Document client credentials grant for MCP authentication

ai/model-context-protocol.mdx

@@ -38,7 +38,7 @@
 The MCP search tool supports optional parameters that AI applications use to control and refine search results.
 
 - **`pageSize`**: Number of results to return, between 1 and 50. Defaults to 10.
 - **`scoreThreshold`**: Minimum relevance score between 0 and 1. Only returns results at or above this threshold. Use this to filter out low-relevance matches.
 - **`version`**: Filter results to a specific documentation version. For example, `'v0.7'`. Only returns content tagged with the specified version or content available across all versions.
 - **`language`**: Filter results to a specific language code. For example, `'en'`, `'zh'`, or `'es'`. Only returns content in the specified language or content available across all languages.
 
@@ -104,6 +104,49 @@
   </Step>
 </Steps>
 
+### Client credentials for server-to-server access
+
+If you need to connect to an authenticated MCP server from an automated system, CI/CD pipeline, or backend service, you can use the OAuth 2.0 `client_credentials` grant type instead of the interactive browser-based flow.
+
+The `client_credentials` grant authenticates using a client ID and client secret, so no user interaction is required. This is useful when an application needs to access your MCP server programmatically without a browser.
+
+To authenticate with client credentials, send a `POST` request to your MCP server's token endpoint with the `client_credentials` grant type. You can provide the client ID and secret as form parameters or with an HTTP Basic `Authorization` header.
+
+<Tabs>
+<Tab title="Form parameters">
+
+```bash
+curl -X POST https://your-docs-site.com/mcp/oauth/token \
+  -d "grant_type=client_credentials" \
+  -d "client_id=YOUR_CLIENT_ID" \
+  -d "client_secret=YOUR_CLIENT_SECRET"
+```
+
+</Tab>
+<Tab title="Authorization header">
+
+```bash
+curl -X POST https://your-docs-site.com/mcp/oauth/token \
+  -d "grant_type=client_credentials" \
+  -H "Authorization: Basic $(echo -n 'YOUR_CLIENT_ID:YOUR_CLIENT_SECRET' | base64)"
+```
+
+</Tab>
+</Tabs>
+
+A successful response returns an access token:
+
+```json
+{
+  "access_token": "eyJhbGci...",
+  "token_type": "Bearer",
+  "expires_in": 1209600,
+  "scope": "mcp:search"
+}
+```
+
+Client credentials tokens are subject to server-side revocation checks. If a credential is revoked in the dashboard, any tokens issued with that credential stop working immediately. This does not affect tokens issued through the interactive authorization code flow.
+
 ### Rate limits
 
 To protect availability, Mintlify applies rate limits to MCP servers.