Deno MCP

🚀 @cong/mcp-deno

A secure MCP (Model Context Protocol) server enabling AI assistants such as Claude to execute TypeScript and JavaScript code via Deno.

🚀 Quick Start

This project provides a secure MCP server for AI assistants to execute TypeScript and JavaScript code. You can install and use it according to the following steps.

✨ Features

• 🔒 Secure code execution: Leverage Deno's permission system for secure code execution.
• 🚀 TypeScript and JavaScript support: Support TypeScript and JavaScript with a full Deno runtime.
• 🛡️ Configurable permissions: Set permissions at server startup.
• 🔌 MCP compliant: Ensure seamless integration with AI assistants.
• ⚡ Fast and lightweight: Feature minimal dependencies for high - speed performance.

📦 Installation

Install from JSR:

deno add jsr:@cong/mcp-deno

Or run directly:

deno run --allow-all jsr:@cong/mcp-deno

💻 Usage Examples

Basic Usage

With Claude Desktop

Add to your Claude Desktop configuration:

{
  "mcpServers": {
    "deno-executor": {
      "command": "deno",
      "args": [
        "run",
        "--allow-all",
        "jsr:@cong/mcp-deno"
      ]
    }
  }
}

Advanced Usage

Permission Configuration

Control what the executed code can access by modifying the startup arguments:

{
  "mcpServers": {
    "deno-executor": {
      "command": "deno", 
      "args": [
        "run",
        "--allow-net=example.com",
        "--allow-read=/tmp",
        "--allow-write=/tmp",
        "jsr:@cong/mcp-deno"
      ]
    }
  }
}

Available permission flags:

• --allow-net[=<allow-list>]: Allow network access.
• --allow-read[=<allow-list>]: Allow file system read access.
• --allow-write[=<allow-list>]: Allow file system write access.
• --allow-run[=<allow-list>]: Allow running subprocesses.
• --allow-env[=<allow-list>]: Allow environment access.
• --allow-all: Allow all permissions (use with caution).

📚 Documentation

Development

# Install dependencies
deno cache main.ts

# Run in development mode
deno task dev

# Run tests
deno task test

# Type check
deno check main.ts

Debugging with MCP Inspector

For debugging and testing your MCP server, use the MCP Inspector:

# Install MCP Inspector
npm install -g @modelcontextprotocol/inspector

# Run the server with inspector
npx @modelcontextprotocol/inspector deno run --allow-all jsr:@cong/mcp-deno

# Or test locally
npx @modelcontextprotocol/inspector deno run --allow-all main.ts

🔧 Technical Details

This MCP server prioritizes security through:

• Subprocess isolation: Code runs in separate Deno processes.
• Explicit permissions: Only granted permissions are available to executed code.
• No persistent state: Each execution is independent.
• Permission error handling: Provide clear feedback when permissions are insufficient.

📄 License

MIT

Contributing

Contributions are welcome! Please open an issue or submit a pull request.