DemoTool MCP Server

A modular Model Context Protocol (MCP) server for the DemoTool project. This server provides custom tools that AI assistants in Cursor can use to better understand and interact with the codebase.

What is MCP?

Model Context Protocol (MCP) is an open protocol that allows AI assistants to securely interact with external data sources and tools. This server exposes project-specific tools that Cursor can use to enhance development workflows.

Related MCP server: Basic MCP Server

Project Structure

The server is organized into a modular architecture for easy maintenance and scalability:

mcp-server/
├── src/
│   ├── config/           # Server configuration
│   │   ├── server.config.ts
│   │   └── index.ts
│   ├── server/           # Server setup and request handlers
│   │   ├── setup.ts
│   │   └── index.ts
│   ├── tools/            # Tool implementations
│   │   ├── tool-registry.ts    # Tool registry pattern
│   │   ├── hello-world.tool.ts # Example tool
│   │   └── index.ts
│   ├── types/            # TypeScript type definitions
│   │   ├── tool.types.ts
│   │   ├── server.types.ts
│   │   └── index.ts
│   └── index.ts          # Main entry point
├── dist/                 # Compiled JavaScript output
├── package.json
└── tsconfig.json

Available Tools

This MCP server currently provides:

1. hello_world - Returns a friendly hello world message

   • Optional parameter: name (string) - Name to greet, defaults to "World"

Installation

1. Install dependencies:

cd mcp-server
npm install

2. Build the server:

npm run build

Configuration in Cursor

To integrate this MCP server with Cursor:

Method 1: Using Cursor Settings UI

1. Open Cursor Settings

2. Navigate to Features → MCP

3. Click + Add New MCP Server

4. Configure:

   • Name: kids-daily-tool

   • Type: stdio

   • Command: node /home/fernando/code/kids-daily-tool/mcp-server/dist/index.js

Method 2: Manual Configuration (Advanced)

Edit Cursor's MCP configuration file directly:

Linux/Mac: ~/.config/cursor/mcp.json Windows: %APPDATA%\Cursor\mcp.json

Add this configuration:

{
  "mcpServers": {
    "kids-daily-tool": {
      "command": "node",
      "args": ["/home/fernando/code/kids-daily-tool/mcp-server/dist/index.js"],
      "env": {}
    }
  }
}

Usage in Cursor

Once configured, you can use natural language prompts in Cursor Composer to invoke the tool:

• "Say hello to me!"

• "Use the hello_world tool"

• "Call the hello_world MCP tool with name: Fernando"

Cursor will automatically detect when to use the MCP tool and execute it on your behalf. The tool will return a friendly greeting message.

Development

To modify the server:

1. Edit files in src/

2. Rebuild: npm run build

3. Restart Cursor to pick up changes

Troubleshooting

Server not showing up in Cursor

• Make sure you've built the server (npm run build)

• Verify the path in your configuration is absolute

• Restart Cursor after making configuration changes

Tool errors

• Check the Cursor Developer Console for error messages

• Verify file permissions on the project directory

• Ensure Node.js is available in your PATH

Extending the Server

The modular architecture makes it easy to add new tools. Follow these steps:

1. Create a New Tool

Create a new file in src/tools/, e.g., my-new-tool.tool.ts:

import {
  Tool,
  ToolDefinition,
  ToolArguments,
  ToolResult,
} from "../types/index.js";

export class MyNewTool implements Tool {
  getDefinition(): ToolDefinition {
    return {
      name: "my_new_tool",
      description: "Description of what your tool does",
      inputSchema: {
        type: "object",
        properties: {
          param1: {
            type: "string",
            description: "Description of param1",
          },
        },
        required: ["param1"],
      },
    };
  }

  async execute(args: ToolArguments): Promise<ToolResult> {
    // Implement your tool logic here
    const result = `Processing: ${args.param1}`;

    return {
      content: [
        {
          type: "text",
          text: result,
        },
      ],
    };
  }
}

2. Register the Tool

Add your tool to src/tools/index.ts:

export * from "./my-new-tool.tool.js";
import { MyNewTool } from "./my-new-tool.tool.js";

export function getAllTools(): Tool[] {
  return [
    new HelloWorldTool(),
    new MyNewTool(), // Add your tool here
  ];
}

3. Rebuild and Test

npm run build

That's it! The tool registry will automatically pick up your new tool.

Architecture Benefits

• Modularity: Each tool is self-contained in its own file

• Type Safety: Full TypeScript support with proper interfaces

• Scalability: Easy to add new tools without modifying core logic

• Maintainability: Clear separation of concerns

• Testability: Individual tools can be tested in isolation

Security Notes

• This server only provides read-only access to project information

• It runs locally and doesn't send data to external services

• Always review MCP server code before integrating it with your editor