diff --git a/README.md b/README.md index aa8f9304c..de297dc9f 100644 --- a/README.md +++ b/README.md @@ -500,6 +500,21 @@ app.delete('/mcp', handleSessionRequest); app.listen(3000); ``` +> [!TIP] +> When using this in a remote environment, make sure to allow the header parameter `mcp-session-id` in CORS. Otherwise, it may result in a `Bad Request: No valid session ID provided` error. +> +> For example, in Node.js you can configure it like this: +> +> ```ts +> app.use( +> cors({ +> origin: ['https://your-remote-domain.com, https://your-other-remote-domain.com'], +> exposedHeaders: ['mcp-session-id'], +> allowedHeaders: ['Content-Type', 'mcp-session-id'], +> }) +> ); +> ``` + #### Without Session Management (Stateless) For simpler use cases where session management isn't needed: