Magnific MCP returns "400 Client not found" in Open Design

[ErkanDoman]

Hi 👋

I'm trying to connect Magnific MCP to Open Design.

Current setup:

• MCP URL:
  https://mcp.magnific.com/mcp

• OpenID metadata loads correctly:
  https://auth.magnific.com/realms/mcp/.well-known/openid-configuration

• Local proxy also tested successfully.

OAuth flow starts, but after redirect Magnific returns:

400 — Client not found

It looks like Open Design's OAuth client ID is not accepted by Magnific.

Has anyone successfully connected Magnific MCP to Open Design yet?

Thanks 🙏

[samay-hash]

Hi @ErkanDoman
The 400 — Client not found error during the OAuth flow specifically means that Magnific's authorization server does not recognize the client_id being sent by Open Design.
If you are just providing the MCP URL and Open Design is sending its default Client ID, it will fail until Magnific adds us to their recognized clients list.
Do you know if Magnific provides a way for users to generate their own ouuth credentials? If not, we might need to reach out to the Magnific team to get Open Design officially whitelisted! Let me know if you have any contacts there.