x402-gated premium API endpoint on Base, pay-per-call with USDC.
What it does
This endpoint at `/api/v1/ach/178` is part of the lowpaymentfee.com platform, which offers a broad catalog of x402-protocol pay-per-request APIs spanning data analytics, AI/ML inference, finance/Web3 data, and infrastructure utilities. The specific endpoint `/api/v1/ach/178` is listed under the title "Premium API Access" but its exact functionality is not documented — the path segment `ach/178` suggests it may relate to ACH (Automated Clearing House) payment processing or a specific resource identified by ID 178, but this is speculative.
The endpoint is live and returns a valid x402 challenge on POST. Payment is settled on the Base network using USDC (contract `0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913`) with an `exact` scheme. The maximum amount required is 20,000 base units, which at 6 decimals for USDC equals $0.02 per request — consistent with the platform's uniform $0.02/request pricing. No API keys are required; access is granted purely via the x402 payment header. The platform advertises no rate limits and instant access.
Documentation is extremely sparse. The docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no additional content. There is no OpenAPI schema, no request/response examples, and no description of what this specific endpoint accepts or returns beyond the generic "Premium API Access" label and `application/json` MIME type. Prospective users should be aware that the actual behavior of this endpoint is undocumented.
Capabilities
Use cases
- —Accessing a pay-per-request API endpoint without needing API key registration
- —Making programmatic payments for API access using USDC on Base
- —Integrating x402-protocol endpoints into agent workflows
Fit
Best for
- —Developers experimenting with x402 payment-gated APIs
- —Agents that can settle USDC payments on Base L2
- —Low-volume, pay-as-you-go API consumption without subscriptions
Not for
- —Users who need detailed API documentation before integrating
- —High-volume use cases where per-request pricing may not be cost-effective
- —Anyone who cannot transact in USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/ach/178 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>" \
-d '{}'Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, but there is zero documentation on what this specific endpoint does, what inputs it accepts, or what it returns. The path 'ach/178' is unexplained. No OpenAPI schema, no examples, and all doc pages are empty beyond a wallet connect prompt.
Warnings
- —Endpoint functionality is completely undocumented — the 'ach/178' path and 'Premium API Access' title give no actionable information about what the endpoint does.
- —All documentation pages (docs, API, pricing, README) render only 'Connect wallet' with no content.
- —No request or response schema is available; integration requires trial and error.
- —The 'ach' path segment may imply financial/payment processing, which could be a regulated category.
Citations
- —The endpoint returns a valid x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/ach/178
- —Platform pricing is $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base networkhttps://lowpaymentfee.com/api/v1/ach/178