Demo MCP Server

A comprehensive boilerplate Model Context Protocol (MCP) server built with TypeScript using Domain-Driven Design patterns and dynamic component loading.

🚀 Features

Domain-Driven Design: Clean architecture with separated concerns
Dynamic Component Loading: File-based automatic loading of MCP components
TypeScript: Full type safety and modern JavaScript features
Dependency Injection: Modular and testable architecture
Example Components: Ready-to-use tools, resources, and prompts
Comprehensive Logging: Detailed startup and operation logging
Graceful Shutdown: Proper cleanup and resource management

📁 Project Structure

src/
├── index.ts                 # Main entry point
├── types/                   # Type definitions
│   └── index.ts            # MCP interfaces and types
├── services/                # Business logic services
│   ├── index.ts            # Services barrel export
│   └── module-loader-service.ts  # Dynamic module loading
├── server/                  # MCP server wrapper
│   ├── index.ts            # Server barrel export
│   └── my-mcp-server.ts    # Main server implementation
├── tools/                   # MCP tools directory
│   ├── index.ts            # Auto-loading tools
│   ├── calculator-tools.ts # Example arithmetic tools
│   └── text-processing-tools.ts # Example text tools
├── resources/               # MCP resources directory
│   ├── index.ts            # Auto-loading resources
│   ├── system-info-resources.ts # System information
│   └── config-resources.ts # Configuration data
└── prompts/                 # MCP prompts directory
    ├── index.ts            # Auto-loading prompts
    ├── code-review-prompts.ts # Code analysis prompts
    └── writing-assistance-prompts.ts # Writing help prompts

🛠️ Installation

Clone the repository:

git clone <repository-url>
cd demo-mcp-dev-1

Install dependencies:
```
npm install
```
Build the project:
```
npm run build
```

🎯 Usage

Development Mode

Run the server in development mode with hot reloading:

npm run dev

Production Mode

Build and run the server in production:

npm run build
npm start

Direct Execution

Run the compiled server directly:

node dist/index.js

🔧 Available Tools

Calculator Tools

add - Add two numbers
subtract - Subtract two numbers
multiply - Multiply two numbers
divide - Divide two numbers (with zero-division protection)

Text Processing Tools

transform-text - Transform text (uppercase, lowercase, capitalize, reverse, word-count)
analyze-text - Analyze text and provide detailed statistics

📚 Available Resources

System Information

system://info - System and environment information
env://{varName} - Access environment variables
process://info - Node.js process information

Configuration

config://app - Application configuration
settings://{category}/{key} - Dynamic configuration settings
health://status - Health and status information

📝 Available Prompts

Code Review Prompts

review-code - Comprehensive code review with focus areas
refactor-code - Code refactoring suggestions
document-code - Generate code documentation

Writing Assistance

write-email - Professional email generation
write-technical-doc - Technical documentation creation
summarize-meeting - Meeting summary generation

🏗️ Architecture

Domain-Driven Design

The project follows DDD principles with clear separation of concerns:

Types: Domain interfaces and contracts
Services: Business logic and operations
Server: Infrastructure and MCP integration
Components: MCP-specific implementations (tools, resources, prompts)

Dynamic Component Loading

The ModuleLoaderService automatically discovers and loads MCP components:

Scans component directories for TypeScript/JavaScript files
Dynamically imports modules using file URLs
Validates module contracts
Registers components with the MCP server

Dependency Injection

The MyMCPServer class uses dependency injection patterns:

Abstract base classes for extensibility
Interface-based dependencies
Configurable service injection
Clean separation between SDK and business logic

🔌 Adding New Components

Adding a New Tool

Create a new file in src/tools/ (e.g., my-new-tool.ts)
Export an MCP module with the required structure:

import { z } from "zod";
import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
import type { MCPModule } from "../types/index.js";

async function register(server: McpServer): Promise<void> {
  server.registerTool(
    "my-tool",
    {
      title: "My Tool",
      description: "Description of what my tool does",
      inputSchema: {
        param1: z.string().describe("First parameter"),
        param2: z.number().describe("Second parameter")
      }
    },
    async ({ param1, param2 }) => ({
      content: [
        {
          type: "text",
          text: `Tool result: ${param1} - ${param2}`
        }
      ]
    })
  );
}

export const myNewTool: MCPModule = {
  register,
  metadata: {
    name: "my-new-tool",
    description: "My new tool implementation",
    version: "1.0.0",
    author: "Your Name"
  }
};

export default myNewTool;

The tool will be automatically loaded on server startup!

Adding a New Resource

Create a new file in src/resources/ (e.g., my-resource.ts)
Export an MCP module following the same pattern as tools
Use server.registerResource() in the register function

Adding a New Prompt

Create a new file in src/prompts/ (e.g., my-prompt.ts)
Export an MCP module following the same pattern
Use server.registerPrompt() in the register function

🧪 Testing

Run the test suite:

npm test

Run linting:

npm run lint

Type checking:

npm run type-check

🔍 Debugging

The server provides comprehensive logging during startup and operation:

Component discovery and loading
Registration success/failure
Server status and configuration
Error details and stack traces

📊 Configuration

The server is configured in src/index.ts:

const serverConfig: MCPServerConfig = {
  name: "demo-mcp-server",
  version: "1.0.0",
  capabilities: {
    tools: true,
    resources: true,
    prompts: true,
    logging: true
  }
};

🤝 Contributing

Fork the repository
Create a feature branch
Make your changes
Add tests if applicable
Submit a pull request

📄 License

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

🙏 Acknowledgments

Built with the Model Context Protocol TypeScript SDK
Inspired by Domain-Driven Design principles
Thanks to the MCP community for excellent documentation and examples