Connecting MCP Servers to Claude Desktop and Claude Code

Once you have an MCP server, connect it to a host app so the model can use it. Here's how to do that in two popular hosts.

Claude Desktop

Open Settings, then Developer, then Edit Config. This opens claude_desktop_config.json. Add your server under mcpServers:

{
  "mcpServers": {
    "github-info": {
      "command": "node",
      "args": ["/Users/you/projects/github-mcp/build/index.js"]
    },
    "notes": {
      "command": "uv",
      "args": ["--directory", "/Users/you/projects/notes-mcp", "run", "server.py"],
      "env": { "NOTES_DB": "/Users/you/notes.db" }
    }
  }
}

Restart Claude Desktop. Use absolute paths; the app doesn't start servers from your project directory.

Claude Code

# Local stdio server: everything after -- is the command to run
claude mcp add github-info -- node /Users/you/projects/github-mcp/build/index.js

# With environment variables
claude mcp add notes -e NOTES_DB=/Users/you/notes.db -- uv --directory /Users/you/projects/notes-mcp run server.py

# Remote server over HTTP
claude mcp add --transport http docs https://mcp.example.com/mcp

claude mcp list

Sharing servers with your team

Claude Code can store servers in a project-level .mcp.json file that you commit, so everyone working in the repo gets the same tools. Keep secrets out of it; reference environment variables instead.

{
  "mcpServers": {
    "postgres": {
      "command": "npx",
      "args": ["-y", "some-postgres-mcp-server"],
      "env": { "DATABASE_URL": "${DATABASE_URL}" }
    }
  }
}

Troubleshooting

• Server not showing? Run the exact command in a terminal to see if it crashes.
• Check the host's MCP logs for stderr output from your server.
• A server that prints to stdout will break the connection.
• Only install servers you trust; they run with your user's permissions.