Developers

Budget Build Invest! exposes two developer surfaces: embeddable calculator widgets and a Node.js MCP server.

Embeddable widgets

Embed any calculator on your site with a single iframe:

<iframe
  src="https://budgetbuildinvest.com/embed/mortgage-calculator"
  width="100%"
  height="600"
  style="border:none;border-radius:12px"
  title="Mortgage Calculator"
></iframe>

Attribution link is included in the embed. No API key required.

MCP Server (Model Context Protocol)

Our Node.js MCP server exposes 6 finance calculation tools to AI assistants like Claude. All tools are powered by the same pure-math library used by our calculators.

Available tools

• calcMortgage — mortgage payment + amortization
• calcCompoundInterest — compound interest with contributions
• calcLoan — EMI + loan schedule
• calcDebtPayoff — snowball vs avalanche payoff
• calcRetirement — retirement nest egg projection
• calcNetWorth — net worth + debt-to-asset ratio

Open source

The finance math library (src/lib/finance/index.ts) and MCP server (mcp/) are available for review. Coming soon: npm package.

Contact

API partnership or integration inquiries: support.cosyslabs@gmail.com