MCP servers for Claude Desktop

How to add an MCP server to Claude Desktop

1. Open Claude Desktop → Settings → Developer → Edit Config. This creates claude_desktop_config.json if it does not exist yet.
2. Add the server under "mcpServers" with its command, args and any environment variables it needs.
3. Save, then fully quit and reopen Claude Desktop. Servers are only started on launch.
4. In a new chat, click the tools icon in the composer to confirm the server and its tools are listed.

{
  "mcpServers": {
    "filesystem": {
      "command": "npx",
      "args": ["-y", "@modelcontextprotocol/server-filesystem", "/Users/you/projects"]
    }
  }
}

The example uses the reference filesystem server. Every listing on mcp.site shows its own command, args and environment variables, usually with a ready-made snippet for Claude Desktop.

Hosted servers. Hosted servers do not go in the config file. Open Settings → Connectors → Add custom connector, paste the server's URL and complete the sign-in prompt. Custom connectors are available on paid Claude plans.

Node.js must be installed for npx-based servers. Claude Desktop uses the system PATH, so a server that runs fine in your terminal can still fail; if it does, use the absolute path to npx or node in "command".

Config formats change between releases. If a step looks different in your version, the Anthropic documentation ↗ is the source of truth.