Skip to main content
Glama
rubensgomes

calculator-mcp

by rubensgomes
OverviewSchemaRelated ServersScoreDiscussions
Python
Hybrid

Calculator MCP Server

An MCP (Model Context Protocol) server that exposes calculator operations as tools. Each tool delegates computation to the calculator-lib-rubens library.

Features

16 calculator tools available via MCP:

Two-operand operations: add, subtract, multiply, divide, power, nth_root, modulo, floor_divide

Single-operand operations: sqrt, absolute, floor, ceil, log10, ln, exp

Rounding: round_number (with configurable decimal places)

Related MCP server: Math Expression MCP Server

Prerequisites

  • Python 3.14+

  • Poetry for dependency management

Installation

poetry install

Configuration

The server ships with a default config.yaml bundled inside the package. To override it, set the CALCULATOR_MCP_CONFIG environment variable to the absolute path of your custom configuration file:

export CALCULATOR_MCP_CONFIG=/path/to/your/config.yaml

When CALCULATOR_MCP_CONFIG is not set, the bundled default is used automatically.

The configuration file has two sections:

server:
    transport: "http"     # "stdio" or "http"
    host: "127.0.0.1"     # Host for HTTP transport
    port: 9000            # Port for HTTP transport
    timeout: 10           # Tool execution timeout in seconds

client:
    is_oauth: false                        # Enable OAuth authentication
    url: "http://127.0.0.1:9000/mcp"       # Server URL for HTTP transport
    token_dir: "/home/user/.fastmcp"       # OAuth token storage directory
    callback_port: 10000                   # OAuth callback server port

The logging section controls Python logging via dictConfig. The default configuration logs calculator_mcp messages at INFO level to stderr.

Running the Server

There are three ways to start the server:

Console script (installed by Poetry):

# requires poetry to be installed
poetry install # only needed once
poetry run calculator-mcp

As a Python module:

# requires poetry to be installed
poetry install # only needed once
eval $(poetry env activate)
python -m calculator_mcp
deactivate

With a custom configuration:

# requires poetry to be installed
poetry install # only needed once
export CALCULATOR_MCP_CONFIG=/path/to/your/config.yaml
poetry run calculator-mcp

Running the Client

A sample integration test client is provided in tests/integration/client.py to demonstrate the MCP protocol with the server. It lists all available tools and calls each one with sample arguments.

Important: The server must be running before you start the client. See Running the Server above.

Run the client:

# requires poetry to be installed
poetry install # only needed once
eval $(poetry env activate)
python tests/integration/client.py
deactivate

Add MCP Server to Claude Code

  • Add the MCP server to Claude Code using project scope. The file .mcp.json is added to the project root folder:

    # It is assumed that the MCP server is running on http://127.0.0.1:9000
cd $(git rev-parse --show-toplevel) || exit
claude mcp add \
    --scope project \
    --transport http \
    calculator-mcp http://127.0.0.1:9000/mcp

Style Guide

This project follows the Google Python Style Guide. All docstrings use the Google format with Args:, Returns:, and Raises: sections where applicable. Compliance is enforced via pylint, black, isort, and mypy.

Development

# Run tests
poetry run pytest

# Run tests with coverage
poetry run pytest --cov

# Lint
poetry run pylint src/calculator_mcp

# Format code
poetry run black src tests
poetry run isort src tests

# Type check
poetry run mypy src/calculator_mcp

Project Structure

calculator-mcp/
├── pyproject.toml                 # Project metadata, dependencies, tool config
├── src/calculator_mcp/
│   ├── __init__.py
│   ├── __main__.py                # python -m calculator_mcp entry point
│   ├── config.py                  # Loads config.yaml, configures logging
│   ├── config.yaml                # Bundled default runtime config
│   ├── main.py                    # CLI entry point, signal handling
│   └── server.py                  # FastMCP server with 16 @mcp.tool functions
└── tests/
    ├── __init__.py
    ├── test_config.py             # Unit tests for config module
    ├── test_main.py               # Unit tests for main module
    ├── test_server.py             # Integration tests via MCP Client
    ├── test_tools.py              # Unit tests for tool functions
    └── integration/
        ├── __init__.py
        └── client.py              # Sample MCP client with OAuth support

License

See LICENSE for details.

This server cannot be installed

F
license - not found
-
quality - not tested
B
maintenance

How are these scores calculated?

Maintenance

–Maintainers
–Response time
2dRelease cycle
17Releases (12mo)
Commit activity

Resources

Unclaimed servers have limited discoverability.

Looking for Admin?

If you are the server author, to access and configure the admin panel.

Latest Blog Posts

MCP directory API

We provide all the information about MCP servers via our MCP API.

curl -X GET 'https://glama.ai/api/mcp/v1/servers/rubensgomes/calculator-mcp'

If you have feedback or need assistance with the MCP directory API, please join our Discord server