How to Connect an MCP Server to Claude Code

The Model Context Protocol (MCP) lets Claude Code talk to external tools through a small server: a database connector, a browser, a docs index, and more. Once a server is connected, its tools appear to the agent automatically. This guide adds one with the CLI and confirms it works.

What you need

• Claude Code installed
• The command or URL for an MCP server you want to add
• Any credentials that server needs (as environment variables)
• About 10 minutes

Step 1: Add the server

Use claude mcp add to register a server. Below adds a filesystem server that runs over stdio. The double dash separates Claude's flags from the server's own command.

Step 2: Pass any required secrets

Servers that need a token take it via an environment variable. Use the --env flag so the value is stored in config, not pasted into chat.

claude mcp add github \
  --env GITHUB_TOKEN=ghp_yourtokenhere \
  -- npx -y @modelcontextprotocol/server-github

Step 3: Verify the connection

List your servers to confirm the status is connected. If it shows failed, the server command or a credential is wrong.

Step 4: Use the new tools

Start a session and run /mcp to see the tools the server exposes, then ask for something that needs them. The agent will call the server when relevant.

Result: Claude Code now has new capabilities beyond editing files, and you can add more servers the same way to wire it into the tools you already use.