Loan amortization schedule API, pay-per-request via x402 on Base (USDC).
What it does
This endpoint at lowpaymentfee.com returns a loan amortization schedule for a specific loan (loan ID 17 in this URL path). It is part of a broader platform offering dozens of pay-per-call APIs spanning data analytics, AI/ML inference, finance, crypto, and utility services — all gated behind the x402 payment protocol on the Base network using USDC.
The endpoint accepts POST requests and returns JSON. Each call costs $0.02 in USDC (20,000 base units with 6 decimals) settled on-chain via the x402 "exact" payment scheme to the provider's wallet. There are no API keys, no rate limits, and no subscription commitments — you simply attach an X-PAYMENT header with a valid x402 payment proof.
Documentation is extremely sparse. The crawled /docs, /api, /pricing, and /README pages all returned only a "Connect wallet" prompt with no substantive content. There is no OpenAPI spec, no request/response schema, and no examples available. The specific input parameters for the loan schedule endpoint (e.g., whether you can customize loan terms, interest rates, or payment frequency via the POST body) are unknown. The endpoint is confirmed live via a 402 challenge response.
Capabilities
Use cases
- —Generating an amortization schedule for a loan to see principal and interest breakdowns per period
- —Integrating loan schedule data into a fintech application without managing API keys
- —Agent-driven financial planning that needs on-demand loan payment calculations
Fit
Best for
- —Developers needing quick, keyless access to loan amortization data
- —AI agents that can settle micropayments on Base for financial computations
- —Applications requiring pay-as-you-go loan schedule lookups
Not for
- —Users who need detailed API documentation or request/response schemas before integrating
- —High-volume batch processing where $0.02 per request adds up significantly
- —Users without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/loans/17/schedule \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>"Endpoint
Quality
The endpoint is confirmed live via a valid 402 challenge, but there is no documentation, no OpenAPI spec, no request/response schema, and no examples. The loan schedule endpoint's input parameters and output format are entirely unknown. The site's doc pages are all empty 'Connect wallet' stubs.
Warnings
- —No API documentation available — all doc pages return only 'Connect wallet' with no content
- —No OpenAPI or schema definition found; request body parameters are unknown
- —Response format and fields are completely undocumented
- —The endpoint path references a hardcoded loan ID (17); it is unclear whether this is parameterizable or what it represents
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units in USDC on Base networkhttps://lowpaymentfee.com/api/v1/loans/17/schedule
- —The platform advertises $0.02 per request pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset contract on Base: 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/loans/17/schedule