Where does the bug appear (feature/product)? Cursor IDE Describe the Bug I am reporting a regression/incompatibility in how Cursor handles MCP servers hosted behind an API Gateway (GCP Apigee). While the connection works perfectly in Kiro, Cursor fails to establish the connection, resulting in a pe…

Thanks for the report @Sanjesh_Malviya ! This is a known issue we’re tracking. When Cursor connects to a remote MCP server, it probes for OAuth discovery metadata (e.g. .well-known endpoints). If the server (or an API gateway/proxy in front of it) returns a non-JSON response to those probes (e.g., a…

We ran into this 404 issue as well in the course of finding a couple of the bugs that Colin referenced. Cursor should handle HTML 404 and other error pages gracefully during discovery. Our workaround is to return JSON errors for specific resources that Cursor probes (e.g. /.well-known/oauth-protec…

When I configure Figma MCP server using direct URL (non-proxy URL) then it works Direct URL: https://mcp.figma.com/mc This MCP uses Oauth (username and password on browser) Cursor UI shows button ‘Connect’ that open the Browser and then user enter the username and password. Config: “figma”: { …

@Colin @rsb did any of your client configure Figma MCP sever using PROXY for Cursor.. how should we proceed for this Figma use case?

Sorry @Sanjesh_Malviya , I haven’t had any experience with Figma. Perhaps the proxy is stripping headers or other information?

[image] rsb: I haven’t h The same proxy-based Figma MCP setup is working successfully with AWS Kiro; however, it is not working with Cursor. Our team is trying to use the Figma MCP server via Cursor, but due to this issue, they are currently blocked and unable to proceed. Any help or guidan…

Hey @Sanjesh_Malviya , We’ve shipped a lot of improvements to MCP recently. Could you please try on v3.2 and let us know where things stand? cc @rsb

Subject: Figma MCP Server (SSE) Fails with 404/JSON Error in Cursor (Works in Kiro)

Support Bug Reports

Colin (Colin) April 13, 2026, 5:37pm 16

Hey @Sanjesh_Malviya!

This seems linked to a known bug that’s in progress, and hopefully we’ll have a resolution soon.

Other users (in other threads) have also chimed in with their discoveries, and some have been able to workaround it themselves.

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Subject: Figma MCP Server (SSE) Fails with 404/JSON Error in Cursor (Works in Kiro)

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