It’s all over the place. I uninstalled and reinstalled node.js globally, which seemed to help.
They all show as green and all of them show the available tools, with prompts when hovering. Yet, when I ask the agent, it can only see a small fraction of them. If it tries to use a tool that should work, it simply fails.
Until now, nothing on my end has changed other than Cursor updating.
Can it be the 40 tools limit? (severals MCPs exposed so many tools which polluted the context quicky)
Yeah otherwise best to provide for the Cursor team or other forum members who help with MCP bug report detalis, and as I see you helping others 
Wish it would be simpler!
I don’t think it’s the limit. I guess it would be close. I’ll try to remove a few in a bit and see if it helps. I’ve been running the same set for a few weeks, though. Not to say the MCP developers didn’t add more.
Yeah try just one. if that works then you are closer to the solution
Hello! Loyal cursor user here. I was wondering if you could respond to my thread under my profile. I have the most updated form of cursor. My mcp tools are recognized just never called. I cursed at the LLM and it managed to call it once.
Actually I’d appreciate if you can explain what went wrong and caused this glitch? So we can understand how cursor calls MCP server better. If that’s ok. 
Hey, I think @danperks can explain better what and how it works.
Hello, currently none of the mcp services are working. I am using Claude Sonnet 3.7 and latest version. @deanrie
In case anyone is still having this issue, I discovered my MCP server implementation was breaking due to the very non-standard way that Cursor handles tool names.
Specifically, Cursor seems to automatically transform kebab case names to snake case, for example list-sites becomes list_sites when the agent tries to call the tool. It then (of course) cannot find the tool with that snake cased name because it does not exist.
This is quite annoying, especially since the MCP TS SDK docs themselves promote a skewer case convention: GitHub - modelcontextprotocol/typescript-sdk at 592c91fc86607a7c11ec60da5a31e58396448cea
Changing the names of my tools to follow snake case convention seems to have solved the problem for me.
@deanrie @danperks perhaps something the team can look into?
Man this is awesome. I hope there is a patch soon. @stephencme thanks for your contribution!
will take a look. iirc some models choked on tools with hyphens in the name (among a million other things i had to sanitize) but i will see if i can loosen this up
Same here
Version: 0.48.7 (Universal)
VSCode Version: 1.96.2
Commit: 1d623c4cc1d3bb6e0fe4f1d5434b47b958b05870
Date: 2025-04-02T04:51:59.792Z
Electron: 34.3.4
Chromium: 132.0.6834.210
Node.js: 20.18.3
V8: 13.2.152.41-electron.0
OS: Darwin arm64 24.3.0
Try this:
Great, It works. But maybe it’s a bug of cursor’s mcp client? Because according to the official demo from mcp, the kebab-case should work
Doesn’t work for me. Still have issues with MCP tool that works in Augment Agent for example. Give -32602 error and Tool not found
The problem is not with the MCP server and doesn’t use kebab-case. Only snake_case
this is fixed in 49, rolling out this week
Is this out already?
