mcp-adder

AshishSinha5/mcp-adder

3.2

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This document provides a structured overview of a Model Context Protocol (MCP) server designed to perform addition operations.

Python FastMCP OpenRouter

MCP Adder Demo

Minimal example showing a FastMCP server that adds two numbers and a Python client that calls it over StreamableHTTP. Includes an OpenRouter (generic LLM) client example for tool-calling.

MCP flow

Setup

  • Create and activate the venv (Python 3.10): python3.10 -m venv .venv && source .venv/bin/activate
  • Install deps: pip install -r requirements.txt
  • Set environment variables as needed (e.g., OPENROUTER_API_KEY in .env if you use OpenRouter).

Run the MCP server

source .venv/bin/activate
python add_server.py  # starts FastMCP with streamable-http on http://127.0.0.1:8000/mcp

Call the MCP tool from Python

source .venv/bin/activate
python test_mcp_call.py  # should print the sum from the MCP server

OpenRouter tool-call example

openrouter-client.py shows how to let a model call the add tool and then return a combined answer. Configure MODEL and OPENROUTER_API_KEY before running.

MCP UI [Optional]

You can also run the MCP UI to visualize tool calls:

npx -y @modelcontextprotocol/inspector

Then open in your browser: http://localhost:6274/?MCP_PROXY_AUTH_TOKEN=[your_token]