CRITICAL BUG: Cursor routing tool calls to wrong MCP servers

Bug Reports
1

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

Tool calls that should go to a named server, are wrongly being sent to a server that appears earlier in the mcp.json file even though the complete tool name is different.

Steps to Reproduce

Run 2 MCP SSE servers, such that two different tools on each are named:
mcp_serverone_mytool
mcp_servertwo_mytool

calls to servertwo will always go to serverone by mistake

Expected Behavior

correct server should be used!

Note: This is a catastrophic mistake - in my case, I’m running root-level commands on multiple servers - the right command on the wrong server is devastating.

Screenshots / Screen Recordings

pic_2025-11-09_18.56.19_2293.png
pic_2025-11-09_18.56.19_2293.png1503Ă—570 42.5 KB

Operating System

Windows 10/11

Current Cursor Version (Menu → About Cursor → Copy)

Version: 2.0.60 (system setup)
VSCode Version: 1.99.3
Commit: c6d93c13f57509f77eb65783b28e75a857b74c00
Date: 2025-11-05T00:50:54.645Z
Electron: 37.7.0
Chromium: 138.0.7204.251
Node.js: 22.20.0
V8: 13.8.258.32-electron.0
OS: Windows_NT x64 10.0.17763

Additional Information

Should be an easy fix - looks like you’re storing the basic tool name someplace, instead of the canonical name with the server identity prefixed.
I copied your format for my own client - it’s an annoying problem, because you used “_” as the delimiter but then allow users to have _ in the name of the server, so there’s no easy way to tell how to split these back up once they’ve been concatenated. Lucky though, you don’t need to if you store the names in a DICT and throw an error if there’s a dupe.

Does this stop you from using Cursor

Yes - Cursor is unusable

2

Hey, thanks for the report. This is a critical issue, and I can confirm at least one other user is seeing the same: MCP Server Tool Collision (Airtable/Supabase MCP server collision).

Your analysis of the tool name storage issue looks accurate. I’ll escalate this to the team due to the severe impact (commands being routed to the wrong servers).

Temporary workarounds:

  • Run only one MCP server at a time, or
  • Rename servers to avoid similar tool name patterns

Let me know if you find any other workarounds.

4

I can confirm that the tool-rename workaround is good - in my case, I added _linux to the end of name of the tool on linux, and then Claude had no problems calling it.

If someone is working on MCP anyhow, this would be a low-hanging-fruit bug to fix at the same time:

1 Like
5

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