Code Explainer MCP

A Cloudflare Worker that serves as an MCP (Model Context Protocol) server for code explanation. It analyzes and explains code with a comprehensive breakdown of structure and functionality.

Features

• Architecture Diagram: Generates an ASCII diagram showing the overall structure, relationships between components, and data flow.
• Core Functionality Analysis: Identifies and explains the primary purpose of the code based on pattern recognition.
• Component Breakdown: Lists all main classes and functions with brief descriptions of their roles.
• Multi-language Support: Analyzes code in various programming languages including JavaScript, TypeScript, Python, Java, C#, and more.
• JSDoc/Docstring Recognition: Extracts and utilizes existing documentation in the code.
• Secure API: Bearer token authentication to secure your endpoints.

How It Works

The Code Explainer analyzes source code using a combination of techniques:

1. Pattern Recognition: Identifies code structures and common patterns
2. Relationship Analysis: Maps dependencies between components
3. Documentation Extraction: Prioritizes existing documentation comments
4. Architecture Visualization: Creates ASCII diagrams of the code structure
5. Component Description: Provides semantic descriptions of functions and classes

All processing happens within the Cloudflare Worker with no external dependencies.

Installation

Prerequisites

• Node.js (version 12 or higher)
• Wrangler (Cloudflare Workers CLI)
• A Cloudflare account

Setup

1. Clone this repository:

   git clone https://github.com/BillDuke13/code-explainer-mcp.git
   cd code-explainer-mcp

2. Install dependencies:

   npm install

3. Configure your secret key:

   • Edit wrangler.jsonc and replace YOUR_SECRET_KEY_HERE with your chosen secret key, or
   • Use Cloudflare secrets (recommended for production):

     wrangler secret put SHARED_SECRET

4. Deploy to Cloudflare Workers:

   npm run deploy

Usage

API Endpoint

Send a POST request to your worker URL with the following JSON body:

{
  "method": "explainCode",
  "params": ["your code here", "programming language"]
}

Include the Authorization header with your secret key:

Authorization: Bearer YOUR_SECRET_KEY_HERE

Response Format

The response will be a JSON object with a result field containing the code analysis:

{
  "result": "# Code Analysis for JavaScript Code

## Architecture Diagram
...

## Core Functionality
..."
}

Example Usage

JavaScript (Browser)

async function explainCode(code, language) {
  const response = await fetch('https://your-worker-url.workers.dev', {
    method: 'POST',
    headers: {
      'Content-Type': 'application/json',
      'Authorization': 'Bearer YOUR_SECRET_KEY_HERE',
    },
    body: JSON.stringify({
      method: "explainCode",
      params: [code, language]
    }),
  });
  
  if (!response.ok) {
    throw new Error(`HTTP error! status: ${response.status}`);
  }
  
  const data = await response.json();
  return data.result;
}

// Example usage
const jsCode = `function add(a, b) { return a + b; }`;
explainCode(jsCode, "javascript")
  .then(explanation => console.log(explanation))
  .catch(error => console.error('Error:', error));

Python (Requests)

import requests
import json

def explain_code(code, language, api_url, secret_key):
    headers = {
        'Content-Type': 'application/json',
        'Authorization': f'Bearer {secret_key}'
    }
    
    payload = {
        'method': 'explainCode',
        'params': [code, language]
    }
    
    response = requests.post(api_url, headers=headers, json=payload)
    response.raise_for_status()
    
    return response.json()['result']

# Example usage
code = "def hello(): print('Hello, world!')"
explanation = explain_code(code, "python", "https://your-worker-url.workers.dev", "YOUR_SECRET_KEY_HERE")
print(explanation)

Node.js (Axios)

const axios = require('axios');

async function explainCode(code, language) {
  try {
    const response = await axios.post('https://your-worker-url.workers.dev', {
      method: 'explainCode',
      params: [code, language]
    }, {
      headers: {
        'Content-Type': 'application/json',
        'Authorization': 'Bearer YOUR_SECRET_KEY_HERE'
      }
    });
    
    return response.data.result;
  } catch (error) {
    console.error('Error:', error.response ? error.response.data : error.message);
    throw error;
  }
}

// Example usage
const codeToAnalyze = `
class Person {
  constructor(name) {
    this.name = name;
  }
  
  sayHello() {
    return \`Hello, my name is \${this.name}\`;
  }
}
`;

explainCode(codeToAnalyze, 'javascript')
  .then(explanation => console.log(explanation))
  .catch(err => console.error('Failed to explain code:', err));

Local Development

1. Clone the repository and install dependencies:

   git clone https://github.com/BillDuke13/code-explainer-mcp.git
   cd code-explainer-mcp
   npm install

2. Run the development server:

   wrangler dev

3. Test the endpoint locally:

   curl -X POST http://localhost:8787 \
     -H "Content-Type: application/json" \
     -H "Authorization: Bearer YOUR_SECRET_KEY_HERE" \
     -d '{"method":"explainCode","params":["function hello() { return "Hello World"; }","javascript"]}'

Development Guidelines

• Follow TypeScript best practices
• Add comments for complex logic
• Update documentation for public API changes
• Add tests for new features

Security

• The API is secured with Bearer token authentication
• Use environment secrets for storing the shared secret in production
• Do not commit your actual secret key to version control
• Rate limiting is recommended for production deployments

License

This project is licensed under the Apache License 2.0 - see the LICENSE file for details.