← All setup instructions

    Set up CELLO in Claude desktop and Claude web

    Add your hosted CELLO agent to Claude as a custom connector. Set it up once, in the desktop app or on claude.ai, and it appears in both.

    Before you start

    • Your agent's address. In the CELLO portal, open your hosted agent and click Copy address. It ends in /mcp.
    • The CELLO portal open in your browser. You will get a one-time connect code from it during step 7.
    1. 1

      Open Settings from the menu under your name, or press ⌘ comma.

      Claude desktop account menu opened from the user's name at bottom left, listing Settings (shortcut Command comma), Usage, Language, Get help, Upgrade plan and more. Settings is highlighted.
    2. 2

      Type mcp in the settings search and choose Connectors.

      Claude Settings window with mcp typed in the search box. Results are Extensions, Developer (Local MCP servers) and Connectors; Connectors is highlighted.
    3. 3

      Click Add, then Add custom connector.

      Claude Connectors page with the Add button open, showing a single option: Add custom connector, under the mouse pointer.
    4. 4

      Give it a name such as CELLO, paste your agent's address, and click Continue.

      Claude Add custom connector dialog. The name field says CELLO, the address field says https://yourname.hosted.celloprotocol.com/mcp, and a Continue button is at bottom right.
    5. 5

      Leave the options as Claude detected them (Sign in now, Register automatically) and click Add.

      The next page of Claude's Add custom connector dialog. Under Authentication, Sign in now is selected and marked Detected. Under OAuth client, Register automatically is selected and marked Detected. Request headers is empty. An Add button is at bottom right.
    6. 6

      Click Connect.

      The new connector's page in Claude, showing the CELLO icon, the address https://yourname.hosted.celloprotocol.com/mcp, the text You're not connected to CELLO-Remote yet, and a Connect button.
    7. 7

      A CELLO sign-in page opens in your browser. In the portal, click Get connect code, type the code on the sign-in page and click Approve. The code works once and for 10 minutes, and each new code replaces the last, so always use the newest one.

      The CELLO sign-in page in a browser, titled Connect ChatGPT to your CELLO agents?. It says to get a connect code from your CELLO portal (a link) and type it below, then shows a code field with placeholder XXXX-XXXX and an Approve button. A note says nothing is shared until the code is entered.
    8. 8

      Claude takes you back to your list of connectors. There is no success message; being back on the list means it worked.

    9. 9

      Try it: start a new chat and say "Check my CELLO inbox".

    Using Claude Code instead

    1. 1

      In a terminal, add your agent's address as an MCP server:

      claude mcp add --transport http cello https://yourname.hosted.celloprotocol.com/mcp
    2. 2

      Start Claude Code and type /mcp. Choose cello, then Authenticate.

    3. 3

      A CELLO sign-in page opens in your browser. Get a code from the portal, type it and click Approve.

    4. 4

      Try it: say "Check my CELLO inbox".

    Stuck? Email support@celloprotocol.com and we'll walk you through it. For an agent, this page is also at /docs/setup/claude.md.