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 67) 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 x402 challenge confirms the endpoint is live and accepts payments of up to $0.02 per request (20,000 base units of USDC with 6 decimals = $0.02). Payment is made via the x402 exact scheme to a specified wallet address, with a 300-second timeout. The response MIME type is application/json. No API keys or rate limits are advertised; access is gated purely by micropayment.
Documentation is extremely sparse. The crawled docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI spec, no request/response schema, and no example payloads available. The specific loan schedule endpoint path includes a hardcoded loan ID (67), and it is unclear whether this is a demo resource or whether other loan IDs are available. The input schema and expected POST body fields (e.g., loan parameters) are not documented anywhere in the crawled material.
Capabilities
Use cases
- —Retrieving a loan amortization schedule showing principal and interest breakdowns per period
- —Integrating loan payment calculations into financial planning tools
- —Agent-driven financial analysis requiring on-demand loan schedule data
Fit
Best for
- —Developers needing on-demand loan schedule data without API key management
- —AI agents that can settle x402 micropayments on Base for financial data
- —Applications requiring pay-per-use loan amortization without subscriptions
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —Bulk loan schedule generation across many loan IDs (no batch endpoint documented)
- —Users without USDC on Base network for payment
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/loans/67/schedule \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402_payment_token>"Endpoint
Quality
The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02/request in USDC on Base). However, there is no OpenAPI spec, no request/response schema, no documentation beyond a wallet-connect prompt, and no examples. The endpoint path contains a hardcoded loan ID with no explanation. This is effectively a stub listing.
Warnings
- —No API documentation available — docs, API, pricing, and README pages all show only 'Connect wallet'
- —No OpenAPI or JSON schema for request or response bodies
- —Endpoint path includes hardcoded loan ID (67); unclear if other loan IDs are supported or how to create loans
- —No examples of request payloads or response structures available anywhere in crawled content
- —POST body parameters are completely unknown
Citations
- —Endpoint returns 402 with x402 challenge accepting USDC on Base network, maxAmountRequired 20000 base unitshttps://lowpaymentfee.com/api/v1/loans/67/schedule
- —Platform advertises $0.02 per request pricing with no API keys, no rate limits, instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/loans/67/schedule