Debug Mode does not support MCP

Support Bug Reports
1

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

When running Cursor in Debug Mode, features that rely on MCP (Model Context Protocol) do not function. MCP-dependent actions either fail silently or are unavailable while Debug Mode is active. The same MCP features work as expected outside of Debug Mode.

Steps to Reproduce

Open Cursor.

Enable or configure MCP (Model Context Protocol).

Open a project that uses MCP-dependent functionality.

Start Debug Mode.

Attempt to use any MCP-based feature or workflow.

Expected Behavior

MCP should be supported and function correctly in Debug Mode, or Debug Mode should clearly indicate that MCP is unsupported.

Operating System

MacOS

Current Cursor Version (Menu → About Cursor → Copy)

Version: 2.3.21 (Universal)
VSCode Version: 1.105.1
Commit: 68e0a0385b87408d050869ea543e3778ad53f780
Date: 2026-01-02T23:46:13.381Z
Electron: 37.7.0
Chromium: 138.0.7204.251
Node.js: 22.20.0
V8: 13.8.258.32-electron.0
OS: Darwin arm64 25.1.0

For AI issues: which model did you use?

Opus 4.5

Does this stop you from using Cursor

No - Cursor works, but with this issue

2

Can you specify what do you mean by debug mode? is it debug chat mode? or is it debugging in which you can step through the code? or something else?

3

Hey, can you clarify what you mean by “Debug Mode”? Is it:

  1. Debug Chat Mode (the mode toggle in chat)
  2. The VS Code debugger (when you debug code using breakpoints)
  3. Something else?

A similar issue is described here: Debug mode dont work with MCP's. That one is about Debug Chat Mode in chat.

If this is about Debug Chat Mode, can you share:

  • A screenshot of Cursor Settings > Tools & MCP (so we can see the MCP servers show a green status)
  • Which MCP servers exactly don’t work in Debug Mode?
  • The Request ID (Chat context menu > Copy Request ID), if you can turn off Privacy Mode

That should help us figure out what exactly isn’t working.

4

Yup, its the debug chat mode. Here is the same question with agent and debug mode.
it seems to be a duplicate of the issue you have pointed out above. I cannot share request ID due to our privacy mode settings.

Screenshot 2026-01-20 at 10.00.58 AM
Screenshot 2026-01-20 at 10.00.58 AM361×350 6.61 KB

Screenshot 2026-01-20 at 10.00.41 AM
Screenshot 2026-01-20 at 10.00.41 AM361×350 23.8 KB

5

you can see the output from list_issues tool call by clicking the two arrows on the right, check the output

6

sorry the top image is agent mode the bottom one is debug mode

7

Hey, I see screenshots from Agent Mode and Debug Mode. This looks like a known issue.

The team is already aware of it. A few users have reported that MCP tools work in Agent Mode, but aren’t recognized in Debug Chat Mode.

Could you share a bit more info:

  1. A screenshot of Cursor Settings > Tools & MCP (so we can see the green server status indicators)
  2. Does this happen only with this MCP, or are other ones unavailable too?
  3. In Debug Mode, try requesting the list of available MCP servers

This will help the team understand what’s failing specifically in Debug Mode.

8

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