x402-gated transaction receipt endpoint on Base, paying $0.02 in USDC per request.
What it does
This endpoint at lowpaymentfee.com provides a transaction receipt resource (specifically for transaction ID 112) 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 call, settled in USDC on the Base network.
The specific endpoint `/api/v1/transactions/112/receipt` accepts POST requests and returns JSON. Payment is handled via the x402 protocol: callers must include an X-PAYMENT header with a valid payment proof. The challenge advertises a maxAmountRequired of 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. The payment is sent to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second timeout.
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 substantive content in the crawl. As a result, there is no detailed schema documentation, no example request/response payloads, and no clarity on what the receipt resource actually contains. The endpoint is confirmed live (402 challenge captured), but the lack of documentation limits confidence in what it returns.
Capabilities
Use cases
- —Retrieving a transaction receipt for transaction 112 via a single micropayment
- —Demonstrating x402 protocol integration for pay-per-request APIs
- —Agent-driven access to financial transaction data without API key management
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents that need keyless, pay-per-call API access on Base
- —Use cases requiring low-cost ($0.02) per-request billing in USDC
Not for
- —Users needing detailed API documentation or schema definitions before integrating
- —Bulk retrieval of many different transaction receipts (only transaction 112 is exposed at this path)
- —Users without USDC on Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/112/receipt \
-H "X-PAYMENT: <x402-payment-proof>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is confirmed live with a valid x402 402 challenge, but documentation pages are empty (wallet-gated). There is no OpenAPI spec, no request/response schema, and no examples. The purpose of the receipt resource is unclear beyond its name. Effectively a stub listing.
Warnings
- —All documentation pages (/docs, /pricing, /api, /README) returned only 'Connect wallet' with no substantive content
- —No OpenAPI or schema documentation available
- —No example request or response payloads documented
- —The endpoint path is specific to transaction ID 112; unclear if other transaction IDs are supported
- —The broader platform lists many API categories but none were probed beyond this single endpoint
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/transactions/112/receipt
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/transactions/112/receipt
- —Platform pricing is $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —Platform offers APIs across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com