[Bug] Generated Claude Desktop config doesn't work (v9.4.6, Windows, Stdio)

[wyrdweir]

The MCP config generated by the MCP For Unity editor window for Claude Desktop does not result in a working connection. Following the provided Manual Configuration Installation Steps (copy config JSON, paste into claude_desktop_config.json, restart Claude Desktop) results in Unity MCP tools not appearing in Claude Desktop.

Steps to Reproduce
-Open MCP For Unity window (v9.4.6)
-Select "Claude Desktop" as the client
-Expand "Manual Configuration"
-Follow the Installation Steps - copy the generated JSON, paste into claude_desktop_config.json, save, restart Claude Desktop
-Unity MCP tools do not appear in Claude Desktop

Generated Config (non-working)

{
  "mcpServers": {
    "unityMCP": {
      "command": "C:\\Users\\<user>\\.local\\bin\\uvx.exe",
      "args": [
        "--from",
        "mcpforunityserver==9.4.6",
        "mcp-for-unity",
        "--transport",
        "stdio"
      ]
    }
  }
}

Workaround
Configuring the MCP server manually through Claude Desktop's own UI (Settings > Developer > Local MCP servers) with uv --directory <extension-path> run windows-mcp works correctly.

Environment
MCP For Unity: v9.4.6
Platform: Windows 11
Transport: Stdio
Client: Claude Desktop

[dsarno]

I don't see this on my windows computer, everything works fine. Suggestions from Claude:

Recommended response to the reporter:

• Ask them to check Claude Desktop MCP logs at %APPDATA%\Claude\logs\ for the actual error from the server spawn.
• Ask them to verify uvx.exe exists at the path shown in the config by running it in a terminal: C:\Users\<user>\.local\bin\uvx.exe --version
• Ask them to manually test the full command in a terminal:

  C:\Users\<user>\.local\bin\uvx.exe --from mcpforunityserver==9.4.6 mcp-for-unity --transport stdio
  

  This will show the actual error (package not found, network issue, Python issue, etc.)
• If stale cache is suspected, suggest adding --no-cache --refresh to the args manually, or running uv cache clean first.

[dsarno]

Closing, can't reproduce, should work on most systems.