x402-gated transaction receipt endpoint on Base, paying $0.02 in USDC per call.
What it does
This endpoint at lowpaymentfee.com provides a transaction receipt resource behind an x402 paywall. It is part of a broader platform that offers a variety of pay-per-request APIs spanning data analytics, AI/ML inference, finance/Web3 data, and infrastructure utilities — all priced at $0.02 per request and settled in USDC on the Base network.
The specific endpoint `/api/v1/transactions/8/receipt` returns a JSON response (MIME type `application/json`) when a valid x402 payment header is supplied. The x402 challenge advertises a max amount of 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. Payment is sent to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` using the "exact" scheme. The endpoint accepts POST requests and is marked as discoverable.
The platform advertises no API keys, no rate limits, and instant access. Documentation pages (`/docs`, `/pricing`, `/api`, `/README`) all appear to require a wallet connection and contain no additional content beyond that prompt, so details about request/response schemas, available parameters, or the exact structure of the receipt payload are unknown.
Capabilities
Use cases
- —Retrieving a transaction receipt for a specific transaction ID via programmatic payment
- —Demonstrating x402 protocol integration for pay-per-request APIs
- —Building agent workflows that need on-chain proof-of-payment receipts
Fit
Best for
- —Developers experimenting with x402 payment protocol on Base
- —Agents needing low-cost, keyless API access settled in USDC
- —Applications requiring transaction receipt data without subscription commitments
Not for
- —Users who need detailed API documentation or schema definitions before integrating
- —High-throughput batch processing where per-request crypto settlement adds latency
- —Users without a Base-network USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/8/receipt \
-H "X-PAYMENT: <x402-payment-header>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing. However, there is no OpenAPI schema, no documentation beyond a wallet-connect prompt, no example request/response payloads, and the specific purpose of the 'transactions/8/receipt' resource is unclear. This is effectively a stub listing.
Warnings
- —Documentation pages (/docs, /pricing, /api, /README) all render only a 'Connect wallet' prompt with no usable content.
- —No request or response schema is available — the payload structure of the receipt is unknown.
- —The endpoint path includes a hardcoded transaction ID ('8'), suggesting it may be a demo or placeholder rather than a general-purpose API.
- —The broader platform lists many API categories (AI, analytics, finance, utilities) but none could be verified beyond the landing page descriptions.
Citations
- —The x402 challenge advertises maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/transactions/8/receipt
- —USDC contract address on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/transactions/8/receipt
- —Platform advertises $0.02 per request, no API keys, no rate limits, instant accesshttps://lowpaymentfee.com
- —Platform lists APIs across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com