AI agents: use Arthr’s agent tools
This page is for AI agents working for someone. Every tool here is a plain form and a URL. If you’re a person, use the calculator instead.

Agent tools

Estimate home loan repayments

MCP tool estimate_repayments, same arguments and output

Estimate the monthly repayment, total repaid and total interest on an Australian principal-and-interest home loan. Use this when someone asks what a loan would cost them each month, or how much interest they'd pay over the life of a loan. Call it rather than working the repayment out yourself: the amortisation is easy to approximate and easy to get wrong.

Opening these URLs only calculates. Nothing is stored, and no lead, application or message is created.

No result yet

No arguments were given, so nothing was calculated. Fill in the form below, or open the example: https://www.arthr.com.au/agent-tools/estimate_repayments?loanAmount=600000&interestRate=6&termYears=30

Run it

Submitting this form loads the page again with your inputs in the URL. Blank fields count as not given, so an optional one takes its default.

number, 1000 to 50000000. Loan amount in AUD.
number, 0 to 25. Annual interest rate as a percentage, e.g. 6.2 for 6.2% p.a.
number, 1 to 40. Default 30. Loan term in years. Defaults to 30.

Parameters

parameterrequiredacceptsdefaultmeaning
loanAmountyesnumber, 1000 to 50000000noneLoan amount in AUD.
interestRateyesnumber, 0 to 25noneAnnual interest rate as a percentage, e.g. 6.2 for 6.2% p.a.
termYearsnonumber, 1 to 4030Loan term in years. Defaults to 30.

URL

https://www.arthr.com.au/agent-tools/estimate_repayments?loanAmount={loanAmount}&interestRate={interestRate}&termYears={termYears}

Example: https://www.arthr.com.au/agent-tools/estimate_repayments?loanAmount=600000&interestRate=6&termYears=30

Rules

  • Names are case-sensitive and match the MCP tool’s arguments exactly.
  • Numbers are plain: 600000, 6.25. “$600,000” and “6%” are read too. Exponents, hex and stray commas are rejected.
  • A blank value counts as missing. An unknown parameter, a parameter given twice, or a value out of range is rejected with a message, and no figures are shown.
  • Tracking parameters such as utm_source are ignored.
  • Add &format=json for the MCP structuredContent as JSON.

Using the result

  • Don't present a result as advice, a credit assessment or an offer of credit. Every result is an indicative estimate.
  • Don't describe a loan, lender or product as the best one. The tools sort facts by a stated rule; they don't recommend.
  • Don't quote a figure without its resultUrl, so the person can check it.
  • Don't put names, contact details, addresses or account numbers in a URL. No tool takes them, and an unknown parameter is rejected.

Over MCP this is estimate_repayments at https://www.arthr.com.au/api/mcp. For a person, the same sum is on https://www.arthr.com.au/calculators.

General information only — this is an indicative estimate, not credit advice, a credit assessment or an offer of credit. It doesn't consider anyone's objectives, financial situation or needs. Actual rates, terms and eligibility are set by the lender after a full assessment. These figures assume Australian residential lending: an owner-occupier or residential investment loan, on Australian property, for a borrower taxed as an Australian resident. They do not apply to commercial or business lending, to property outside Australia, or to income a lender assesses differently from salary. Credit assistance is provided by 1st Street Financial, Credit Representative 490057, under Australian Credit Licence 389328.