MCP Server: Weather and Time Information Service

Project Overview

This Model Context Protocol (MCP) server is a learning project that leverages the RMCP (Rust Model Context Protocol) library to demonstrate:

• Async Rust programming with tokio
• Implementing a flexible microservice architecture
• Using the RMCP SDK for building extensible tools

The server provides two primary tools:

1. Weather Information: Retrieve weather data for a specific city and country
2. Local Time: Get the current local time for a given city and country

About RMCP

RMCP is a modern Rust SDK for the Model Context Protocol, offering:

• Clean and efficient async runtime with tokio
• Flexible and extensible tool implementation
• Improved data type handling compared to official SDKs
• Support for various transport mechanisms
  • Server-Sent Events (SSE) for real-time communication
  • Lightweight and efficient one-way server-to-client data streaming
  • Built-in reconnection support and event tracking

Purpose

The primary goal of this project is to:

• Learn Rust programming
• Explore RMCP library capabilities

Features

• Weather data retrieval
• Local time information
• Stdio-based communication
• Structured logging with tracing

Prerequisites

• Rust (latest stable version)
• Cargo package manager
• just command runner
  • Install with Homebrew: brew install just
  • Install with Cargo: cargo install just
• API keys for:
  • WeatherAPI for weather data
  • IP Geolocation API for time data

Configuration

The server can be configured using the following environment variables:

• BIND_ADDRESS: The IP address to bind the server to (default: 0.0.0.0)
• PORT: The port number to listen on (default: 8000)

Example usage:

# Bind to localhost on port 3000
BIND_ADDRESS=127.0.0.1 PORT=3000 cargo run

# Use default bind address but change port
PORT=8080 cargo run

Environment Setup

1. Copy the example environment file:

   cp .env.example .env
   

2. Edit the .env file and replace the placeholder values with your actual API keys:

   • WEATHER_API_KEY: Get it from WeatherAPI
   • IP_GEOLOCATION_API_KEY: Get it from IP Geolocation API

3. Optionally, you can also configure:

   • BIND_ADDRESS: The IP address to bind the server to (default: 0.0.0.0)
   • PORT: The port number to listen on (default: 8000)

Installation

1. Clone the repository:

   git clone https://github.com/sergei-grigorev/mcp-server-play.git
   cd mcp-server-play
   

2. Build the project:

   cargo build
   

Development Commands

The project uses just as a command runner. Available commands:

just                # List available commands
just build          # Build release artifact
just check          # Run checks (clippy, fmt, etc.)
just clean          # Clean build artifacts
just format         # Format code using rustfmt
just serve          # Run the server in development mode
just test           # Run tests

Running the Server

Run the server using just:

just serve

Project Structure

• src/main.rs: Entry point and server initialization
• src/api/
  • mod.rs: Main server implementation
  • weather.rs: Weather data retrieval logic
  • weather/response.rs: Weather API response models
  • time.rs: Time data retrieval logic
  • time/response.rs: Time API response models
• src/models/
  • mod.rs: Models module definitions
  • weather.rs: Weather request/response models
  • time.rs: Time request/response models

Tools and Endpoints

Weather Information

• Endpoint: get_weather
• Parameters:
  • city: Name of the city
  • country: Country code
  • unit: Temperature unit (optional)
    • Values: C (Celsius) or F (Fahrenheit)
    • Default: C

Local Time

• Endpoint: get_local_time
• Parameters:
  • city: Name of the city
  • country: Country code

License

MIT