Claude Desktop Web Connector / Protected FastMCP server

[michela]

Hi all

Has anyone had protected MCP server compatibility with Claude.AI break this week? I was able to (painfully) setup the Oauth2 MCP flow on Sunday but sometime this week without any changes my end - I can no longer Connect from Claude.AI although MCP Inspector seems happy.

With a Bearer token issued from MCP Inspector - I am able to get Claude Desktop to accept a local proxy to the very same MCP server and use the tools that way but the streamlined UX to connect to and authenticated against my MPC server as a user friendly "Web Connector" is broken.

Not sure how to proceed with this error generated when I try to reconnect to my MCP service.

https://claude.ai/api/organizations/69ccca04-e2b0-40a3-85e8-48fcbd23b0b4/mcp/start-auth/b7943020-5f80-44f4-be54-4572f78896e4?redirect_url=claude%3A%2F%2Fclaude.ai%2Fnew%3F&open_in_browser=1&fromDesktopApp=true

{
  "type": "error",
  "error": {
    "type": "not_found_error",
    "message": "not_available"
  }
}

[michela]

Working again this week without any code change.

No Anthropic human support - just AI response followed by AI feedback bot...