Data source: Standard amortization formulas
https://context.gnist.ai/rest/mortgage-calculator/
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Tools (4)
calculate_monthly_paymentCalculate fixed monthly mortgage payment.
Given a loan amount, interest rate, and term, computes the monthly payment,
total amount paid over the life of the loan, and total interest.
| Parameter | Type | Required | Description |
|---|---|---|---|
principal | number | required | Loan amount. |
annual_rate | number | required | Annual interest rate as a percentage (e.g. 5.5 for 5.5%). |
term_years | integer | required | Loan term in years. |
{
"principal": 1.0,
"annual_rate": 1.0,
"term_years": 1
}calculate_amortizationGenerate a full amortization schedule for a mortgage.
Returns monthly entries showing how each payment splits between principal
and interest, plus the remaining balance after each payment.
| Parameter | Type | Required | Description |
|---|---|---|---|
principal | number | required | Loan amount. |
annual_rate | number | required | Annual interest rate as a percentage (e.g. 5.5 for 5.5%). |
term_years | integer | required | Loan term in years. |
{
"principal": 1.0,
"annual_rate": 1.0,
"term_years": 1
}calculate_affordabilityEstimate how much home a buyer can afford.
Uses the 28% front-end DTI ratio: maximum housing payment is 28% of gross
monthly income, minus existing debts.
| Parameter | Type | Required | Description |
|---|---|---|---|
annual_income | number | required | Gross annual income. |
annual_rate | number | required | Annual interest rate as a percentage (e.g. 5.5 for 5.5%). |
monthly_debts | number | optional | Existing monthly debt obligations. (default: 0.0) |
down_payment | number | optional | Cash available for down payment. (default: 0.0) |
term_years | integer | optional | Loan term in years. (default: 30) |
{
"annual_income": 1.0,
"annual_rate": 1.0
}report_feedbackReport a bug, feature request, or general feedback for this data source.
Use this when something doesn't work as expected, when you'd like
a new feature, or when you have suggestions for improvement.
Args:
feedback: Describe the issue or suggestion.
feedback_type: One of 'bug', 'feature_request', or 'general'.
| Parameter | Type | Required | Description |
|---|---|---|---|
feedback | string | required | |
feedback_type | string | optional | (default: "general") |
{
"feedback": "example"
}Quick Start
curl -X POST "https://context.gnist.ai/rest/mortgage-calculator/calculate_monthly_payment" \
-H "Content-Type: application/json" \
-H "Gnist-API-Key: YOUR_API_KEY" \
-d '{"principal": 1.0, "annual_rate": 1.0, "term_years": 1}'
import httpx
resp = httpx.post(
"https://context.gnist.ai/rest/mortgage-calculator/calculate_monthly_payment",
headers={"Gnist-API-Key": "YOUR_API_KEY"},
json={
"principal": 1.0,
"annual_rate": 1.0,
"term_years": 1
},
)
print(resp.json())