Claude Desktop
Connect Part3 to the Claude Desktop app.
Claude Desktop adds remote MCP servers like Part3 through the in-app
Connectors UI — not the claude_desktop_config.json file. (That file is
only for local stdio servers; Claude Desktop will not connect to a remote
server defined there.)
Add the Part3 connector
In Claude Desktop, go to Settings → Connectors and click Add custom connector at the bottom of the list.
Name: Part3. URL: https://mcp.part3.io. Leave the OAuth client ID /
secret (under Advanced settings) blank — Part3 handles auth
automatically. Click Add.
Claude opens a browser to the Part3 sign-in page. Sign in, approve the consent screen, and you're done.
No header, no secret. Claude Desktop discovers the OAuth endpoints automatically and opens the browser sign-in on first use.
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.
Verify
Open a chat, click the + button (lower-left of the message box), hover
Connectors, and confirm Part3 is listed and enabled. Then ask:
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.