MCP Calculator Service

A Model-Context-Protocol (MCP) implementation for a calculator service that uses Claude AI to process natural language requests and perform mathematical calculations.

Architecture

The service consists of three main components:

Calculator API (calculator-api.js): Handles basic mathematical operations
MCP Server (mcp-server.js): Manages LLM integration and tool orchestration
MCP Client (mcp-client.js): Provides a user interface for interacting with the service

Setup

Install dependencies:

npm install

Create a .env file in the root directory with the following variables:

ANTHROPIC_API_KEY=your_api_key_here
PORT=3000
MCP_PORT=3001

Running the Service

You can run all components concurrently:

npm start

Or run them individually:

# Calculator API
npm run start:calculator

# MCP Server
npm run start:mcp

# MCP Client
npm run start:client

Usage

Once the service is running, you can interact with it through the client interface. Here are some example commands:

"Add 5 and 3"
"What is 10 plus 20?"
"Calculate 7.5 + 2.25"
"Multiply 4 by 6"
"What is 8 times 3?"

Type "help" for more examples or "exit" to quit.

API Endpoints

Calculator API (Port 3000)

POST /:operation - Perform mathematical operations (add, subtract, multiply, divide, power)
GET /health - Health check endpoint

MCP Server (Port 3001)

GET /tools - List available tools
POST /execute/:toolId - Execute a specific tool
POST /agent - Process natural language requests
GET /health - Health check endpoint

Error Handling

The service includes comprehensive error handling for:

Invalid mathematical operations
Division by zero
Invalid parameter types
LLM response parsing errors
Network errors

Dependencies

@anthropic-ai/sdk: ^0.51.0
axios: ^1.6.7
body-parser: ^1.20.2
cors: ^2.8.5
dotenv: ^16.4.5
express: ^4.18.3
concurrently: ^8.2.2 (dev dependency)