"spawn npx ENOENT spawn npx ENOENT" Error in Cline VSCode MCP Server Connection

Question

I tried to install OpenRouter MCP Server using Cline Extension in VSCode Insiders as MCP Client. I got my reference from Smithery (https://smithery.ai/server/@mcpserver/openrouterai).

This is my cline_mcp_settings.json located at "C:\Users\takan\AppData\Roaming\Code\User\globalStorage\saoudrizwan.claude-dev\settings":

{
  "mcpServers": {
    "openrouterai": {
      "command": "npx",
      "args": ["-y", "@smithery/cli@latest", "run", "@mcpserver/openrouterai"],
      "env": {
        "OPENROUTER_API_KEY": "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx",
        "OPENROUTER_DEFAULT_MODEL": "google/gemini-2.0-pro-exp-02-05:free"
      }
    }
  }
}

I got "spawn npx ENOENT spawn npx ENOENT" after Cline automatically connected with the server after I saved the file.

screenshot of the Cline extension tab

Answer 1

Update your configuration file with this:

    {
  "mcpServers": {
    "openrouterai": {
      "command": "cmd",
      "args": [
        "/c",
        "npx",
        "-y",
        "@smithery/cli@latest",
        "run",
        "@mcpserver/openrouterai"
      ],
      "env": {
        "OPENROUTER_API_KEY": "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx",
        "OPENROUTER_DEFAULT_MODEL": "google/gemini-2.0-pro-exp-02-05:free"
      }
    }
  }
}

Answer 2

I use both of wsl2 and macos. Meanwhile, I use fnm for managing nodejs version. I met this problem on both systems. And I think I figure out the reason and solution. No matter you use cline or Cursor. Connect MCP Servers error"spawn npx enoent" means mcp client can't correctly find npx command in your system. So if you're using fnm, don't use which npx to set npx path directly. This path is temporarily created by fnm so it'll outdate when restart device. The right way is to find to your fnm directory by command which fnm. For example, mine is /Users/CHJ/.local/state/fnm_multishells/32996_1746258653075/bin/npx. Then access to /Users/CHJ/.local/share/fnm/node-version/<select a version you want to use>/installation/bin/, you should be able to see npx file. To my understanding, fnm create temporary folder based on these nodejs versions under /Users/CHJ/.local/share/fnm/. Whatever, find the npx file that is constant and permanent. Then use this path alternate the npx in every mcp setting json. For example, in wsl2 using context7 mcp server by Cursor:

{
  "mcpServers": {
    "context7": {
      "command": "wsl",
      "args": [
        "bash",
        "-c",
        "'/Users/CHJ/.local/share/fnm/node-versions/v22.15.0/installation/bin/npx -y @upstash/context7-mcp@latest'"
      ],
      "enabled": true
    }
  }
}

in macos using context7 mcp server by Cursor:

{
  "mcpServers": {
        "context7": {
            "command": "/Users/CHJ/.local/share/fnm/node-versions/v22.15.0/installation/bin/npx",
            "args": [
                "-y",
                "@upstash/context7-mcp@latest"
            ]
        }
  }
}

Hope it can help you.