MCP ChatGPT Multi-Server Suite

# 💱 MCP Currency Converter App A minimal TypeScript ChatGPT App using the Model Context Protocol (MCP) SDK with Express to provide real-time currency conversion for 160+ currencies. ## ✨ Features - 💱 **Real-time Currency Conversion**: Convert between 160+ currencies - 🔄 **Live Exchange Rates**: Up-to-date rates from exchangerate-api.com - 🎨 **Beautiful UI**: Dark mode with DaisyUI, Tailwind CSS, and Anime.js - 📱 **Responsive Design**: Works on desktop, tablet, and mobile - 🚀 **MCP Integration**: Uses @modelcontextprotocol/sdk - 🆓 **Free to Use**: No API key required (free tier: 1500 requests/month) - ⚡ **Auto-convert**: Real-time conversion as you type - 📊 **Live Rates Table**: View exchange rates for major currencies ## 🎯 Quick Start ### 1. Start the Server ```bash chmod +x start-currency.sh ./start-currency.sh ``` ### 2. Open in Browser ``` http://localhost:3001 ``` That's it! No API key required for basic usage. ## 🔧 Optional: Use API Key for Unlimited Access To remove the 1500 requests/month limit: 1. Get a free API key at: https://www.exchangerate-api.com/ 2. Set the environment variable: ```bash export EXCHANGE_RATE_API_KEY=your_key_here ``` 3. Restart the server ## 📊 MCP Tools Available ### 1. `convertCurrency` Converts an amount from one currency to another. **Parameters:** - `from` (string): Source currency code (e.g., "USD") - `to` (string): Target currency code (e.g., "EUR") - `amount` (number): Amount to convert **Example:** ```javascript await window.openai.callTool('convertCurrency', { from: 'USD', to: 'EUR', amount: 100 }); // Returns: { from: 'USD', to: 'EUR', amount: 100, result: 92.50, rate: 0.925, timestamp: '...' } ``` ### 2. `getSupportedCurrencies` Gets a list of all supported currency codes. **Example:** ```javascript await window.openai.callTool('getSupportedCurrencies', {}); // Returns: { currencies: { USD: 'US Dollar', EUR: 'Euro', ... }, count: 161 } ``` ### 3. `getExchangeRates` Gets all exchange rates for a base currency. **Parameters:** - `base` (string): Base currency code (e.g., "USD") **Example:** ```javascript await window.openai.callTool('getExchangeRates', { base: 'USD' }); // Returns: { base: 'USD', rates: { EUR: 0.925, GBP: 0.79, ... }, timestamp: '...' } ``` ## 🎨 Features Breakdown ### Auto-load Functionality - Page automatically calls `window.openai.callTool('convertCurrency', ...)` on load - Real-time conversion as you type or change currencies - Instant results with smooth animations ### Converter Interface - Select from/to currencies from dropdown - Enter amount to convert - See instant results - Swap currencies with one click - Popular conversion shortcuts ### Live Exchange Rates Table - Shows rates for major currencies - Updates every 60 seconds - Based on selected "from" currency ### Responsive Design - Mobile-friendly interface - Touch-optimized controls - Adapts to any screen size ## 🏗️ Architecture ``` Browser └─► window.openai.callTool('convertCurrency', { from, to, amount }) └─► POST http://localhost:3001/mcp/tools/call └─► MCP Server (currency-server.ts) └─► GET https://open.er-api.com/v6/latest/{currency} └─► Exchange Rate API └─► Returns real-time rates ``` ## 📁 Files - **src/currency-server.ts**: MCP server with currency conversion tools - **public-currency/index.html**: ChatGPT app frontend - **start-currency.sh**: Startup script - **dist/currency-server.js**: Compiled JavaScript ## 🌐 API Endpoints | Method | Path | Description | |--------|------|-------------| | GET | / | Serve currency converter UI | | GET | /mcp/tools/list | List available MCP tools | | POST | /mcp/tools/call | Execute MCP tool | ## 📝 Example Request ```bash curl -X POST http://localhost:3001/mcp/tools/call \ -H "Content-Type: application/json" \ -d '{ "name": "convertCurrency", "arguments": { "from": "USD", "to": "EUR", "amount": 100 } }' ``` **Response:** ```json { "from": "USD", "to": "EUR", "amount": 100, "result": 92.50, "rate": 0.925, "timestamp": "2024-01-01T12:00:00.000Z" } ``` ## 💡 Popular Currency Pairs The app includes quick-access buttons for: - USD → EUR - EUR → USD - GBP → USD - USD → JPY - USD → CNY - EUR → GBP - AUD → USD - USD → INR ## 🎯 Supported Currencies 160+ currencies including: - **USD** - US Dollar - **EUR** - Euro - **GBP** - British Pound - **JPY** - Japanese Yen - **AUD** - Australian Dollar - **CAD** - Canadian Dollar - **CHF** - Swiss Franc - **CNY** - Chinese Yuan - **INR** - Indian Rupee - And 150+ more! ## 🔧 Development ### Build TypeScript ```bash npm run build ``` ### Run in Development Mode ```bash npm run dev-currency ``` ### Expose with ngrok ```bash ngrok http 3001 ``` ## 🐛 Troubleshooting ### Port 3001 in use ```bash PORT=3002 node dist/currency-server.js ``` ### API rate limit exceeded - Get a free API key at https://www.exchangerate-api.com/ - Set `EXCHANGE_RATE_API_KEY` environment variable ### Currency not found - Check that you're using 3-letter ISO currency codes (e.g., USD, EUR) - Use `getSupportedCurrencies` to see all available currencies ## 📚 Technologies Used ### Backend - TypeScript - Express.js - @modelcontextprotocol/sdk - Axios - exchangerate-api.com ### Frontend - HTML5 - Tailwind CSS - DaisyUI - Anime.js - Vanilla JavaScript ## 🌟 Future Enhancements - [ ] Historical exchange rate charts - [ ] Favorite currency pairs - [ ] Offline mode with cached rates - [ ] Currency converter calculator - [ ] Multi-currency conversion (convert to multiple currencies at once) - [ ] Rate alerts ## 📄 License MIT --- **Built with ❤️ using TypeScript, Express, and the Model Context Protocol**