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 79 in the URL path). It is part of a broader platform offering pay-per-call APIs across data analytics, AI/ML, finance, and utility categories, all settled via the x402 protocol on the Base network using USDC.
The endpoint is live and responds with a 402 Payment Required challenge, requesting an x402 payment of up to 20,000 base units of USDC (0.02 USD, since USDC uses 6 decimals) per request. Payment is made to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 on Base. The endpoint accepts POST requests and returns application/json. No API keys or rate limits are advertised; access is gated solely by the x402 micropayment.
Documentation is extremely sparse. The crawled docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no further content. The specific input schema for the loan schedule endpoint (e.g., what POST body fields are expected) and the response schema are not documented anywhere in the crawled material. The loan ID 79 is hardcoded in the URL, suggesting each loan may have its own endpoint path. Without further documentation it is unclear what parameters the POST body accepts or what the schedule response looks like.
Capabilities
Use cases
- —Retrieve a loan amortization schedule showing principal and interest breakdowns per period
- —Integrate loan payment data into financial dashboards or planning tools
- —Automate loan analysis workflows with per-call micropayments
Fit
Best for
- —Agents or apps needing on-demand loan schedule data without API key management
- —Developers building financial tools who prefer pay-per-use pricing
- —Crypto-native applications that can settle payments on Base
Not for
- —Users who need detailed API documentation or input/output schemas before integrating
- —Bulk loan portfolio analysis requiring thousands of calls (no documented batch endpoint)
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/loans/79/schedule \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402_payment_token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing ($0.02 USDC on Base). However, there is no documentation of input parameters, output schema, or examples. The docs/pricing/README pages are all empty beyond a wallet connect prompt. This is effectively a stub listing.
Warnings
- —No input schema documented — unknown what POST body fields the endpoint expects
- —No output schema or example response available
- —Docs, pricing, and README pages render no useful content (only 'Connect wallet')
- —Loan ID 79 is hardcoded in the path; unclear how to discover or create other loan IDs
- —The platform lists many API categories on its homepage but this specific loans endpoint is not listed among them
Citations
- —Endpoint returns 402 with x402 challenge requesting up to 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/loans/79/schedule
- —Platform advertises $0.02 per request, no API keys, no rate limits, Base networkhttps://lowpaymentfee.com
- —USDC asset contract on Base: 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/loans/79/schedule