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Moonjar Help

Connect external MCP servers to chat

The chat assistant has a lot of built-in tools, but you can add more. Any MCP-compatible server can be plugged into Moonjar’s chat — the assistant sees the new tools and can call them in any conversation. This is the outbound direction: your Moonjar chat reaching out to other services. (For the inbound direction — external Claude clients reaching into Moonjar — see Connect Moonjar to Claude.)

Before you start

Section titled “Before you start”
  • The MCP server’s URL.
  • Any authentication the server needs — an API key (passed as a header) or OAuth credentials (Moonjar runs the OAuth dance for you).

Steps

Section titled “Steps”
  1. Open Moonjar.
  2. Go to Settings → MCP servers (or the MCP servers screen under More) — [TODO: VERIFY exact path].
  3. Tap Add.
  4. Fill in:
    • Name — a short identifier. Lowercase, alphanumeric, hyphens or underscores; up to 40 characters. The chat assistant uses this name to namespace the server’s tools so they don’t collide with built-ins.
    • Display name — what the server is called in the UI.
    • URL — the MCP endpoint.
    • API key (optional) — if the server needs a static key, enter it here.
    • Headers (optional) — custom HTTP headers the server needs.
  5. Save. Moonjar tries to discover the server’s tools by handshaking with it.
  6. If the server supports OAuth (rather than a static key), Moonjar shows Authenticate — tap it, sign in to the third-party service, return to Moonjar. The token comes back through Moonjar’s OAuth callback and is stored against the server.

After tools are discovered, they appear in the chat assistant’s tool surface alongside the built-ins. The assistant uses them when relevant; you don’t have to invoke them by name.

Test a connection

Section titled “Test a connection”

From the server’s detail screen, tap Test connection. Moonjar re-runs tool discovery and reports the result — if the server is reachable, how many tools were found, and any error.

Edit or remove

Section titled “Edit or remove”
  • Edit — change the URL, key, headers, or display name.
  • Disable — keep the server registered but stop the assistant from seeing its tools.
  • Reset OAuth — drop the stored token and re-authenticate from scratch.
  • Delete — remove the server entirely. Tools disappear from the assistant’s surface immediately.

Limits

Section titled “Limits”
  • Maximum number of MCP servers per account is bounded ([TODO: VERIFY exact cap from MAX_SERVERS_PER_USER]). The picker shows the limit when you hit it.
  • Server name must be 1–40 lowercase characters, hyphens, or underscores.
  • The MCP URL must be HTTPS (or localhost for development); other schemes are rejected.
  • An OAuth-protected server’s token is bound to one third-party account. To connect a different account, reset the OAuth and re-authenticate.

See also

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