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 48 in this URL path). It is part of a broader platform offering various pay-per-call APIs spanning data analytics, AI/ML inference, finance, crypto, and utility services — all settled via the x402 protocol on the Base network using USDC.
The endpoint is live and returns a 402 challenge requesting payment of up to 20,000 base units of USDC (0.02 USD, since USDC uses 6 decimals) per request. Payment is made via the x402 "exact" scheme to the specified wallet address on Base. The endpoint accepts POST requests and returns JSON. No API keys or rate limits are advertised; access is gated purely by micropayment.
Documentation beyond the landing page 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 documentation, and no examples of what the loan schedule response looks like. The specific loan ID (48) is hardcoded in the URL, and it is unclear whether other loan IDs are available or how loan parameters are configured. The endpoint's actual utility and response format must be inferred.
Capabilities
Use cases
- —Retrieving a loan amortization schedule showing payment breakdowns over time
- —Integrating loan schedule data into financial planning tools or dashboards
- —Agent-driven financial calculations that need structured loan repayment data
Fit
Best for
- —Developers needing on-demand loan schedule data without API key management
- —AI agents that can settle x402 micropayments for financial data
- —Quick one-off loan amortization lookups at $0.02 per call
Not for
- —Bulk or high-volume loan schedule generation (no documented batch support)
- —Users who need detailed documentation or request/response schemas before integrating
- —Custom loan parameter configuration (the loan ID appears hardcoded in the path)
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/loans/48/schedule \
-H "X-PAYMENT: <x402-payment-token>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, but there is no OpenAPI spec, no request/response schema, no documentation beyond a landing page, and no examples. The loan ID is hardcoded with no explanation. The docs pages are all empty wallet-connect prompts. This is effectively a stub listing.
Warnings
- —No OpenAPI spec or request/response schema available
- —Documentation pages (/docs, /api, /pricing, /README) are all empty — only show 'Connect wallet'
- —Loan ID 48 is hardcoded in the URL; unclear how to access other loans or configure parameters
- —No example responses available to verify what the endpoint actually returns
- —The broader platform lists many endpoints but none have documented schemas
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/loans/48/schedule
- —Platform pricing is $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/loans/48/schedule