Rust Counter MCP

This project implements a simple Model Context Protocol (MCP) server in Rust that exposes a set of counter tools via the MCP protocol. The server allows clients to increment, decrement, and retrieve the value of a shared counter using defined tools.

Features

• Increment Tool: Increases the counter by 1.
• Decrement Tool: Decreases the counter by 1.
• Get Counter Tool: Returns the current value of the counter.
• MCP Protocol: Implements the MCP server protocol for tool-based interaction.

Code Overview

• The main logic is in src/main.rs.
• The HelloWorld struct manages the counter state using an async mutex for safe concurrent access.
• Tools are defined using the #[tool] macro and exposed via the MCP protocol.
• The server is started using Tokio and listens for requests over stdio.

Usage

Build

Make sure you have Rust and Cargo installed. Then run:

cargo build --release

Run

Start the MCP server:

cargo run --release

The server will listen for MCP requests over stdio.

Example Tool Calls

• Increment Counter:
  • Tool name: increment
  • Description: Increments the counter by 1 and returns the new value.
• Decrement Counter:
  • Tool name: decrement
  • Description: Decrements the counter by 1 and returns the new value.
• Get Counter Value:
  • Tool name: get_counter
  • Description: Returns the current value of the counter.

Dependencies

• tokio for async runtime
• rmcp for MCP protocol implementation

Project Structure

• src/main.rs: Main server implementation
• Cargo.toml: Rust dependencies and metadata

Notes

• The server is designed for demonstration and testing of MCP tool capabilities.
• You can extend the toolset by adding more methods to the HelloWorld struct and annotating them with the #[tool] macro.

License

MIT