The system cannot find the file specified" error when mcp-cli calls npx-based MCP servers

[LIN-Xing-RU]

Problem Description

I'm encountering a "The system cannot find the file specified" error when mcp-cli tries to call MCP servers that use npx command. However, the exact same configuration works perfectly in Claude Desktop.

Current Configuration

Here's my server_config.json:

{
  "mcpServers": {
    "filesystem": {
      "command": "npx",
      "args": ["-y", "@modelcontextprotocol/server-filesystem", "/path/to/allowed/files"],
      "env": {}
    },
    "puppeteer": {
      "command": "npx",
      "args": [
        "-y",
        "@modelcontextprotocol/server-puppeteer"
      ]
    }
  }
}

Error Details

• Error Message: "The system cannot find the file specified"
• When it occurs: When mcp-cli tries to start/connect to MCP servers using npx
• Affected servers: All servers using npx command (filesystem, puppeteer, etc.)

Environment Information

• Operating System: Windows 10
• Node.js Version: 22.12.0
• NPM Version: 11.3.0
• NPX Version: 11.3.0