Connect Claude Code to an external service
Add a real MCP endpoint, authenticate, and verify one read-only tool.
Choose a service you use and read its MCP documentation. A REST URL is not automatically an MCP server. This example uses the Notion endpoint shown in the official Claude Code docs; you need your own Notion account and permission to the chosen content.
1. Register the server
Run the command below from the intended project. By default this creates a local-scoped configuration for this project. Use --scope project only when you deliberately want a reviewed .mcp.json shared with the repository. Keep tokens out of committed configuration.
claude mcp add --transport http notion https://mcp.notion.com/mcp
claude mcp list
claude2. Authenticate and inspect the tools
Inside the Claude Code session, run /mcp. Follow the service sign-in flow if authentication is required, review the access requested, and confirm connection status. An “Added” message only means configuration was saved; it does not prove successful authentication.
/mcp3. Prove a small read-only request
Choose a page you are allowed to access. Ask for its title and a short summary with a source link. Confirm the tool name and returned content. Permission to read is different from permission to create or edit. Do not test a connection by making a destructive change.
Use the connected Notion tool to read the page I specify.
Return its title, three factual bullets, and its URL.
Do not create, edit, or delete anything.4. Diagnose or remove the connection
A 401 usually points to authentication; a 403 to access or policy; no tools may mean a wrong endpoint or disabled integration. Check /mcp and server logs, then the service documentation. Remove an unused connection with the same scope you used to add it.
claude mcp get notion
claude mcp remove notionPractice & self-check
Connect one service, verify a read-only result against its original page, then identify how you would disconnect it.
When you’re done, take a moment to check:
Read the official sources
CLI instructions checked against official documentation; API examples tested with simulated responses. Product-account walkthroughs were not performed.