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Airtable MCP: list_workspaces fails with "Error POSTing to endpoint: FORBIDDEN"

Error: Streamable HTTP error: Error POSTing to endpoint: {"error":"FORBIDDEN","message":"Forbidden"}

What causes it

In our Oct 20, 2026 test of Airtable's MCP server (mcp.airtable.com/mcp) with a personal access token sent as a Bearer header, list_workspaces failed with this HTTP 403 on the POST itself. It did not come back as a normal tool error, so some clients report it as a connection failure. The same session kept working: 28 of 29 tasks passed, including list_bases, search_bases, record writes, revert_action and table create and delete. Our token was created for one test base. Airtable's MCP docs list workspacesAndBases:read among the scopes a PAT should have and let you add whole workspaces as token resources. We have not yet confirmed which of the two fixes this call.

How to fix it

  1. Open airtable.com/create/tokens and check that the token has the workspacesAndBases:read scope (Airtable lists it with the other MCP scopes).
  2. Under Access, add the workspace itself, not only individual bases, if your agent needs to list workspaces or create bases.
  3. If you only need data from known bases, skip list_workspaces: list_bases and search_bases return the base IDs every other tool needs, and they worked with our base-only token.
  4. Treat the 403 as a permission answer, not an outage. Other tools keep working in the same session, so retrying the connection will not help.

Where we hit it

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