Calcnook MCP Server

What Declan142/calcnook-mcp-server MCP server does

Declan142/calcnook-mcp-server MCP server wraps the open-source calcnook calculation engine and exposes 17 tools through the Model Context Protocol. Its scope covers common personal finance calculations, selected country-specific taxes and employment benefits, Islamic finance formulas, health metrics, currency display, and Indian utility billing.

The financial planning tools calculate compound growth, SIP or DCA contributions, loan and mortgage payments, retirement targets, and safe withdrawals based on the 4% rule. Health calculations cover BMI with WHO categorization, Mifflin-St Jeor BMR, and TDEE. Currency conversion accepts rates supplied by the caller, while currency formatting includes Indian lakh and crore representations.

Islamic finance support includes Zakat with a nisab check, Murabaha, Ijarah, Mudarabah, Hajj savings, and AAOIFI-oriented halal stock screening based on supplied financial ratios. Regional tools cover income tax for the US, UK, Canada, Australia, and India for 2026; UAE and Saudi VAT; UAE or Saudi End of Service Gratuity; Saudi or GCC national Zakat estimates; and Indian electricity bills using BESCOM, MSEB, BSES, or custom slabs.

How it works

The server communicates with MCP-compatible clients and delegates requests to deterministic calculation functions in the calcnook engine. Inputs such as principal, contribution amount, rate, duration, salary, country, or financial statement values are provided in each tool call. Currency conversion does not fetch live rates: the caller must provide the exchange rate to use.

Because the calculations run locally and the project describes itself as using the Python standard library, the server does not need an external API credential. Results depend on the supplied inputs, selected country or preset, and the calculation assumptions represented by the relevant tool.

Setup and configuration

Declan142/calcnook-mcp-server can be started without a separate application setup using:

uvx calcnook-mcp

A pip-based installation is also documented:

pip install calcnook-mcp
calcnook-mcp

For Claude Desktop or Claude Code, configure an MCP entry with uvx as the command and calcnook-mcp as its argument. Cursor can use the same MCP configuration pattern. The README also states that Goose and Continue can use the same JSON block in their respective MCP configuration sections.

Tools and capabilities

The available tools include:

• Compound-interest projections for a lump sum.
• SIP or DCA schedules with optional annual increases.
• Loan and mortgage amortization with optional extra payments.
• Retirement corpus, required monthly SIP, and withdrawal calculations.
• BMI, BMR, and TDEE calculations.
• Caller-rated currency conversion and currency formatting.
• Zakat, Islamic financing, Hajj savings, and halal stock screening.
• Country-specific income tax, VAT, gratuity, and Saudi Zakat estimates.
• Indian electricity billing with named distribution-company presets or custom slabs.

Limitations and notes

The server calculates from supplied values; it is not described as a live market-rate, tax-filing, or utility-billing data service. In particular, currency conversion requires the caller to provide rates. Country-specific tax calculations are listed for 2026 and should be matched to the supported country options rather than assumed to cover other jurisdictions. Indian electricity calculations depend on the selected preset or custom slab configuration. The project is licensed under MIT.