Claude Desktop

Claude Desktop uses a JSON config file rather than a CLI. You'll add the Part3 MCP server as an entry in claude_desktop_config.json.

Locate the config file

OS	Path
macOS	`~/Library/Application Support/Claude/claude_desktop_config.json`
Windows	`%APPDATA%\Claude\claude_desktop_config.json`
Linux	`~/.config/Claude/claude_desktop_config.json`

If the file doesn't exist, create it with {} as the initial content.

Add the MCP server

{
  "mcpServers": {
    "part3": {
      "type": "url",
      "url": "https://mcp.part3.io"
    }
  }
}

No header, no secret. Claude Desktop discovers the OAuth endpoints automatically and opens a browser on first use to sign in and approve access.

Prime-only access

MCP is currently limited to users who are a Project Prime on at least one project, plus super-duper-admins. Non-Primes will see an access-denied page on the consent screen.

Restart Claude Desktop

Quit fully (Cmd/Ctrl + Q) and reopen. Click the plug icon in a chat window to confirm part3 is listed.

Claude Desktop loads MCP config at launch only. Any config change requires a full app restart.

Verify

Ask Claude:

Using Part3, list my active projects.

If Claude uses a Part3 tool and returns a list, the integration is working.

Troubleshooting

See the Claude Code troubleshooting section — the same causes and fixes apply to Claude Desktop.