Loan amortization schedule API, pay-per-call at $0.02 via USDC on Base.
What it does
This x402-enabled endpoint at lowpaymentfee.com returns a loan amortization schedule for a specific loan (loan ID 7 in the URL path). It is part of a broader platform offering dozens of pay-per-request APIs spanning data analytics, AI/ML inference, finance, crypto, and utility services — all priced at $0.02 per request with no API keys, no rate limits, and no commitments.
The endpoint accepts POST requests and is gated by the x402 payment protocol. Callers must include an X-PAYMENT header containing a valid payment proof. Payment settles in USDC on the Base network (token contract 0x8335…2913). The max amount required is 20,000 base units of USDC (6 decimals), which equals $0.02 per call. The response MIME type is application/json.
Documentation beyond the landing page is extremely sparse — the /docs, /api, /pricing, and /README pages all render only a "Connect wallet" prompt with no additional technical detail. There is no OpenAPI spec, no request/response schema, and no example payloads available. The endpoint is confirmed live (returns a proper 402 challenge), but the lack of documentation means callers must experiment to discover the expected POST body and response shape.
Capabilities
Use cases
- —Generating an amortization schedule for a loan to see principal and interest breakdowns per period
- —Integrating loan schedule data into a financial planning agent or dashboard
- —Programmatically retrieving payment schedules without API key registration
Fit
Best for
- —Agents needing on-demand loan amortization data with no signup
- —Developers prototyping financial tools who want instant pay-per-call access
- —Crypto-native applications that can settle micropayments in USDC on Base
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —High-volume batch processing where $0.02 per call adds up significantly
- —Applications requiring customizable loan IDs (the endpoint path is hardcoded to loan 7)
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/loans/7/schedule \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge with clear pricing, but there is no OpenAPI spec, no request/response schema, no examples, and all documentation pages render only a wallet-connect prompt. The specific purpose (loan 7 schedule) is narrow and undocumented.
Warnings
- —No OpenAPI spec or request/response schema available
- —All documentation pages (/docs, /api, /pricing, /README) render only 'Connect wallet' with no content
- —The endpoint path is hardcoded to loan ID 7 — unclear if other loan IDs are supported or how to parameterize
- —No example request body or response body could be found
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/loans/7/schedule
- —All APIs on the platform are priced at $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/loans/7/schedule