Axiom Calculator MCP

What vdalhambra/axiom-calculator-mcp MCP server does

The vdalhambra/axiom-calculator-mcp MCP server gives MCP-compatible AI clients access to eight personal finance calculations. It covers housing decisions, investment projections, retirement planning, financing comparisons, and debt repayment without requiring an API key.

The results are designed to answer practical questions such as the monthly cost of a mortgage, the long-term difference between renting and buying, the portfolio needed for financial independence, or the savings from making additional debt payments.

How it works

The server runs locally as a stdio process. An MCP client starts the package with uvx axiom-calculator-mcp, then exposes the calculator tools to the connected agent. Users provide the relevant financial assumptions in a prompt or tool call, and the server returns calculated figures and, for several tools, supporting tables or comparisons.

Calculations use the supplied values rather than an external data source. The package does not require API keys, accounts, or a separate hosted service. Its README also states that it has no rate limits.

Setup and configuration

For a client that supports stdio MCP servers, configure the server with the uvx runner and the axiom-calculator-mcp package:

{
  "mcpServers": {
    "calculator": {
      "command": "uvx",
      "args": ["axiom-calculator-mcp"]
    }
  }
}

Claude Desktop and Claude Code are documented setup targets. The repository also provides a direct uvx axiom-calculator-mcp command for other MCP clients that support stdio. From source, the README documents cloning the repository and running uv run axiom-calculator.

No environment variables or credentials are required. The project is released under the MIT license.

Tools and capabilities

The vdalhambra/axiom-calculator-mcp MCP server provides these tools:

• mortgage_calculator calculates principal-and-interest payments, lifetime interest, total home cost, break-even information, and the first 12 months of amortization. Property tax and insurance can optionally be included in the monthly total.
• rent_vs_buy compares renting and buying over a selected period, including rent increases, home appreciation, equity, and the opportunity cost of the down payment.
• compound_interest projects growth with optional recurring contributions and returns final value, contributions, interest, and annual results.
• fire_number estimates the portfolio required for financial independence and can estimate the time to reach it from current savings and annual savings.
• inflation_adjusted_return compares nominal investment growth with purchasing-power growth after inflation.
• loan_comparison compares two loans using payment, total cost, fees, term, and true APR.
• true_credit_cost estimates total cost and implied APR for financing products and fixed payment schedules.
• debt_payoff_plan compares a base repayment schedule with one that adds monthly payments, including time and interest savings.