TLDR:
1 solution to this problem is to make sure the path where you install the server doesn’t contain spaces.
e.g:
node C:/my projects/mcpserver/build/index.js will fail because of a space in “my projects”
node C:/projects/mcpserver/build/index.js will work as there are no spaces
notes:
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I’m on windows 11 and I’ve tried forward and backslashes and they both work. I just tried forward slashes first, so copying the path of the index.js file in the build folder also works.
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I run nvm and I’ve also tried running the server global with spaces in the path and that also didn’t work, with or without full paths to node.exe and the index.js file and with or without quotes around the full paths - Getting rid of spaces in the path was my solution.
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You don’t need to run the server manually before adding the command - the command will start the server automatically - just in case you weren’t sure. You should, however, first try to start and stop the server manually before adding it to cursor so you know the server starts without errors.
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This isn’t the only possible cause or solution - I’m sure there are other reasons why it may fail to find tools.
How I found out:
In my case I had:
D:\My Data\Projects.…
When I tried adding (or refreshing) any MCP server that’s installed in a subdirectory in the path above I briefly see a terminal flashing and a node executable being added and removed to the task manager. I wanted to know what is going on and used the free sysinternals ProcessMonitor tool to check what cursor is trying to execute.
I set the command in the add MCP server without quotes around the path and got this when I refreshed the server:
(Still not allowed to upload multiple images in 1 post so had to post a screenshot of the edit screen which makes it hard to read…)
