Coin Flip MCP

🚀 A Coin's MCP Server

An MCP server that provides real random coin flips using the random.org randomness API. This server demonstrates the Model Context Protocol by offering tools with configurable sides.

🚀 Quick Start

This MCP server uses the random.org API to offer real random coin flips and demonstrates the Model Context Protocol through tools with configurable sides.

✨ Features

Tools

• flip_coin - Flip a coin with configurable sides
  • Optional sides parameter (default: 2)
  • Uses true randomness from random.org
  • Special handling for edge cases (0, 1, or negative sides)
  • For 2 sides: Returns "heads" or "tails"
  • For 3 sides: Returns "heads", "tails", or "_"
  • For n > 3 sides: Returns "It landed on side X"

📦 Installation

To use with Claude Desktop, add the server configuration:

On MacOS: ~/Library/Application Support/Claude/claude_desktop_config.json On Windows: %APPDATA%/Claude/claude_desktop_config.json%

{
  "mcpServers": {
    "coin-flip": {
      "command": "npx",
      "args": ["-y", "@modelcontextprotocol/server-coin-flip"]
    }
  }
}

💻 Usage Examples

Basic Usage

Once connected to an MCP client like Claude Desktop, you can interact with the coin flip tool using natural language. For example:

• "Flip a coin"
• "Roll a six-sided die"
• "Give me a random number between 1 and 20"

The server will use the true randomness from random.org to generate results.

🔧 Technical Details

Development

Install dependencies:

npm install

Build the server:

npm run build

Development with automatic rebuild:

npm run watch

Debugging

Since MCP servers communicate via stdio, debugging can be challenging. We recommend using the MCP Monitor:

npx @modelcontextprotocol/inspector node build/index.js

🤝 Contribution

Contributions are welcome! Please feel free to submit pull requests.

📄 License

MIT