Loan amortization schedule API, pay-per-call at $0.02 via USDC on Base.
What it does
This x402-enabled endpoint at lowpaymentfee.com returns a loan amortization schedule for a specific loan (loan ID 36 in the URL path). It is part of a broader platform offering dozens of pay-per-request APIs spanning data analytics, AI/ML inference, finance, crypto, and utility services — all priced at $0.02 per request and settled in USDC on the Base network via the x402 protocol.
The endpoint accepts POST requests and returns JSON. The x402 challenge confirms the endpoint is live, requiring a maximum of 20,000 base units of USDC (0.02 USD, since USDC uses 6 decimals) per call, paid to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3. No API keys or rate limits are advertised; access is gated purely by the x402 payment header.
Documentation is extremely sparse. The crawled /docs, /api, /pricing, and /README pages all returned only a "Connect wallet" prompt with no substantive content. There is no OpenAPI spec, no request/response schema documentation, and no examples of what fields the POST body should contain or what the schedule response looks like. The endpoint path suggests it computes or retrieves an amortization schedule for loan ID 36, but the input parameters and output format are unknown.
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 loan analysis workflows that pay per API call without API keys
Fit
Best for
- —Developers needing on-demand loan schedule data without subscription commitments
- —AI agents that can settle micropayments in USDC on Base
- —Quick prototyping of financial tools with zero signup friction
Not for
- —Production use requiring documented request/response schemas and SLAs
- —Bulk loan portfolio analysis where per-call pricing would be expensive
- —Users without USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/loans/36/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. However, there is no documentation, no OpenAPI spec, no request/response examples, and the crawled doc pages are empty. The specific purpose (loan 36 schedule) is only inferable from the URL path. This is effectively a stub listing.
Warnings
- —No documentation available — /docs, /api, /pricing, and /README pages all return only a wallet connect prompt with no content.
- —No OpenAPI or schema definition found; request body parameters and response format are completely unknown.
- —The endpoint path is hardcoded to loan ID 36; it is unclear whether other loan IDs are supported or how loans are created.
- —The platform lists many API categories (AI, analytics, finance, infrastructure) but none have visible documentation, raising questions about maturity.
Citations
- —Endpoint returns HTTP 402 with x402 challenge requiring 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/loans/36/schedule
- —Platform advertises $0.02 per request pricing 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/36/schedule
- —Docs, API, pricing, and README pages return only a Connect wallet prompt with no substantive documentationhttps://lowpaymentfee.com/docs