +08:00 · 2026-03-01 22:38:58 +08:00
parent 80316c131e
commit a2f91c7594
11 changed files with 497 additions and 20 deletions
--- a/README.md
+++ b/README.md
@@ -20,21 +20,31 @@ Learn more and see **real demos** on our official website.

 ## Table of Contents

- [Quick Start](#quick-start)
- [Sandbox Mode](#sandbox-mode)
- [From Deep Research to Super Agent Harness](#from-deep-research-to-super-agent-harness)
- [Core Features](#core-features)
-  - [Skills & Tools](#skills--tools)
-  - [Sub-Agents](#sub-agents)
-  - [Sandbox & File System](#sandbox--file-system)
-  - [Context Engineering](#context-engineering)
-  - [Long-Term Memory](#long-term-memory)
- [Recommended Models](#recommended-models)
- [Documentation](#documentation)
- [Contributing](#contributing)
- [License](#license)
- [Acknowledgments](#acknowledgments)
- [Star History](#star-history)
+- [🦌 DeerFlow - 2.0](#-deerflow---20)
+  - [Offiical Website](#offiical-website)
+  - [Table of Contents](#table-of-contents)
+  - [Quick Start](#quick-start)
+    - [Configuration](#configuration)
+    - [Running the Application](#running-the-application)
+      - [Option 1: Docker (Recommended)](#option-1-docker-recommended)
+      - [Option 2: Local Development](#option-2-local-development)
+    - [Advanced](#advanced)
+      - [Sandbox Mode](#sandbox-mode)
+      - [MCP Server](#mcp-server)
+  - [From Deep Research to Super Agent Harness](#from-deep-research-to-super-agent-harness)
+  - [Core Features](#core-features)
+    - [Skills \& Tools](#skills--tools)
+    - [Sub-Agents](#sub-agents)
+    - [Sandbox \& File System](#sandbox--file-system)
+    - [Context Engineering](#context-engineering)
+    - [Long-Term Memory](#long-term-memory)
+  - [Recommended Models](#recommended-models)
+  - [Documentation](#documentation)
+  - [Contributing](#contributing)
+  - [License](#license)
+  - [Acknowledgments](#acknowledgments)
+    - [Key Contributors](#key-contributors)
+  - [Star History](#star-history)

 ## Quick Start

@@ -155,6 +165,7 @@ See the [Sandbox Configuration Guide](backend/docs/CONFIGURATION.md#sandbox) to
 #### MCP Server

 DeerFlow supports configurable MCP servers and skills to extend its capabilities.
+For HTTP/SSE MCP servers, OAuth token flows are supported (`client_credentials`, `refresh_token`).
 See the [MCP Server Guide](backend/docs/MCP_SERVER.md) for detailed instructions.

 ## From Deep Research to Super Agent Harness
--- a/backend/CLAUDE.md
+++ b/backend/CLAUDE.md
@@ -224,6 +224,7 @@ Proxied through nginx: `/api/langgraph/*` → LangGraph, all other `/api/*` →
 - **Lazy initialization**: Tools loaded on first use via `get_cached_mcp_tools()`
 - **Cache invalidation**: Detects config file changes via mtime comparison
 - **Transports**: stdio (command-based), SSE, HTTP
+- **OAuth (HTTP/SSE)**: Supports token endpoint flows (`client_credentials`, `refresh_token`) with automatic token refresh + Authorization header injection
 - **Runtime updates**: Gateway API saves to extensions_config.json; LangGraph detects via mtime

 ### Skills System (`src/skills/`)
@@ -287,7 +288,7 @@ Proxied through nginx: `/api/langgraph/*` → LangGraph, all other `/api/*` →
 - `memory` - Memory system (enabled, storage_path, debounce_seconds, model_name, max_facts, fact_confidence_threshold, injection_enabled, max_injection_tokens)

 **`extensions_config.json`**:
- `mcpServers` - Map of server name → config (enabled, type, command, args, env, url, headers, description)
+- `mcpServers` - Map of server name → config (enabled, type, command, args, env, url, headers, oauth, description)
 - `skills` - Map of skill name → state (enabled)

 Both can be modified at runtime via Gateway API endpoints or `DeerFlowClient` methods.
--- a/backend/README.md
+++ b/backend/README.md
@@ -264,6 +264,18 @@ MCP servers and skill states in a single file:
      "command": "npx",
      "args": ["-y", "@modelcontextprotocol/server-github"],
      "env": {"GITHUB_TOKEN": "$GITHUB_TOKEN"}
+    },
+    "secure-http": {
+      "enabled": true,
+      "type": "http",
+      "url": "https://api.example.com/mcp",
+      "oauth": {
+        "enabled": true,
+        "token_url": "https://auth.example.com/oauth/token",
+        "grant_type": "client_credentials",
+        "client_id": "$MCP_OAUTH_CLIENT_ID",
+        "client_secret": "$MCP_OAUTH_CLIENT_SECRET"
+      }
    }
  },
  "skills": {
--- a/backend/docs/API.md
+++ b/backend/docs/API.md
@@ -503,6 +503,8 @@ All APIs return errors in a consistent format:

 Currently, DeerFlow does not implement authentication. All APIs are accessible without credentials.

+Note: This is about DeerFlow API authentication. MCP outbound connections can still use OAuth for configured HTTP/SSE MCP servers.
+
 For production deployments, it is recommended to:
 1. Use Nginx for basic auth or OAuth integration
 2. Deploy behind a VPN or private network
--- a/backend/docs/MCP_SERVER.md
+++ b/backend/docs/MCP_SERVER.md
@@ -14,6 +14,37 @@ DeerFlow supports configurable MCP servers and skills to extend its capabilities
 3. Configure each server’s command, arguments, and environment variables as needed.
 4. Restart the application to load and register MCP tools.

+## OAuth Support (HTTP/SSE MCP Servers)
+
+For `http` and `sse` MCP servers, DeerFlow supports OAuth token acquisition and automatic token refresh.
+
+- Supported grants: `client_credentials`, `refresh_token`
+- Configure per-server `oauth` block in `extensions_config.json`
+- Secrets should be provided via environment variables (for example: `$MCP_OAUTH_CLIENT_SECRET`)
+
+Example:
+
+```json
+{
+   "mcpServers": {
+      "secure-http-server": {
+         "enabled": true,
+         "type": "http",
+         "url": "https://api.example.com/mcp",
+         "oauth": {
+            "enabled": true,
+            "token_url": "https://auth.example.com/oauth/token",
+            "grant_type": "client_credentials",
+            "client_id": "$MCP_OAUTH_CLIENT_ID",
+            "client_secret": "$MCP_OAUTH_CLIENT_SECRET",
+            "scope": "mcp.read",
+            "refresh_skew_seconds": 60
+         }
+      }
+   }
+}
+```
+
 ## How It Works

 MCP servers expose tools that are automatically discovered and integrated into DeerFlow’s agent system at runtime. Once enabled, these tools become available to agents without additional code changes.
--- a/backend/src/config/extensions_config.py
+++ b/backend/src/config/extensions_config.py
@@ -3,11 +3,34 @@
 import json
 import os
 from pathlib import Path
-from typing import Any
+from typing import Any, Literal

 from pydantic import BaseModel, ConfigDict, Field


+class McpOAuthConfig(BaseModel):
+    """OAuth configuration for an MCP server (HTTP/SSE transports)."""
+
+    enabled: bool = Field(default=True, description="Whether OAuth token injection is enabled")
+    token_url: str = Field(description="OAuth token endpoint URL")
+    grant_type: Literal["client_credentials", "refresh_token"] = Field(
+        default="client_credentials",
+        description="OAuth grant type",
+    )
+    client_id: str | None = Field(default=None, description="OAuth client ID")
+    client_secret: str | None = Field(default=None, description="OAuth client secret")
+    refresh_token: str | None = Field(default=None, description="OAuth refresh token (for refresh_token grant)")
+    scope: str | None = Field(default=None, description="OAuth scope")
+    audience: str | None = Field(default=None, description="OAuth audience (provider-specific)")
+    token_field: str = Field(default="access_token", description="Field name containing access token in token response")
+    token_type_field: str = Field(default="token_type", description="Field name containing token type in token response")
+    expires_in_field: str = Field(default="expires_in", description="Field name containing expiry (seconds) in token response")
+    default_token_type: str = Field(default="Bearer", description="Default token type when missing in token response")
+    refresh_skew_seconds: int = Field(default=60, description="Refresh token this many seconds before expiry")
+    extra_token_params: dict[str, str] = Field(default_factory=dict, description="Additional form params sent to token endpoint")
+    model_config = ConfigDict(extra="allow")
+
+
 class McpServerConfig(BaseModel):
    """Configuration for a single MCP server."""

@@ -18,6 +41,7 @@ class McpServerConfig(BaseModel):
    env: dict[str, str] = Field(default_factory=dict, description="Environment variables for the MCP server")
    url: str | None = Field(default=None, description="URL of the MCP server (for sse or http type)")
    headers: dict[str, str] = Field(default_factory=dict, description="HTTP headers to send (for sse or http type)")
+    oauth: McpOAuthConfig | None = Field(default=None, description="OAuth configuration (for sse or http type)")
    description: str = Field(default="", description="Human-readable description of what this MCP server provides")
    model_config = ConfigDict(extra="allow")

--- a/backend/src/gateway/routers/mcp.py
+++ b/backend/src/gateway/routers/mcp.py
@@ -1,6 +1,7 @@
 import json
 import logging
 from pathlib import Path
+from typing import Literal

 from fastapi import APIRouter, HTTPException
 from pydantic import BaseModel, Field
@@ -11,6 +12,25 @@ logger = logging.getLogger(__name__)
 router = APIRouter(prefix="/api", tags=["mcp"])


+class McpOAuthConfigResponse(BaseModel):
+    """OAuth configuration for an MCP server."""
+
+    enabled: bool = Field(default=True, description="Whether OAuth token injection is enabled")
+    token_url: str = Field(default="", description="OAuth token endpoint URL")
+    grant_type: Literal["client_credentials", "refresh_token"] = Field(default="client_credentials", description="OAuth grant type")
+    client_id: str | None = Field(default=None, description="OAuth client ID")
+    client_secret: str | None = Field(default=None, description="OAuth client secret")
+    refresh_token: str | None = Field(default=None, description="OAuth refresh token")
+    scope: str | None = Field(default=None, description="OAuth scope")
+    audience: str | None = Field(default=None, description="OAuth audience")
+    token_field: str = Field(default="access_token", description="Token response field containing access token")
+    token_type_field: str = Field(default="token_type", description="Token response field containing token type")
+    expires_in_field: str = Field(default="expires_in", description="Token response field containing expires-in seconds")
+    default_token_type: str = Field(default="Bearer", description="Default token type when response omits token_type")
+    refresh_skew_seconds: int = Field(default=60, description="Refresh this many seconds before expiry")
+    extra_token_params: dict[str, str] = Field(default_factory=dict, description="Additional form params sent to token endpoint")
+
+
 class McpServerConfigResponse(BaseModel):
    """Response model for MCP server configuration."""

@@ -21,6 +41,7 @@ class McpServerConfigResponse(BaseModel):
    env: dict[str, str] = Field(default_factory=dict, description="Environment variables for the MCP server")
    url: str | None = Field(default=None, description="URL of the MCP server (for sse or http type)")
    headers: dict[str, str] = Field(default_factory=dict, description="HTTP headers to send (for sse or http type)")
+    oauth: McpOAuthConfigResponse | None = Field(default=None, description="OAuth configuration for MCP HTTP/SSE servers")
    description: str = Field(default="", description="Human-readable description of what this MCP server provides")


--- a/backend/src/mcp/oauth.py
+++ b/backend/src/mcp/oauth.py
@@ -0,0 +1,150 @@
+"""OAuth token support for MCP HTTP/SSE servers."""
+
+from __future__ import annotations
+
+import asyncio
+import logging
+from dataclasses import dataclass
+from datetime import UTC, datetime, timedelta
+from typing import Any
+
+from src.config.extensions_config import ExtensionsConfig, McpOAuthConfig
+
+logger = logging.getLogger(__name__)
+
+
+@dataclass
+class _OAuthToken:
+    """Cached OAuth token."""
+
+    access_token: str
+    token_type: str
+    expires_at: datetime
+
+
+class OAuthTokenManager:
+    """Acquire/cache/refresh OAuth tokens for MCP servers."""
+
+    def __init__(self, oauth_by_server: dict[str, McpOAuthConfig]):
+        self._oauth_by_server = oauth_by_server
+        self._tokens: dict[str, _OAuthToken] = {}
+        self._locks: dict[str, asyncio.Lock] = {name: asyncio.Lock() for name in oauth_by_server}
+
+    @classmethod
+    def from_extensions_config(cls, extensions_config: ExtensionsConfig) -> OAuthTokenManager:
+        oauth_by_server: dict[str, McpOAuthConfig] = {}
+        for server_name, server_config in extensions_config.get_enabled_mcp_servers().items():
+            if server_config.oauth and server_config.oauth.enabled:
+                oauth_by_server[server_name] = server_config.oauth
+        return cls(oauth_by_server)
+
+    def has_oauth_servers(self) -> bool:
+        return bool(self._oauth_by_server)
+
+    def oauth_server_names(self) -> list[str]:
+        return list(self._oauth_by_server.keys())
+
+    async def get_authorization_header(self, server_name: str) -> str | None:
+        oauth = self._oauth_by_server.get(server_name)
+        if not oauth:
+            return None
+
+        token = self._tokens.get(server_name)
+        if token and not self._is_expiring(token, oauth):
+            return f"{token.token_type} {token.access_token}"
+
+        lock = self._locks[server_name]
+        async with lock:
+            token = self._tokens.get(server_name)
+            if token and not self._is_expiring(token, oauth):
+                return f"{token.token_type} {token.access_token}"
+
+            fresh = await self._fetch_token(oauth)
+            self._tokens[server_name] = fresh
+            logger.info(f"Refreshed OAuth access token for MCP server: {server_name}")
+            return f"{fresh.token_type} {fresh.access_token}"
+
+    @staticmethod
+    def _is_expiring(token: _OAuthToken, oauth: McpOAuthConfig) -> bool:
+        now = datetime.now(UTC)
+        return token.expires_at <= now + timedelta(seconds=max(oauth.refresh_skew_seconds, 0))
+
+    async def _fetch_token(self, oauth: McpOAuthConfig) -> _OAuthToken:
+        import httpx  # pyright: ignore[reportMissingImports]
+
+        data: dict[str, str] = {
+            "grant_type": oauth.grant_type,
+            **oauth.extra_token_params,
+        }
+
+        if oauth.scope:
+            data["scope"] = oauth.scope
+        if oauth.audience:
+            data["audience"] = oauth.audience
+
+        if oauth.grant_type == "client_credentials":
+            if not oauth.client_id or not oauth.client_secret:
+                raise ValueError("OAuth client_credentials requires client_id and client_secret")
+            data["client_id"] = oauth.client_id
+            data["client_secret"] = oauth.client_secret
+        elif oauth.grant_type == "refresh_token":
+            if not oauth.refresh_token:
+                raise ValueError("OAuth refresh_token grant requires refresh_token")
+            data["refresh_token"] = oauth.refresh_token
+            if oauth.client_id:
+                data["client_id"] = oauth.client_id
+            if oauth.client_secret:
+                data["client_secret"] = oauth.client_secret
+        else:
+            raise ValueError(f"Unsupported OAuth grant type: {oauth.grant_type}")
+
+        async with httpx.AsyncClient(timeout=15.0) as client:
+            response = await client.post(oauth.token_url, data=data)
+            response.raise_for_status()
+            payload = response.json()
+
+        access_token = payload.get(oauth.token_field)
+        if not access_token:
+            raise ValueError(f"OAuth token response missing '{oauth.token_field}'")
+
+        token_type = str(payload.get(oauth.token_type_field, oauth.default_token_type) or oauth.default_token_type)
+
+        expires_in_raw = payload.get(oauth.expires_in_field, 3600)
+        try:
+            expires_in = int(expires_in_raw)
+        except (TypeError, ValueError):
+            expires_in = 3600
+
+        expires_at = datetime.now(UTC) + timedelta(seconds=max(expires_in, 1))
+        return _OAuthToken(access_token=access_token, token_type=token_type, expires_at=expires_at)
+
+
+def build_oauth_tool_interceptor(extensions_config: ExtensionsConfig) -> Any | None:
+    """Build a tool interceptor that injects OAuth Authorization headers."""
+    token_manager = OAuthTokenManager.from_extensions_config(extensions_config)
+    if not token_manager.has_oauth_servers():
+        return None
+
+    async def oauth_interceptor(request: Any, handler: Any) -> Any:
+        header = await token_manager.get_authorization_header(request.server_name)
+        if not header:
+            return await handler(request)
+
+        updated_headers = dict(request.headers or {})
+        updated_headers["Authorization"] = header
+        return await handler(request.override(headers=updated_headers))
+
+    return oauth_interceptor
+
+
+async def get_initial_oauth_headers(extensions_config: ExtensionsConfig) -> dict[str, str]:
+    """Get initial OAuth Authorization headers for MCP server connections."""
+    token_manager = OAuthTokenManager.from_extensions_config(extensions_config)
+    if not token_manager.has_oauth_servers():
+        return {}
+
+    headers: dict[str, str] = {}
+    for server_name in token_manager.oauth_server_names():
+        headers[server_name] = await token_manager.get_authorization_header(server_name) or ""
+
+    return {name: value for name, value in headers.items() if value}
--- a/backend/src/mcp/tools.py
+++ b/backend/src/mcp/tools.py
@@ -6,6 +6,7 @@ from langchain_core.tools import BaseTool

 from src.config.extensions_config import ExtensionsConfig
 from src.mcp.client import build_servers_config
+from src.mcp.oauth import build_oauth_tool_interceptor, get_initial_oauth_headers

 logger = logging.getLogger(__name__)

@@ -36,7 +37,23 @@ async def get_mcp_tools() -> list[BaseTool]:
    try:
        # Create the multi-server MCP client
        logger.info(f"Initializing MCP client with {len(servers_config)} server(s)")
-        client = MultiServerMCPClient(servers_config)
+
+        # Inject initial OAuth headers for server connections (tool discovery/session init)
+        initial_oauth_headers = await get_initial_oauth_headers(extensions_config)
+        for server_name, auth_header in initial_oauth_headers.items():
+            if server_name not in servers_config:
+                continue
+            if servers_config[server_name].get("transport") in ("sse", "http"):
+                existing_headers = dict(servers_config[server_name].get("headers", {}))
+                existing_headers["Authorization"] = auth_header
+                servers_config[server_name]["headers"] = existing_headers
+
+        tool_interceptors = []
+        oauth_interceptor = build_oauth_tool_interceptor(extensions_config)
+        if oauth_interceptor is not None:
+            tool_interceptors.append(oauth_interceptor)
+
+        client = MultiServerMCPClient(servers_config, tool_interceptors=tool_interceptors)

        # Get all tools from all servers
        tools = await client.get_tools()
--- a/backend/tests/test_mcp_oauth.py
+++ b/backend/tests/test_mcp_oauth.py
@@ -0,0 +1,191 @@
+"""Tests for MCP OAuth support."""
+
+from __future__ import annotations
+
+import asyncio
+from typing import Any
+
+from src.config.extensions_config import ExtensionsConfig
+from src.mcp.oauth import OAuthTokenManager, build_oauth_tool_interceptor, get_initial_oauth_headers
+
+
+class _MockResponse:
+    def __init__(self, payload: dict[str, Any]):
+        self._payload = payload
+
+    def raise_for_status(self) -> None:
+        return None
+
+    def json(self) -> dict[str, Any]:
+        return self._payload
+
+
+class _MockAsyncClient:
+    def __init__(self, payload: dict[str, Any], post_calls: list[dict[str, Any]], **kwargs):
+        self._payload = payload
+        self._post_calls = post_calls
+
+    async def __aenter__(self):
+        return self
+
+    async def __aexit__(self, exc_type, exc, tb):
+        return False
+
+    async def post(self, url: str, data: dict[str, Any]):
+        self._post_calls.append({"url": url, "data": data})
+        return _MockResponse(self._payload)
+
+
+def test_oauth_token_manager_fetches_and_caches_token(monkeypatch):
+    post_calls: list[dict[str, Any]] = []
+
+    def _client_factory(*args, **kwargs):
+        return _MockAsyncClient(
+            payload={
+                "access_token": "token-123",
+                "token_type": "Bearer",
+                "expires_in": 3600,
+            },
+            post_calls=post_calls,
+            **kwargs,
+        )
+
+    monkeypatch.setattr("httpx.AsyncClient", _client_factory)
+
+    config = ExtensionsConfig.model_validate(
+        {
+            "mcpServers": {
+                "secure-http": {
+                    "enabled": True,
+                    "type": "http",
+                    "url": "https://api.example.com/mcp",
+                    "oauth": {
+                        "enabled": True,
+                        "token_url": "https://auth.example.com/oauth/token",
+                        "grant_type": "client_credentials",
+                        "client_id": "client-id",
+                        "client_secret": "client-secret",
+                    },
+                }
+            }
+        }
+    )
+
+    manager = OAuthTokenManager.from_extensions_config(config)
+
+    first = asyncio.run(manager.get_authorization_header("secure-http"))
+    second = asyncio.run(manager.get_authorization_header("secure-http"))
+
+    assert first == "Bearer token-123"
+    assert second == "Bearer token-123"
+    assert len(post_calls) == 1
+    assert post_calls[0]["url"] == "https://auth.example.com/oauth/token"
+    assert post_calls[0]["data"]["grant_type"] == "client_credentials"
+
+
+def test_build_oauth_interceptor_injects_authorization_header(monkeypatch):
+    post_calls: list[dict[str, Any]] = []
+
+    def _client_factory(*args, **kwargs):
+        return _MockAsyncClient(
+            payload={
+                "access_token": "token-abc",
+                "token_type": "Bearer",
+                "expires_in": 3600,
+            },
+            post_calls=post_calls,
+            **kwargs,
+        )
+
+    monkeypatch.setattr("httpx.AsyncClient", _client_factory)
+
+    config = ExtensionsConfig.model_validate(
+        {
+            "mcpServers": {
+                "secure-sse": {
+                    "enabled": True,
+                    "type": "sse",
+                    "url": "https://api.example.com/mcp",
+                    "oauth": {
+                        "enabled": True,
+                        "token_url": "https://auth.example.com/oauth/token",
+                        "grant_type": "client_credentials",
+                        "client_id": "client-id",
+                        "client_secret": "client-secret",
+                    },
+                }
+            }
+        }
+    )
+
+    interceptor = build_oauth_tool_interceptor(config)
+    assert interceptor is not None
+
+    class _Request:
+        def __init__(self):
+            self.server_name = "secure-sse"
+            self.headers = {"X-Test": "1"}
+
+        def override(self, **kwargs):
+            updated = _Request()
+            updated.server_name = self.server_name
+            updated.headers = kwargs.get("headers")
+            return updated
+
+    captured: dict[str, Any] = {}
+
+    async def _handler(request):
+        captured["headers"] = request.headers
+        return "ok"
+
+    result = asyncio.run(interceptor(_Request(), _handler))
+
+    assert result == "ok"
+    assert captured["headers"]["Authorization"] == "Bearer token-abc"
+    assert captured["headers"]["X-Test"] == "1"
+
+
+def test_get_initial_oauth_headers(monkeypatch):
+    post_calls: list[dict[str, Any]] = []
+
+    def _client_factory(*args, **kwargs):
+        return _MockAsyncClient(
+            payload={
+                "access_token": "token-initial",
+                "token_type": "Bearer",
+                "expires_in": 3600,
+            },
+            post_calls=post_calls,
+            **kwargs,
+        )
+
+    monkeypatch.setattr("httpx.AsyncClient", _client_factory)
+
+    config = ExtensionsConfig.model_validate(
+        {
+            "mcpServers": {
+                "secure-http": {
+                    "enabled": True,
+                    "type": "http",
+                    "url": "https://api.example.com/mcp",
+                    "oauth": {
+                        "enabled": True,
+                        "token_url": "https://auth.example.com/oauth/token",
+                        "grant_type": "client_credentials",
+                        "client_id": "client-id",
+                        "client_secret": "client-secret",
+                    },
+                },
+                "no-oauth": {
+                    "enabled": True,
+                    "type": "http",
+                    "url": "https://example.com/mcp",
+                },
+            }
+        }
+    )
+
+    headers = asyncio.run(get_initial_oauth_headers(config))
+
+    assert headers == {"secure-http": "Bearer token-initial"}
+    assert len(post_calls) == 1
--- a/extensions_config.example.json
+++ b/extensions_config.example.json
@@ -32,7 +32,17 @@
        "headers": {                                                                                                                                           
          "Authorization": "Bearer $API_TOKEN",                                                                                                                
          "X-Custom-Header": "value"                                                                                                                           
-        }                                                                                                                                                      
+        },
+        "oauth": {
+          "enabled": true,
+          "token_url": "https://auth.example.com/oauth/token",
+          "grant_type": "client_credentials",
+          "client_id": "$MCP_OAUTH_CLIENT_ID",
+          "client_secret": "$MCP_OAUTH_CLIENT_SECRET",
+          "scope": "mcp.read mcp.write",
+          "audience": "https://api.example.com",
+          "refresh_skew_seconds": 60
+        }
    },
    "my-http-server": {                                                                                                                                       
        "type": "http",                                                                                                                                         
@@ -40,7 +50,14 @@
        "headers": {                                                                                                                                           
          "Authorization": "Bearer $API_TOKEN",                                                                                                                
          "X-Custom-Header": "value"                                                                                                                           
-        }                                                                                                                                                      
+        },
+        "oauth": {
+          "enabled": true,
+          "token_url": "https://auth.example.com/oauth/token",
+          "grant_type": "client_credentials",
+          "client_id": "$MCP_OAUTH_CLIENT_ID",
+          "client_secret": "$MCP_OAUTH_CLIENT_SECRET"
+        }
    }  
  },
  "skills": {