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 6) via a POST request. It is part of a broader platform offering pay-per-call APIs across data analytics, AI/ML, finance, and utility categories, all settled on-chain using the x402 protocol on the Base network with USDC.
The specific endpoint `/api/v1/loans/6/schedule` is priced at $0.02 per request (20,000 base units of USDC with 6 decimals). Payment is handled via the x402 `exact` scheme — callers attach an `X-PAYMENT` header with a signed payment payload, and the server returns the result in `application/json`. No API keys, rate limits, or upfront commitments are required; access is instant once payment is included.
Documentation on the site is extremely sparse — the docs, pricing, API, and README pages all render only a "Connect wallet" prompt with no additional technical content. The loan schedule endpoint itself is not listed on the homepage's catalog of available APIs, which raises questions about discoverability and whether this is a demo or production resource. There is no OpenAPI schema, no request/response examples, and no description of what fields the schedule contains or what input parameters the POST body expects. Treat this as a minimally documented endpoint.
Capabilities
Use cases
- —Retrieving an amortization schedule for a loan to display payment breakdowns
- —Integrating loan schedule data into a financial planning application
- —Agent-driven loan analysis workflows that pay per call with USDC
Fit
Best for
- —Developers needing on-demand loan schedule data without API key signup
- —AI agents that can settle micropayments on Base via x402
- —Prototyping financial tools with instant, keyless API access
Not for
- —Production use requiring documented request/response schemas and SLAs
- —Bulk loan portfolio analysis (no batch endpoint or rate-limit info available)
- —Users who cannot transact in USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/loans/6/schedule \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live (returns a valid 402 x402 challenge), but there is no documentation, no OpenAPI schema, no request/response examples, and the endpoint is not even listed in the site's own API catalog. Effectively a stub listing.
Warnings
- —No OpenAPI or schema documentation available for this endpoint
- —Docs, pricing, API, and README pages all render only 'Connect wallet' with no content
- —This specific loans endpoint is not listed on the provider's homepage API catalog — unclear if it is a demo or production resource
- —Request body format and response schema are completely unknown
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/loans/6/schedule
- —The platform advertises $0.02 per request pricing with no API keys, no rate limits, and instant access on the Base networkhttps://lowpaymentfee.com
- —The USDC asset address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/loans/6/schedule