MCP
MCP connection problems
Fix the common reasons an AI client can't connect to Signal's MCP bridge: token, URL, or revocation.
Last updated June 14, 2026
Most MCP connection issues come down to the bearer token or the endpoint URL configured in your AI client. Work through the cases below before changing anything else in your setup.
Troubleshooting
- 401 / unauthorized from the bridge.
- The bearer token is missing, mistyped, or revoked. Create a fresh token in Settings → MCP → Tokens and update your client config.
- The client connects but sees no workspace data.
- The token is scoped to a different workspace than you expect. Create the token from the workspace whose data you want.
- 503 from the bridge.
- The server-side persistence isn't configured in that environment. This is an environment/config issue, not your token.