RupeeKit for AI assistants and developers

Calculator API and MCP documentation

Use the 6-calculator sourced pilot through one read-only JSON API or MCP endpoint. Calculator inputs, defaults, limits, output names, methodology, assumptions, canonical page, reviewed date, sources, privacy note, and disclaimer are returned in machine-readable form.

JSON API endpoints

Method	Endpoint	Purpose
GET	`/api/v1/calculators`	List every calculator in the reviewed pilot and its exact input contract.
GET	`/api/v1/calculators/{slug}`	Get one calculator’s inputs, defaults, output fields, methodology and sources.
POST	`/api/v1/calculators/{slug}`	Run the calculator. Send numeric values inside an `inputs` object.

REST calculation example

POST https://www.rupeekit.co.in/api/v1/calculators/personal-loan-true-apr-calculator-india
Content-Type: application/json

{
  "inputs": {
    "principal": 500000,
    "annualInterestRate": 12,
    "tenureMonths": 36,
    "processingFeePercent": 2,
    "gstPercent": 18,
    "insuranceAndOtherUpfront": 5000,
    "advanceEmis": 0
  }
}

Send application/json with a body no larger than 16 KiB. Inputs omitted from the request use documented defaults. Unknown keys, non-numeric values, out-of-range values, malformed JSON, unsupported media types and oversized payloads are rejected with structured errors.

MCP for AI tools

Beta JSON-RPC HTTP endpoint: https://www.rupeekit.co.in/api/mcp

Compatibility note: this beta currently advertises MCP protocol version 2025-03-26. Verification and transport hardening for the current 2025-11-25 specification are pending, so do not treat it as a production-SLA integration yet. Browser requests with a different Origin are rejected; non-browser clients should omit that header.

list_calculators discovers calculators and valid input fields.
get_calculator retrieves the complete contract for one slug.
calculate runs the selected calculator and returns structured results with sources.

MCP tool-call example

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "calculate",
    "arguments": {
      "slug": "emi-calculator-india",
      "inputs": {
        "principal": 500000,
        "annualRate": 12,
        "years": 3
      }
    }
  }
}

Instructions for AI assistants

Call list_calculators or get_calculator before calculating; never invent an input key.
Ask the user only for missing values that should not use the documented default.
Present the returned units and assumptions with the result.
Cite the returned canonical calculator URL and relevant official sources.
Preserve the returned disclaimer and never represent an estimate as personalized advice or guaranteed outcome.

Available calculators

This beta catalog is an explicit sourced pilot. Publishing a calculator on the website does not automatically expose it through REST or MCP; machine access is added only after contract and formula review.

Calculator	Slug	Inputs	API definition
Home Loan + SWP Stress Test India	`home-loan-swp-stress-test-india`	propertyPrice, downPayment, loanRate, loanYears, swpCorpus, expectedReturn, annualDrag, firstYearReturn, recoveryReturn, cashReserveMonths	JSON
Gratuity 2026 Old vs New Calculator	`gratuity-2026-old-vs-new-calculator-india`	monthlyRemuneration, currentBasicDa, newWageSharePercent, eligibleServiceYears, statutoryCap	JSON
Personal Loan True APR Calculator India	`personal-loan-true-apr-calculator-india`	principal, annualInterestRate, tenureMonths, processingFeePercent, gstPercent, insuranceAndOtherUpfront, advanceEmis	JSON
Invest vs Prepay Home Loan Calculator India	`invest-vs-prepay-home-loan-calculator-india`	outstandingPrincipal, loanRate, remainingMonths, lumpSum, expectedInvestmentReturn, annualDrag	JSON
Loan Foreclosure Net Savings Calculator India	`loan-foreclosure-net-savings-calculator-india`	outstandingPrincipal, annualInterestRate, remainingMonths, foreclosureFeePercent, gstPercent, alternativeReturn	JSON
Reduce EMI vs Tenure Calculator India	`reduce-emi-vs-tenure-calculator-india`	outstandingPrincipal, annualInterestRate, remainingMonths, prepaymentAmount	JSON

Data, privacy and responsible use

Only calculator inputs are accepted. Do not send PAN, Aadhaar, bank-account details or other sensitive information. Values are processed for the request and are not saved by default. Results are educational estimates—not personalized financial, tax, legal, lending or investment advice.