Loan math for AI assistants.
One free MCP endpoint. Your assistant gets mortgage, refinance, and auto loan answers computed by full amortization, and every answer carries a link that opens the loan.tools calculator with those exact numbers loaded.
https://www.loan.tools/api/mcp
streamable HTTP · no key, no signup
Tools
| mortgage_payment | Monthly payment with PMI, taxes, insurance, HOA. Lifetime interest and payoff date. |
| compare_loans | Two scenarios side by side with the monthly and lifetime interest deltas. |
| refinance_breakeven | Monthly saving, the month closing costs are recovered, and a warning when a longer term hides a higher lifetime cost. |
| auto_loan | Car payments with each state's actual vehicle tax rules: CA, HI, VA, and DC tax the full price with no trade-in credit, MI caps the credit, SC caps the tax, and GA, NC, and VA tax vehicles outside the general sales tax. |
| extra_payment_impact | Months cut from the loan and interest saved by paying extra principal. |
Add it to your assistant
Claude Code
claude mcp add loantools --transport http https://www.loan.tools/api/mcpClick to copy
Claude Desktop and claude.ai
Settings > Connectors > Add custom connector > https://www.loan.tools/api/mcpClick to copy the URL path
Cursor and other MCP clients
{
"mcpServers": {
"loantools": { "url": "https://www.loan.tools/api/mcp" }
}
}
Click to copy
ChatGPT
Settings > Apps & Connectors > Advanced > Developer mode, then add https://www.loan.tools/api/mcpClick to copy the URL path
The fine print
- Free, read only, rate limited. Nothing about a request is stored, same as the rest of the site.
- Every formula the server runs is published at loan.tools/how-we-calculate.
- Tax figures are estimates from state rates and average local add-ons. County rates vary, and the tools accept an exact rate override.
- Questions or a tool you want added: contact@loan.tools.
Built by loan.tools · calculators for mortgages, refinancing, auto, student, and lease · pages for loan officers