PYTHONIOENCODING needs to be set for fetch server on Windows

[jacocal]

OS: Windows 10
Using: Claude Desktop App
MCP: Fetch
Issue: Timeout

Happens every time I use the MCP

config file:

{
    "mcpServers": {
        "fetch-uvx": {
            "command": "uvx",
            "args": [
                "mcp-server-fetch",
                "--ignore-robots-txt"
            ]
        }
    }
}

Inspector logs:

[server] 'PORT' is not recognized as an internal or external command,
[server] operable program or batch file.
[server] PORT= node C:\Users\Jaco\AppData\Local\npm-cache\_npx\5a9d879542beca3a\node_modules\@modelcontextprotocol\inspector\server\build\index.js --env uvx --args="mcp-server-fetch" exited with code 1
[server] PORT= node C:\Users\Jaco\AppData\Local\npm-cache\_npx\5a9d879542beca3a\node_modules\@modelcontextprotocol\inspector\server\build\index.js --env uvx --args="mcp-server-fetch" restarted
[client] 'PORT' is not recognized as an internal or external command,
[client] operable program or batch file.
[client] PORT= node C:\Users\Jaco\AppData\Local\npm-cache\_npx\5a9d879542beca3a\node_modules\@modelcontextprotocol\inspector\client\bin\cli.js exited with code 1
[server] 'PORT' is not recognized as an internal or external command,
[server] operable program or batch file.
[client] PORT= node C:\Users\Jaco\AppData\Local\npm-cache\_npx\5a9d879542beca3a\node_modules\@modelcontextprotocol\inspector\client\bin\cli.js restarted
[server] PORT= node C:\Users\Jaco\AppData\Local\npm-cache\_npx\5a9d879542beca3a\node_modules\@modelcontextprotocol\inspector\server\build\index.js --env uvx --args="mcp-server-fetch" exited with code 1
[server] PORT= node C:\Users\Jaco\AppData\Local\npm-cache\_npx\5a9d879542beca3a\node_modules\@modelcontextprotocol\inspector\server\build\index.js --env uvx --args="mcp-server-fetch" restarted
[client] 'PORT' is not recognized as an internal or external command,
[client] operable program or batch file.
[client] PORT= node C:\Users\Jaco\AppData\Local\npm-cache\_npx\5a9d879542beca3a\node_modules\@modelcontextprotocol\inspector\client\bin\cli.js exited with code 1
[server] 'PORT' is not recognized as an internal or external command,
[server] operable program or batch file.
[client] PORT= node C:\Users\Jaco\AppData\Local\npm-cache\_npx\5a9d879542beca3a\node_modules\@modelcontextprotocol\inspector\client\bin\cli.js restarted
[server] PORT= node C:\Users\Jaco\AppData\Local\npm-cache\_npx\5a9d879542beca3a\node_modules\@modelcontextprotocol\inspector\server\build\index.js --env uvx --args="mcp-server-fetch" exited with code 1
[client] 'PORT' is not recognized as an internal or external command,
[client] operable program or batch file.
[server] PORT= node C:\Users\Jaco\AppData\Local\npm-cache\_npx\5a9d879542beca3a\node_modules\@modelcontextprotocol\inspector\server\build\index.js --env uvx --args="mcp-server-fetch" restarted
[client] PORT= node C:\Users\Jaco\AppData\Local\npm-cache\_npx\5a9d879542beca3a\node_modules\@modelcontextprotocol\inspector\client\bin\cli.js exited with code 1
[client] PORT= node C:\Users\Jaco\AppData\Local\npm-cache\_npx\5a9d879542beca3a\node_modules\@modelcontextprotocol\inspector\client\bin\cli.js restarted
[server] 'PORT' is not recognized as an internal or external command,
[server] operable program or batch file.
[server] PORT= node C:\Users\Jaco\AppData\Local\npm-cache\_npx\5a9d879542beca3a\node_modules\@modelcontextprotocol\inspector\server\build\index.js --env uvx --args="mcp-server-fetch" exited with code 1
--> Sending SIGTERM to other processes..
[client] 'PORT' is not recognized as an internal or external command,
[client] operable program or batch file.
[client] PORT= node C:\Users\Jaco\AppData\Local\npm-cache\_npx\5a9d879542beca3a\node_modules\@modelcontextprotocol\inspector\client\bin\cli.js exited with code 1
An error occurred: [
  {
    command: Command {
      killProcess: [Function (anonymous)],
      spawn: [Function: spawn],
      spawnOpts: [Object],
      index: 0,
      name: 'server',
      command: 'PORT= node C:\\Users\\Jaco\\AppData\\Local\\npm-cache\\_npx\\5a9d879542beca3a\\node_modules\\@modelcontextprotocol\\inspector\\server\\build\\index.js --env uvx --args="mcp-server-fetch"',
      prefixColor: '',
      env: {},
      cwd: '',
      ipc: undefined,
      close: [Subject],
      error: [Subject],
      stdout: [Subject],
      stderr: [Subject],
      timer: [Subject],
      messages: [Object],
      process: undefined,
      subscriptions: [],
      stdin: [Socket],
      pid: 24504,
      killed: false,
      exited: false,
      state: 'exited'
    },
    index: 0,
    exitCode: 1,
    killed: false,
    timings: {
      startDate: 2024-11-26T18:27:37.383Z,
      endDate: 2024-11-26T18:27:37.393Z,
      durationSeconds: 0.0092797
    }
  },
  {
    command: Command {
      killProcess: [Function (anonymous)],
      spawn: [Function: spawn],
      spawnOpts: [Object],
      index: 1,
      name: 'client',
      command: 'PORT= node C:\\Users\\Jaco\\AppData\\Local\\npm-cache\\_npx\\5a9d879542beca3a\\node_modules\\@modelcontextprotocol\\inspector\\client\\bin\\cli.js',
      prefixColor: '',
      env: {},
      cwd: '',
      ipc: undefined,
      close: [Subject],
      error: [Subject],
      stdout: [Subject],
      stderr: [Subject],
      timer: [Subject],
      messages: [Object],
      process: undefined,
      subscriptions: [],
      stdin: [Socket],
      pid: 7024,
      killed: true,
      exited: false,
      state: 'exited'
    },
    index: 1,
    exitCode: 1,
    killed: true,
    timings: {
      startDate: 2024-11-26T18:27:37.391Z,
      endDate: 2024-11-26T18:27:37.404Z,
      durationSeconds: 0.0133724
    }
  }
]

[mikeplavsky]

Potentially related #37 It fixed fetch for me.

{
  "mcpServers": {
    "fetch": {
      "command": "/path/to/uvx",
      "args": ["--python", "/path/to/python", "mcp-server-fetch"]
    }
  }
}

[jacocal]

Potentially related #37 It fixed fetch for me.

{
  "mcpServers": {
    "fetch": {
      "command": "/path/to/uvx",
      "args": ["--python", "/path/to/python", "mcp-server-fetch"]
    }
  }
}

Thanks for the reply, Issue persists on my side. Claude recognizes the MCP but I get the timeout error

[lvusyy]

Potentially related #37 It fixed fetch for me.

{
  "mcpServers": {
    "fetch": {
      "command": "/path/to/uvx",
      "args": ["--python", "/path/to/python", "mcp-server-fetch"]
    }
  }
}

Thanks for the reply, Issue persists on my side. Claude recognizes the MCP but I get the timeout error

    "fetch": {
      "command": "uvx",
      "args": ["mcp-server-fetch"],
      "env": {
        "PYTHONIOENCODING": "utf-8" 
      }
    }

[jaydealo7]

same problem,what about now?

[robbiebowman]

Potentially related #37 It fixed fetch for me.

{
  "mcpServers": {
    "fetch": {
      "command": "/path/to/uvx",
      "args": ["--python", "/path/to/python", "mcp-server-fetch"]
    }
  }
}

Thanks for the reply, Issue persists on my side. Claude recognizes the MCP but I get the timeout error

    "fetch": {
      "command": "uvx",
      "args": ["mcp-server-fetch"],
      "env": {
        "PYTHONIOENCODING": "utf-8" 
      }
    }

This fixed it for me. Thanks for sharing.