Merge pull request #22750 from BerriAI/litellm_mcp_doc_update

[Chore] update mcp documentation for header forwarding

docs/my-website/docs/mcp.md

@@ -704,6 +704,63 @@ asyncio.run(main())
 
 [Learn more about customer management →](./proxy/customers)
 
+## Calling the Proxy's /v1/responses Endpoint
+
+When calling your LiteLLM Proxy's `/v1/responses` endpoint to use MCP tools, **always use `server_url: "litellm_proxy"`** in the tools array. This tells the proxy to use its configured MCP servers.
+
+:::important Do not use the full proxy URL
+Using `server_url: "https://your-proxy.com/mcp"` is incorrect when the request is already going to the proxy. The proxy needs the literal value `litellm_proxy` to route to its configured MCP servers.
+:::
+
+```bash title="Correct: Using litellm_proxy" showLineNumbers
+curl --location 'https://your-proxy.com/v1/responses' \
+--header 'Content-Type: application/json' \
+--header "Authorization: Bearer $LITELLM_API_KEY" \
+--data '{
+    "model": "gpt-4",
+    "tools": [
+        {
+            "type": "mcp",
+            "server_label": "litellm",
+            "server_url": "litellm_proxy",
+            "require_approval": "never"
+        }
+    ],
+    "input": "Run available tools",
+    "tool_choice": "required"
+}'
+```
+
+### Sending Custom Headers to MCP Servers
+
+To pass custom headers (e.g., API keys, auth tokens) to specific MCP servers, use either:
+
+**Option 1: Request headers** – Add `x-mcp-{server_alias}-{header_name}` to your request headers. The proxy forwards these to the matching MCP server.
+
+```bash
+# Send Authorization header to the "weather2" MCP server
+--header 'x-mcp-weather2-authorization: Bearer your-token'
+
+# Send custom header to the "github" MCP server  
+--header 'x-mcp-github-x-api-key: your-api-key'
+```
+
+**Option 2: Headers in tool config** – Include a `headers` object in the tool definition. These are merged with request headers.
+
+```json
+{
+    "type": "mcp",
+    "server_label": "litellm",
+    "server_url": "litellm_proxy",
+    "require_approval": "never",
+    "headers": {
+        "x-litellm-api-key": "Bearer YOUR_LITELLM_API_KEY",
+        "x-mcp-servers": "Zapier_MCP,dev-group",
+        "x-mcp-weather2-authorization": "Bearer your-weather-api-token"
+    }
+}
+```
+
 ## Using your MCP with client side credentials
 
 Use this if you want to pass a client side authentication token to LiteLLM to then pass to your MCP to auth to your MCP.

docs/my-website/docs/mcp_control.md

@@ -323,7 +323,7 @@ curl --location '<your-litellm-proxy-base-url>/v1/responses' \
         {
             "type": "mcp",
             "server_label": "litellm",
-            "server_url": "<your-litellm-proxy-base-url>/dev_group/mcp",
+            "server_url": "litellm_proxy",
             "require_approval": "never",
             "headers": {
                 "x-litellm-api-key": "Bearer YOUR_LITELLM_API_KEY"
@@ -335,7 +335,7 @@ curl --location '<your-litellm-proxy-base-url>/v1/responses' \
 }'
 ```
 
-This example uses URL namespacing to access all servers in the "dev_group" access group.
+This example uses the `x-mcp-servers` header to access all servers in the "dev_group" access group. Use `server_url: "litellm_proxy"` when calling the proxy's `/v1/responses` endpoint—do not use the full proxy URL.
 
 </TabItem>
 
@@ -423,7 +423,7 @@ curl --location '<your-litellm-proxy-base-url>/v1/responses' \
         {
             "type": "mcp",
             "server_label": "litellm",
-            "server_url": "<your-litellm-proxy-base-url>/mcp/",
+            "server_url": "litellm_proxy",
             "require_approval": "never",
             "headers": {
                 "x-litellm-api-key": "Bearer YOUR_LITELLM_API_KEY",
@@ -436,7 +436,7 @@ curl --location '<your-litellm-proxy-base-url>/v1/responses' \
 }'
 ```
 
-This configuration restricts the request to only use tools from the specified MCP servers.
+This configuration restricts the request to only use tools from the specified MCP servers. Use `server_url: "litellm_proxy"` when calling the proxy's `/v1/responses` endpoint.
 
 </TabItem>
 

ui/litellm-dashboard/src/components/mcp_tools/mcp_connect.tsx

@@ -256,7 +256,7 @@ const MCPConnect: React.FC<MCPConnectProps> = ({ currentServerAccessGroups = []
         {
             "type": "mcp",
             "server_label": "litellm",
-            "server_url": "${proxyBaseUrl}/mcp",
+            "server_url": "litellm_proxy",
             "require_approval": "never",
             "headers": {
                 "x-litellm-api-key": "Bearer YOUR_LITELLM_VIRTUAL_KEY",