Scheduler Zero
MCP

Troubleshooting MCP

Resolve common connection, authentication, permission, and workspace errors.

The client opens a login flow unexpectedly

No bearer token reached the server. For a headless client, confirm that SCHEDULER_ZERO_API_KEY exists in the agent process and that the client sends it as Authorization: Bearer ....

401 Unauthorized

The credential is missing, invalid, expired, or revoked. OAuth clients should reconnect and complete sign-in again. API-key clients should create or select a valid sz_... key.

403 Forbidden

The credential is valid but lacks the permission required by the selected tool. Update the key's scopes or use a different key with the minimum necessary access.

The tools point at the wrong workspace

  • OAuth session: run whoami, then listWorkspaces and switchWorkspace.
  • API-key session: use a key created in the intended workspace. API-key sessions cannot switch workspaces.

A new REST operation is missing

Start a fresh MCP session. REST-backed tools are registered from the current OpenAPI contract when the session initializes.

Available tools

Learn how Scheduler Zero maps REST operations and session controls into MCP tools.

REST API

Programmatic access to campaigns, leads, inboxes, webhooks, and workspace data.

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The client opens a login flow unexpectedly401 Unauthorized403 ForbiddenThe tools point at the wrong workspaceA new REST operation is missing