MCP Integration Challenge: Proxy & RAG Foundations
AI Protocol Engineer Challenge: Week 1
This repository contains the complete implementation for the MCP Integration, Proxy & RAG Foundations challenge using TypeScript/NodeJS with LangGraph.js.
Project Overview
This project implements a comprehensive MCP (Model Context Protocol) ecosystem including:
- MCP Proxy Server: Routes requests to multiple downstream MCP servers
- Dev Assistant Agent: LangGraph.js-based agent with RAG capabilities
- Mock Knowledge Base: Sample data for testing RAG functionality
- MCP Client Tester: Testing tools for MCP server interactions
- IDE Integration: Configuration for VS Code/Cursor MCP support
Architecture
┌─────────────────┐ ┌──────────────────┐ ┌─────────────────┐
│ IDE Client │ ──▶│ MCP Proxy │ ──▶│ Downstream MCP │
│ (VS Code/Cursor)│ │ Server │ │ Servers │
└─────────────────┘ └──────────────────┘ └─────────────────┘
│ │
▼ │
┌──────────────────┐ │
│ Dev Assistant │ │
│ Agent │ │
│ (LangGraph.js) │ │
└──────────────────┘ │
│ │
▼ │
┌──────────────────┐ │
│ RAG Pipeline │ │
│ (LangChain JS) │ │
└──────────────────┘ │
│ │
▼ │
┌──────────────────┐ │
│ Mock Knowledge │◀────────────┘
│ Base │
└──────────────────┘
Project Structure
mcp/
├── src/
│ ├── proxy/ # MCP Proxy Server implementation
│ ├── agent/ # Dev Assistant Agent with LangGraph.js
│ ├── rag/ # RAG setup and utilities
│ ├── client/ # MCP Client testing tools
│ ├── types/ # TypeScript type definitions
│ └── utils/ # Shared utilities
├── tests/ # Unit and integration tests
├── docs/ # Documentation
│ ├── protocols_understanding.md
│ ├── mcp_server_exploration.md
│ ├── advanced_mcp_concepts.md
│ ├── realtime_rag_notes.md
│ └── ide_mcp_integration.md
├── mock_knowledge_base/ # Sample data for RAG
│ ├── docs/
│ ├── code/
│ ├── tickets/
│ └── jira_tickets.json
├── package.json
├── tsconfig.json
└── README.md
Technology Stack
Core Technologies
- Runtime: Node.js 18+
- Language: TypeScript 5.5+
- Agent Framework: LangGraph.js
- RAG Framework: LangChain JS
Dependencies
- Protocol Communication: Built-in fetch, axios
- Agent Building: @langchain/langgraph
- RAG Components: @langchain/community, langchain
- Web Framework: Express.js
- Testing: Vitest
- Development: tsx, eslint, prettier
Quick Start
Prerequisites
- Node.js 18 or later
- npm or yarn package manager
- Git
Installation
- Clone the repository:
git clone https://github.com/your-username/mcp.git
cd mcp
- Install dependencies:
npm install --legacy-peer-deps
- Build the project:
- Run tests:
Running Components
1. MCP Proxy Server
npm run proxy:start
# Starts on http://localhost:8002
2. Dev Assistant Agent
3. MCP Client Tester
4. Development Mode (Watch)
Environment Setup
Required Environment Variables
Create a .env file in the root directory:
# OpenAI API Key (for LangChain)
OPENAI_API_KEY=your_openai_api_key
# GitHub Token (for GitHub MCP server)
GITHUB_TOKEN=your_github_token
# Google Drive Credentials (for GDrive MCP server)
GOOGLE_DRIVE_CLIENT_ID=your_client_id
GOOGLE_DRIVE_CLIENT_SECRET=your_client_secret
# Atlassian Credentials (for Atlassian MCP server)
ATLASSIAN_API_TOKEN=your_atlassian_token
ATLASSIAN_INSTANCE_URL=your_instance_url
# Proxy Configuration
PROXY_PORT=8002
PROXY_HOST=localhost
# Logging
LOG_LEVEL=info
MCP Server Configuration
The proxy server can route to multiple downstream MCP servers:
Supported Servers
- Filesystem: Local file system access
- GitHub: Repository and issue management
- Google Drive: Document access and management
- Atlassian: JIRA and Confluence integration
Proxy Routing Configuration
// src/proxy/config.ts
export const serverRoutes = {
'filesystem': 'http://localhost:8001',
'github': 'http://localhost:8003',
'gdrive': 'http://localhost:8004',
'atlassian': 'http://localhost:8005'
};
IDE Integration
VS Code Setup
- Install the Copilot Chat extension
- Add to your
settings.json:
{
"github.copilot.chat.mcp.include": [
"http://localhost:8002/mcp"
]
}
Cursor Setup
- Open Cursor settings
- Add MCP server URL:
http://localhost:8002/mcp
Testing
Run All Tests
Run Specific Test Suites
npm run test:proxy # Proxy server tests
npm run test:agent # Agent tests
npm run test:rag # RAG pipeline tests
npm run test:client # Client tests
Test Coverage
Documentation
Development Workflow
Code Style
- ESLint for linting
- Prettier for formatting
- TypeScript strict mode enabled
Git Workflow
# Format code
npm run format
# Lint code
npm run lint
# Run tests before commit
npm test
# Build before push
npm run build
Features Implemented
✅ Task 1: Environment Setup & Protocol Study
🔄 Upcoming Tasks
Troubleshooting
Common Issues
- Dependency conflicts: Use
npm install --legacy-peer-deps - TypeScript errors: Ensure TypeScript 5.5+ is installed
- Build failures: Check Node.js version (18+ required)
- Test failures: Verify environment variables are set
Getting Help
- Check the documentation for detailed guides
- Review the protocols understanding document
- Examine test files for usage examples
- Check GitHub issues for known problems
Contributing
- Fork the repository
- Create a feature branch:
git checkout -b feature/new-feature - Make changes and add tests
- Run
npm test and npm run lint - Commit changes:
git commit -m 'Add new feature' - Push to branch:
git push origin feature/new-feature - Submit a pull request
License
MIT License - see LICENSE file for details.
For questions or support, please open an issue on GitHub.