Kotlin Crypto Price Spring MCP Server Demo

A demonstration project showcasing the integration of Spring AI's Model Context Protocol (MCP) server with a cryptocurrency price API service. This project allows AI models to retrieve real-time cryptocurrency information through a standardized interface.

Overview

This project implements a Spring Boot application that serves as an MCP server, providing tools for AI models to:

1. Search for cryptocurrencies by name or symbol
2. Retrieve market data for specific cryptocurrencies

The application uses the CoinGecko API to fetch real-time cryptocurrency data.

Features

• Cryptocurrency Search: Search for cryptocurrencies, exchanges, categories, and NFTs
• Market Data Retrieval: Get detailed market data for specific cryptocurrencies
• MCP Integration: Exposes functionality as tools for AI models via Spring AI's MCP server
• Logging: Comprehensive logging of tool requests and responses

Technologies

• Kotlin 1.9.25
• Spring Boot 3.4.4
• Spring AI MCP Server
• Model Context Protocol SDK 0.8.1
• Java 21

Project Structure

src/main/kotlin/org/gaplo917/mcpservercoinprice/
├── CoinPriceService.kt         # Service for cryptocurrency data retrieval
├── McpServerCoinPriceApplication.kt  # Main application class

Getting Started

Prerequisites

• JDK 21 or higher
• Gradle

Running the Application

./gradlew bootRun

The MCP server will start on the default port (typically 8080).

API Tools

The application exposes the following tools for AI models:

1. Search Cryptocurrency

@Tool(description = "search cryptocurrency information by user input query.")
fun searchCryptocurrency(query: String): CryptoData

2. Get Market Data

@Tool(description = "get cryptocurrency market data by id. The id must be used by the return of the searchCryptocurrency tools.")
fun getMarketDataByCryptocurrencyId(id: String): CryptoMarketData

Data Models

• CryptoData: Contains lists of coins, exchanges, categories, and NFTs
• CryptoMarketData: Contains market data including tickers for a specific cryptocurrency
• Coin: Represents a cryptocurrency with its ID, name, symbol, and market cap rank
• Ticker: Contains trading information for a cryptocurrency on a specific market

Integration with AI Models

This server can be used with AI models that support the Model Context Protocol (MCP), allowing them to retrieve cryptocurrency data in a standardized way. The Spring AI MCP Server handles the communication between the AI model and the cryptocurrency service.

License

This project is licensed under the terms included in the LICENSE file.

References

• Spring AI Documentation
• Model Context Protocol
• CoinGecko API