MCP Server Node

A comprehensive MCP (Model Context Protocol) server implementation in Node.js that exposes multiple resource types including file system information, system details, and generated content.

Features

This MCP server provides access to various types of resources without requiring any external APIs:

🗂️ File System Resources

• Current Directory Listing (file://current-directory) - Lists files and directories in the current working directory with metadata
• Package Information (file://package-info) - Displays package.json information if available

💻 System Information Resources

• System Info (system://info) - Comprehensive system information including OS, architecture, Node.js version, memory usage, CPU count, load average, and user info
• Environment Variables (system://env) - Non-sensitive environment variables (automatically filters out passwords, secrets, keys, and tokens)

📝 Generated Content Resources

• Lorem Ipsum Text (generated://lorem) - Dynamically generated Lorem Ipsum placeholder text with random paragraph and sentence counts
• Sample Data (generated://data) - Generated sample user data in JSON format with realistic fake data

⚙️ Configuration Resources

• MCP Server Config (config://mcp-server) - Current server configuration, capabilities, and metadata

Installation & Usage

Using npx (Recommended)

npx mcp-server-node

Global Installation

npm install -g mcp-server-node
mcp-server-node

Local Installation

npm install mcp-server-node
npx mcp-server-node

MCP Protocol Usage

The server communicates via JSON-RPC over stdin/stdout following the Model Context Protocol specification.

Initialize the Server

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "initialize",
  "params": {}
}

List Available Resources

{
  "jsonrpc": "2.0",
  "id": 2,
  "method": "resources/list",
  "params": {}
}

Read a Specific Resource

{
  "jsonrpc": "2.0",
  "id": 3,
  "method": "resources/read",
  "params": {
    "uri": "system://info"
  }
}

Example Responses

Resource List Response

{
  "jsonrpc": "2.0",
  "id": 2,
  "result": {
    "resources": [
      {
        "uri": "file://current-directory",
        "name": "Current Directory Listing",
        "description": "Lists files and directories in the current working directory",
        "mimeType": "application/json"
      },
      {
        "uri": "system://info",
        "name": "System Information",
        "description": "Basic system information including OS, architecture, and Node.js version",
        "mimeType": "application/json"
      }
    ]
  }
}

Resource Read Response

{
  "jsonrpc": "2.0",
  "id": 3,
  "result": {
    "contents": [
      {
        "uri": "system://info",
        "mimeType": "application/json",
        "text": "{\n  \"platform\": \"darwin\",\n  \"architecture\": \"arm64\",\n  \"nodeVersion\": \"v18.17.0\",\n  \"hostname\": \"example-host\",\n  \"uptime\": 12345,\n  \"totalMemory\": 17179869184,\n  \"freeMemory\": 8589934592,\n  \"cpuCount\": 8,\n  \"loadAverage\": [1.5, 1.8, 2.1],\n  \"timestamp\": \"2024-01-01T12:00:00.000Z\"\n}"
      }
    ]
  }
}

Integration with Claude Desktop

To use this MCP server with Claude Desktop, add it to your Claude Desktop configuration:

macOS

Edit ~/Library/Application Support/Claude/claude_desktop_config.json:

{
  "mcpServers": {
    "mcp-server-node": {
      "command": "npx",
      "args": ["mcp-server-node"]
    }
  }
}

Windows

Edit %APPDATA%\\Claude\\claude_desktop_config.json:

{
  "mcpServers": {
    "mcp-server-node": {
      "command": "npx",
      "args": ["mcp-server-node"]
    }
  }
}

Testing the Server

You can test the server locally using command line tools:

# Test initialization
echo '{"jsonrpc": "2.0", "id": 1, "method": "initialize", "params": {}}' | npx mcp-server-node

# Test resource listing
echo '{"jsonrpc": "2.0", "id": 2, "method": "resources/list", "params": {}}' | npx mcp-server-node

# Test reading system info
echo '{"jsonrpc": "2.0", "id": 3, "method": "resources/read", "params": {"uri": "system://info"}}' | npx mcp-server-node

# Test reading generated content
echo '{"jsonrpc": "2.0", "id": 4, "method": "resources/read", "params": {"uri": "generated://lorem"}}' | npx mcp-server-node

Security Features

• Environment Variable Filtering: Automatically filters out sensitive environment variables containing keywords like "password", "secret", "key", or "token"
• No External Dependencies: Uses only Node.js built-in modules
• Read-Only Operations: All resources are read-only and don't modify system state
• Sandboxed Execution: Only accesses local system information and current directory

Requirements

• Node.js: Version 12.0.0 or higher
• Platform: Cross-platform (Windows, macOS, Linux)

Logging

The server logs activities to mcp_server_node.log in the current working directory. This keeps stdout clean for MCP protocol communication while providing debugging information.

Contributing

This is a simple, self-contained MCP server implementation. Feel free to fork and modify for your specific use cases.

License

MIT License - see the package.json file for details.

Related

• Model Context Protocol Specification
• Claude Desktop
• MCP Servers Repository