Supabase MCP server fails silently on Windows with valid token and correct setup

[eliasrob]

Bug report

Describe the bug

The Supabase MCP server fails silently on Windows even when all setup steps are correct. No logs or errors are shown when running via npx, and Cursor IDE is unable to connect (shows “Failed to create client”).

To Reproduce

Steps:

1.Create a Supabase project and generate a Personal Access Token

2.Add this config to .cursor/mcp.json:

{
  "mcpServers": {
    "supabase": {
      "command": "cmd",
      "args": [
        "/c",
        "npx",
        "-y",
        "@supabase/mcp-server-supabase@latest",
        "--access-token",
        "sbp_xxxxxxxxxxxxxxxxxxxxxx",
        "--stdio"
      ]
    }
  }
}

3.Launch Cursor (from terminal with PATH set properly)

4.Observe failure in Settings → MCP (status remains red)

Also reproduced when running directly:

npx -y @supabase/mcp-server-supabase@latest --access-token sbp_xxxx --stdio --debug

Expected behavior

The MCP server should:

*Stay running when launched

*Print logs or errors when started

*Respond to Cursor with an active connection and tool list

Screenshots

No screenshots available, as MCP fails silently.

System information

OS: Windows 10 (Build 26100.3476)

Node.js version: 20.19.0 (via NVM)

Cursor version: Latest (as of April 6, 2025)

Supabase MCP Server: @supabase/mcp-server-supabase@latest

Supabase CLI login: Works

Supabase project: Exists and reachable

Token: Valid personal access token

Additional context

npm cache clean and full reinstall tested

Launching Cursor from terminal with correct PATH also tested

Tried both "npx" and "cmd" commands in mcp.json

Suspect MCP server has an unhandled error and exits without logging

May be related to dependency issues (postgres-meta, libpg-query, etc.)

Would love to see:

A verbose/force logging mode

A working Windows install or Docker option

OAuth-based connection support (per your roadmap)

[rdylina]

Same issue, but I do get the following log directly from my Cline MCP Dashboard.

npm warn deprecated @npmcli/[email protected]: This functionality has been moved to @npmcli/fs npm warn deprecated [email protected]: This module is not supported, and leaks memory. Do not use it. Check out lru-cache if you want a good and tested way to coalesce async requests by a key value, which is much more comprehensive and powerful. npm warn deprecated [email protected]: This package is no longer supported. npm warn deprecated [email protected]: This package is no longer supported. npm warn deprecated [email protected]: Rimraf versions prior to v4 are no longer supported npm warn deprecated [email protected]: Glob versions prior to v9 are no longer supported npm warn deprecated [email protected]: This package is no longer supported. npm warn deprecated [email protected]: This package is no longer supported. npm warn deprecated [email protected]: This package is no longer supported. npm warn deprecated [email protected]: This package is no longer supported. MCP error -32000: Connection closed

[spmcap]

+1. Same issue on same system with same log entries on Claude Desktop.

12 hours troubleshooting. No success,

Tried different Node Versions, Local Installation, Wrapper Scripts, WSL. As said, no success.

However, thank you for your work and effort 🙌👌

[GaryAustin1]

I had no problem with getting it going on Cursor and there is a thread now on Discord where I compared setups with a user who was not working and they eventually got theirs working.

Exactly which thing fixed it for them is unclear but towards the end of this Discord thread is the info: https://discord.com/channels/839993398554656828/1358144624824418364

One change was setting it up project specific. The other was turning off other MCP server except for Supabase. After making both changes it still works adding back the other servers. They also upgraded everything to latest versions.

[3N15]

i have this same bug. it happens when using the latest or 0.2.0 version.

when i use 0.1.0 it works.

seems to be a module resolution error with the MCP server package running into compatibility issue with Node.js v22.14.0, which is the latest version.

[eliasrob]

@GaryAustin1 i tried the steps mentioned in the discord thread but still couldn't get the MCP server running.
thanks tho