Client closed or No tools available in Cursor for Supabase MCP

[Kamciooo1226]

Bug report

Describe the bug

I think that last update broke the MCP Server. I cannot connect to the server. Yesterday everything was working, today I get client closed or No tools available in Cursor.

To Reproduce

Steps to reproduce the behavior, please provide code snippets or a repository:

1. Configure mcp.json in Cursor
2. Enable Supabase MCP connection.
3. Try to refresh the MCP connection.
4. See error "Client closed" or "No tools available"

Expected behavior

MCP connection and tools working properly.

Screenshots

System information

• OS: [Windows]
• Browser (if applies) N/A
• Version of supabase-js: [2.39.1]
• Version of Node.js: [v22.14.0]

Additional context

Add any other context about the problem here.

[Kamciooo1226]

UPDATE: deleting @latest from @supabase/mcp-server-supabase@latest fixes it so it definitely is an issue with the latest version.

[robboerman]

I confirm, fixing at 0.3.6 works, 0.4.0 seems broken, tool discovery does not work anymore

[MariusWilsch]

Same if you are using claude desktop

[janss-en]

not working on claude desktop for me even with @0.3.6, which, this version still works in Cursor/Windsurf, Cline, etc.

[risesightdeem]

MCP is not working when even following the steps from the guide. Same issue except I cant connect to the server at all.

[wuuJiawei]

Same here, I still can't use it on Cursor — even after removing @latest, it still shows "0 tools enabled."

[wuuJiawei]

Same here, I still can't use it on Cursor — even after removing @latest, it still shows "0 tools enabled."

I solved this problem by simply specifying the path to npx. Since I use nvm to manage npm versions locally, although I specified the version with nvm default 20, it doesn't take effect in Cursor. When I specified the npx version in mcp.json, the problem was resolved. Here's my configuration:

"supabase": {
  "command": "/Users/nobody/.nvm/versions/node/v20.19.0/bin/npx",
  "args": [
    "-y",
    "@supabase/mcp-server-supabase@latest",
    "--access-token",
    "sbp_xxx"
  ]
}

Additionally, your Node.js version must be 18 or above.

[papadok24]

NPX clear cache fixed my issue

[iamzeid]

NPX clear cache fixed my issue

Same. Clearing npx cache (and then restating Cursor) is exactly what worked for me.

The command I used:

npx clear-npx-cache