When calling the Airtable MCP server (https://mcp.airtable.com/mcp) over Streamable HTTP with OAuth 2.0, the tool calls list_workspaces and list_bases succeed (isError = false), but the CallToolResult carries the payload only in structuredContent. The standard content array is returned empty.
What I observe:
- list_workspaces: content is empty, while structuredContent contains the actual workspaces.
- list_bases: content is empty, while structuredContent contains the actual bases.
- The OAuth access token is valid; the calls are not errors.
Why this is a problem: per the MCP spec, when a tool returns structuredContent it should also return a functionally-equivalent text block in the content array (a serialized/text form of the same result), for backward compatibility. Any MCP client or model that reads the standard content array sees nothing and concludes the tool returned an empty result, even though the workspaces/bases were actually returned in structuredContent.
Request: please also populate the content (text) array for tools like list_workspaces and list_bases (for example a JSON or text serialization of the same result), not only structuredContent. This keeps the Airtable MCP server compatible with clients that consume the standard text content.