Socrad/rationalCalcServer

Rational Calculator MCP Server

This project integrates a C++ rational number calculator with a Go-based Model Context Protocol (MCP) server. The Go server exposes the C++ calculator as an MCP tool, allowing other MCP-compatible clients, such as gemini_cli, to perform rational number arithmetic.

Project Structure

• RationalSystem/: A Git submodule containing the C++ rational number calculator library.
• server/: Contains the Go MCP server implementation.
• Makefile: Provides commands for building both the C++ calculator and the Go server.

Features

• Rational Number Arithmetic: Utilizes a C++ library for precise calculations with rational numbers.
• Model Context Protocol (MCP) Integration: Exposes the calculator functionality as an MCP tool, enabling seamless integration with MCP-compatible systems like gemini_cli.
• Standard I/O Communication: The MCP server communicates via standard input/output (stdio)
• Simple Build Process: A Makefile simplifies the compilation and setup.

Getting Started

Prerequisites

• Go (version 1.24.5 or higher)
• C++ Compiler (g++ recommended)
• Git

Setup

1. Clone the repository:

   git clone --recurse-submodules https://github.com/Socrad/rationalCalcServer.git
   cd rationalCalcServer
   

   If you cloned without --recurse-submodules, initialize and update the submodule:

   git submodule update --init --recursive
   

2. Build the project: The Makefile will compile both the C++ rational calculator and the Go MCP server.

   make all
   

   This will create server/rational_calculator (the C++ executable) and server/mcp_server (the Go executable).

Integration with gemini_cli

This MCP server is designed to be integrated with gemini_cli as a custom tool. After building the mcp_server executable, you can configure gemini_cli's settings.json (or similar configuration file) to register this server as a tool provider.

Note: The exact configuration might vary based on your gemini_cli version and setup. Refer to gemini_cli documentation for precise tool registration details.

Once configured, the gemini_cli (and the underlying LLM) will be able to automatically invoke the rational_calculator tool for rational number operations.

Usage (MCP Tool)

Once the server is running and registered with an MCP client (like gemini_cli), you can interact with the rational_calculator tool. The tool expects three arguments: operand1 (string), operator (string), and operand2 (string).

Tool Name: rational_calculator Description: Performs calculations with integers and rational numbers. Use this tool for everyday arithmetic and comparisons.

The tool will return the result of the operation as a string.

Cleaning Up

To remove the compiled binaries:

make clean

Dependencies

The rationalCalcServer project relies on the following external repositories and tools:

• RationalSystem: Provides the Rational class and calculator_main.cpp for rational number arithmetic and comparison operations. Licensed under the MIT License.
• MCP Go SDK: Implements the Model Context Protocol (MCP) server to expose calculator_main.cpp operations as tools for LLM clients. Licensed under the MIT License.
• Go: Requires Go 1.18 or higher for building the MCP server.
• C++17 Compiler: Requires a C++17-compatible compiler (e.g., GCC, Clang) to build the rational_calculator executable.
• CMake (optional): Used to build the RationalSystem components if included in the build process.

Acknowledgements

This project builds upon the following open-source contributions:

• RationalSystem: For the robust Rational class implementation, developed with assistance from Google's Gemini.
• Model Context Protocol (MCP): For the standardized protocol enabling LLM integration, maintained by Anthropic and the Go team.

License

Distributed under the MIT License. See for more information.