Mortgage data API endpoint on Base, paid per-call with USDC via x402.
What it does
This endpoint at lowpaymentfee.com provides mortgage-related data accessible via a POST request to `/api/v1/mortgages/20`. It is part of a broader platform (lowpaymentfee.com) that offers dozens of pay-per-call API endpoints spanning data analytics, AI/ML inference, finance, crypto, and utility services — all settled on the Base network using USDC through the x402 payment protocol.
The specific `/api/v1/mortgages/20` endpoint is listed as "Premium API Access" but its exact response schema and input parameters are not documented in the crawled material. The platform's landing page advertises a flat $0.02 per request across its other endpoints, but the x402 challenge for this particular endpoint shows a maxAmountRequired of 20,000 base units of USDC (6 decimals), which equals $0.02 — consistent with the site's advertised pricing. Payment is made via the x402 exact scheme with no API keys or rate limits required.
Documentation is extremely sparse. The /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 description of what mortgage data is returned or what inputs the endpoint expects. The endpoint is confirmed live (402 challenge captured), but without documentation it is difficult to know what data it actually provides.
Capabilities
Use cases
- —Retrieving mortgage-related data or calculations programmatically
- —Integrating mortgage information into financial dashboards or tools
- —Agent-driven mortgage data lookups with micropayments
Fit
Best for
- —Developers needing on-demand mortgage data without subscription commitments
- —AI agents that can pay per-call via x402/USDC on Base
- —Applications requiring keyless, instant-access financial APIs
Not for
- —Users who need detailed API documentation before integrating
- —High-volume consumers who need bulk pricing or rate-limit guarantees
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/mortgages/20 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>"Endpoint
Quality
The endpoint is confirmed live via a valid 402 x402 challenge, and pricing is clear ($0.02 USDC on Base). However, there is no documentation, no OpenAPI spec, no request/response schema, and no description of what the mortgage endpoint actually returns. The docs pages are empty. This is effectively a stub listing.
Warnings
- —No documentation available — /docs, /api, /pricing, and /README all return only a wallet-connect prompt with no content
- —No OpenAPI or schema describing request parameters or response format for /api/v1/mortgages/20
- —The endpoint name 'Premium API Access' is generic and does not describe the actual data returned
- —The '20' in the path is unexplained — it may be a mortgage term, an ID, or something else entirely
Citations
- —The platform advertises $0.02 per request with no API keys, no rate limits, and instant access on the Base networkhttps://lowpaymentfee.com
- —The x402 challenge shows maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/mortgages/20
- —Documentation pages (/docs, /api, /pricing, /README) contain only a 'Connect wallet' prompt with no substantive contenthttps://lowpaymentfee.com/docs