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 16 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 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 a specified wallet address. The response MIME type is application/json. The endpoint accepts POST requests and is marked as discoverable.
The broader lowpaymentfee.com platform advertises uniform $0.02/request pricing across all endpoints, with no API keys, no rate limits, and instant access. However, documentation pages (/docs, /pricing, /README) returned only a "Connect wallet" prompt with no substantive content, so details about the loan schedule's input parameters, response schema, and the meaning of the loan ID path parameter are unknown. It is unclear whether loan ID 16 is a fixed demo resource or whether other loan IDs are available.
Capabilities
Use cases
- —Retrieving an amortization schedule showing principal and interest breakdowns for a loan
- —Integrating loan payment schedule data into financial planning tools
- —Agents autonomously fetching loan repayment details without API key management
Fit
Best for
- —Developers needing on-demand loan schedule data without subscription commitments
- —AI agents that can settle micropayments via x402 on Base
- —Applications requiring pay-per-use financial calculation endpoints
Not for
- —Users who need detailed API documentation or schema definitions before integrating
- —Bulk loan portfolio analysis requiring thousands of calls (no documented batch endpoint)
- —Users without a Base-network USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/loans/16/schedule \
-H "X-PAYMENT: <x402-payment-header>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, confirming pricing and settlement details. However, there is no documentation for the loan schedule endpoint specifically — no input schema, no response schema, no examples. The docs/pricing/README pages are empty. The endpoint path is hardcoded to loan ID 16 with no explanation of what that represents.
Warnings
- —No API documentation available — /docs, /pricing, and /README pages all return only a wallet-connect prompt with no content
- —No input or output schema documented for the loan schedule endpoint
- —Loan ID 16 is hardcoded in the endpoint path; it is unclear if other loan IDs exist or how to create them
- —The endpoint's relationship to the broader platform's advertised categories (AI, analytics, etc.) is unclear — this specific path is not listed on the homepage
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/loans/16/schedule
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —USDC asset contract on Base: 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/loans/16/schedule