30-year mortgage data endpoint, pay-per-call via x402 on Base (USDC).
What it does
This endpoint at `/api/v1/mortgages/30` is part of the lowpaymentfee.com platform, which offers a collection of pay-per-request APIs settled via the x402 protocol on the Base network using USDC. The specific endpoint appears to serve 30-year mortgage-related data (likely rate or payment calculations), though the exact response schema is not documented in the available crawl material.
The endpoint is live and returns a valid x402 challenge. The price per request is $0.02 USDC (maxAmountRequired of 20,000 base units at 6 decimals). Payment is made via the x402 "exact" scheme to the specified wallet address on Base. No API keys or rate limits are advertised — access is gated purely by micropayment. The platform lists many other endpoints across finance, AI, data analytics, and utility categories, all at the same $0.02/request price point.
Documentation is extremely sparse. The docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no substantive content. There is no OpenAPI spec, no request/response schema, and no example payloads available. The endpoint's exact input parameters and output format must be discovered experimentally.
Capabilities
Use cases
- —Fetching current 30-year mortgage rate data for financial applications
- —Integrating mortgage information into real estate or lending tools
- —Automated mortgage rate monitoring by AI agents
Fit
Best for
- —Developers needing on-demand mortgage data without API key management
- —AI agents that can settle x402 micropayments on Base
- —Applications requiring simple pay-per-call access to financial data
Not for
- —Users who need detailed documentation or guaranteed SLAs before integrating
- —High-volume consumers who would prefer bulk/subscription pricing
- —Anyone unable to transact in USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/mortgages/30 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, confirming it exists and is gated by payment. However, there is no documentation, no OpenAPI spec, no request/response schema, and no examples. The endpoint's actual functionality (what it returns for 30-year mortgages) is entirely inferred from the URL path. Docs pages are empty stubs.
Warnings
- —No documentation available — docs, API, pricing, and README pages all show only 'Connect wallet' with no content.
- —No request or response schema provided; input parameters and output format are unknown.
- —Endpoint functionality inferred solely from URL path '/api/v1/mortgages/30'; actual behavior unverified.
- —This endpoint is not listed on the provider's homepage among their advertised APIs.
Citations
- —The endpoint returns a valid x402 challenge with maxAmountRequired of 20000 base units in USDC on Basehttps://lowpaymentfee.com/api/v1/mortgages/30
- —The platform advertises $0.02/request pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/mortgages/30