ExpressJS MCP

# MCP Client Setup Guide This guide shows how to configure various MCP clients to work with Express-MCP. ## Quick Start Express-MCP now includes a native MCP server using the official `@modelcontextprotocol/sdk`: ```bash # Install npm install expressjs-mcp # Run native MCP server npx expressjs-mcp --url http://localhost:3000/mcp ``` ## Client Configurations ### Claude Desktop Create or update `~/Library/Application Support/Claude/claude_desktop_config.json`: ```json { "mcpServers": { "express-app": { "command": "npx", "args": ["expressjs-mcp", "--url", "http://localhost:3000/mcp"] } } } ``` ### Cursor IDE Add to `.cursor/mcp.json`: ```json { "mcpServers": { "express-app": { "command": "npx", "args": ["expressjs-mcp", "--url", "http://localhost:3000/mcp"] } } } ``` ### VS Code with MCP Extension Add to VS Code settings: ```json { "mcp.servers": [ { "name": "express-app", "command": "npx", "args": ["expressjs-mcp", "--url", "http://localhost:3000/mcp"] } ] } ``` ## Environment Variables You can also use environment variables: ```bash # Set the Express MCP URL export EXPRESS_MCP_URL=http://localhost:3000/mcp # Run the server npx expressjs-mcp ``` ## Advanced Configuration ### With Debug Logging ```json { "mcpServers": { "express-app": { "command": "npx", "args": ["expressjs-mcp", "--url", "http://localhost:3000/mcp", "--debug"] } } } ``` ### With Custom Environment ```json { "mcpServers": { "express-app": { "command": "npx", "args": ["expressjs-mcp", "--url", "http://localhost:3000/mcp"], "env": { "DEBUG": "true", "NODE_ENV": "development" } } } } ``` ## Testing the Connection ### 1. Start Your Express Server ```bash # Start your Express app with MCP node your-app.js ``` ### 2. Test MCP Server ```bash # Test the native MCP server npx expressjs-mcp --url http://localhost:3000/mcp --debug ``` ### 3. Verify Tools ```bash # Check available tools curl http://localhost:3000/mcp/tools ``` ## Troubleshooting ### Server Not Starting ```bash # Check if Express server is running curl http://localhost:3000/mcp/tools # Enable debug mode npx expressjs-mcp --debug # Check logs EXPRESS_MCP_URL=http://localhost:3000/mcp DEBUG=true npx expressjs-mcp ``` ### Tools Not Found ```bash # Verify tools are registered curl http://localhost:3000/mcp/tools | jq '.tools[].name' # Check MCP server connection npx expressjs-mcp --url http://localhost:3000/mcp --debug ``` ### Permission Issues ```bash # Make binary executable chmod +x node_modules/.bin/expressjs-mcp # Or use npx npx expressjs-mcp ``` ## Migration from Bridge Scripts If you were using the old bridge scripts: ### Old Configuration ```json { "mcpServers": { "express-app": { "command": "node", "args": ["/path/to/scripts/mcp-bridge.cjs"], "env": { "EXPRESS_MCP_URL": "http://localhost:3000/mcp" } } } } ``` ### New Configuration ```json { "mcpServers": { "express-app": { "command": "npx", "args": ["expressjs-mcp", "--url", "http://localhost:3000/mcp"] } } } ``` ## Benefits of Native Implementation 1. **Official SDK**: Uses Anthropic's official MCP SDK 2. **Better Performance**: Direct stdio communication 3. **Type Safety**: Full TypeScript support 4. **Error Handling**: Proper MCP error codes 5. **Maintainability**: Less custom code to maintain 6. **Compatibility**: Guaranteed protocol compliance 7. **Future Proof**: Updates with SDK improvements ## Next Steps - See [MCP_NATIVE_SETUP.md](./MCP_NATIVE_SETUP.md) for detailed setup - See [examples](../examples/) for usage examples - Report issues on GitHub