Pay-per-call ACH endpoint on Base via x402 — $0.02/request in USDC, no API keys required.
What it does
This endpoint at `/api/v1/ach/131` is part of the lowpaymentfee.com platform, which offers a collection of pay-per-request APIs spanning data analytics, AI/ML inference, finance, crypto, and utility services. All endpoints use the x402 payment protocol, settling in USDC on the Base network. The specific function of the `/api/v1/ach/131` path is not documented — the listing title is simply "Premium API Access" and the endpoint sits under an `/ach/` path segment, which may relate to ACH (Automated Clearing House) banking or payment processing, but this is unconfirmed.
Pricing is $0.02 per request (20,000 base units of USDC with 6 decimals = $0.02). Payment is handled inline via the x402 `X-PAYMENT` header — no API keys, accounts, or rate limits are advertised. The x402 challenge was successfully captured, confirming the endpoint is live and accepting POST requests. The payment recipient address is `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` and the USDC asset contract is `0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913` on Base.
Documentation is extremely sparse. The site's docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI schema, no request/response examples, and no description of what data this specific endpoint returns or what parameters it accepts. The broader site lists many endpoints at $0.02 each but provides no detail on any of them beyond category labels.
Capabilities
Use cases
- —Programmatic access to an ACH-related service with per-call USDC payment
- —Agent-driven API consumption without pre-registration or API keys
- —Integrating pay-as-you-go endpoints into automated workflows
Fit
Best for
- —Developers wanting zero-signup, pay-per-call API access
- —AI agents that can settle x402 payments in USDC on Base
- —Prototyping with low-cost per-request pricing
Not for
- —Users who need detailed API documentation or request/response schemas before integrating
- —High-volume production use cases where lack of documented SLAs or rate limits is a concern
- —Anyone needing non-crypto payment methods
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/ach/131 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>" \
-d '{}'Endpoint
Quality
The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02 USDC on Base), but there is zero documentation on what this endpoint does, what parameters it accepts, or what it returns. No OpenAPI schema, no examples, and the docs pages are empty. The specific purpose of /api/v1/ach/131 is unknown.
Warnings
- —The exact function of /api/v1/ach/131 is undocumented — the 'ach' path segment suggests ACH banking but this is unconfirmed
- —All documentation pages (docs, API, pricing, README) render only 'Connect wallet' with no usable content
- —No request or response schema is available; callers have no way to know what parameters to send
- —The site lists many endpoints but none appear to have detailed documentation
Citations
- —Endpoint returns 402 with x402 challenge, confirming it is livehttps://lowpaymentfee.com/api/v1/ach/131
- —Price is $0.02 per request (maxAmountRequired 20000 base units USDC, 6 decimals)https://lowpaymentfee.com/api/v1/ach/131
- —USDC asset contract on Base: 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/ach/131
- —Site advertises $0.02/request, no API keys, no rate limits, instant access on Base networkhttps://lowpaymentfee.com
- —Documentation pages render only 'Connect wallet' with no further contenthttps://lowpaymentfee.com/docs