Windows: ERR_UNSUPPORTED_ESM_URL_SCHEME when running mcp-ssh

[sixiaopangai]

Description

When running mcp-ssh on Windows, the server fails to start with an ESM module loading error.

Error Message

node:internal/modules/esm/load:187
    throw new ERR_UNSUPPORTED_ESM_URL_SCHEME(parsed, schemes);
          ^

Error [ERR_UNSUPPORTED_ESM_URL_SCHEME]: Only URLs with a scheme in: file, data, and node are supported by the default ESM loader. On Windows, absolute paths must be valid file:// URLs. Received protocol 'c:'
    at throwIfUnsupportedURLScheme (node:internal/modules/esm/load:187:11)
    at defaultLoad (node:internal/modules/esm/load:82:3)
    at ModuleLoader.load (node:internal/modules/esm/loader:815:12)
    at ModuleLoader.loadAndTranslate (node:internal/modules/esm/loader:594:31)

Environment

• OS: Windows 11 (10.0.22631)
• Node.js: v22.x
• Package version: 1.1.0

Root Cause

In bin/mcp-ssh.js, the dynamic import() is called with a Windows absolute path directly:

const mainModule = path.join(__dirname, '..', 'server-simple.mjs');
import(mainModule);

On Windows, this results in a path like C:\Users\...\server-simple.mjs, but Node.js ESM loader requires file:// URLs for absolute paths on Windows.

Suggested Fix

Convert the path to a file:// URL before importing:

import path from 'path';
import { fileURLToPath, pathToFileURL } from 'url';

const __filename = fileURLToPath(import.meta.url);
const __dirname = path.dirname(__filename);

const mainModule = path.join(__dirname, '..', 'server-simple.mjs');
import(pathToFileURL(mainModule).href);

This change makes the code work correctly on both Windows and Unix-like systems.

Workaround

Users can manually edit the installed bin/mcp-ssh.js file to apply the fix above until an official release is available.