Pay-per-call ACH endpoint on Base via x402 — $0.02/request in USDC, no API keys required.
What it does
lowpaymentfee.com hosts a collection of pay-per-request API endpoints gated by the x402 payment protocol on the Base network. The specific endpoint at `/api/v1/ach/42` is listed under "Premium API Access" and accepts POST requests. Payment is settled in USDC (contract 0x8335…2913 on Base) at a maximum cost of 20,000 base units, which equals $0.02 per call (USDC uses 6 decimals). No API keys, subscriptions, or rate limits are advertised — callers simply attach an X-PAYMENT header with a valid x402 payment proof.
The broader lowpaymentfee.com platform advertises endpoints across several categories: Data & Analytics (metrics, reports, data export, insights), AI & Machine Learning (sentiment analysis, text summarization, classification, embeddings), Finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and Infrastructure utilities (geocoding, validation, conversion, generation). All are priced at $0.02 per request. However, the specific endpoint `/api/v1/ach/42` does not clearly map to any of these documented categories — the "ach" path segment and the numeric ID "42" are not explained in the available documentation.
Documentation is extremely sparse. The /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 examples of what this endpoint accepts or returns. The endpoint is confirmed live (returns a proper 402 challenge), but without documentation it is unclear what data or functionality it provides.
Capabilities
Use cases
- —Accessing a premium ACH-related data or processing endpoint with per-call USDC micropayments
- —Integrating pay-per-use API calls into agent workflows without managing API keys
- —Settling API costs on-chain via the Base L2 network
Fit
Best for
- —Developers wanting keyless, pay-as-you-go API access
- —Agent-based systems that can handle x402 payment challenges natively
- —Users comfortable with USDC payments on Base
Not for
- —Anyone needing detailed API documentation or request/response schemas before integrating
- —Use cases requiring free or subscription-based access models
- —Users who cannot transact in USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/ach/42 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>" \
-d '{}'Endpoint
Quality
The endpoint is confirmed live with a valid x402 402 challenge, but documentation is effectively nonexistent — no OpenAPI spec, no request/response schema, no examples, and the /docs pages are empty. The purpose of the /api/v1/ach/42 path is unexplained and does not match any documented endpoint category. This is essentially a stub listing.
Warnings
- —The endpoint path /api/v1/ach/42 does not correspond to any documented API on the landing page — its purpose is unknown.
- —All documentation pages (/docs, /api, /pricing, /README) render only 'Connect wallet' with no usable content.
- —No request body schema or response schema is available; callers cannot know what to send or what to expect back.
- —The 'ach' path segment may relate to ACH bank transfers, which could involve regulated financial activity — exercise caution.
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units in USDC on Basehttps://lowpaymentfee.com/api/v1/ach/42
- —All listed APIs are priced at $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/ach/42
- —Documentation pages (/docs, /api, /pricing, /README) show only 'Connect wallet'https://lowpaymentfee.com/docs