x402-gated transaction receipt endpoint on Base, paid per-call in USDC.
What it does
This endpoint at lowpaymentfee.com provides a transaction receipt resource (transaction ID 31) behind an x402 paywall. It is part of a broader platform that advertises multiple API categories including data & analytics, AI & machine learning, finance & Web3, and infrastructure utilities — all priced at $0.02 per request and settled in USDC on the Base network.
The specific endpoint `/api/v1/transactions/31/receipt` accepts POST requests and returns `application/json`. Payment is handled via the x402 protocol: callers receive a 402 challenge containing the accepted payment scheme (exact), the USDC asset contract on Base (`0x8335…`), and a maximum amount of 20,000 base units (i.e., $0.02 given USDC's 6 decimals). No API keys or rate limits are advertised; access is granted purely through per-request micropayments.
Documentation on the site is extremely thin — the docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no further technical detail. There is no OpenAPI spec, no request/response schema beyond the x402 outputSchema stub, and no examples of what the receipt payload actually contains. The endpoint is confirmed live (402 challenge captured), but the lack of documentation makes it difficult to know what data the receipt returns or what inputs the POST body expects.
Capabilities
Use cases
- —Retrieving a transaction receipt for transaction 31 via a single micropayment
- —Demonstrating x402 protocol integration for pay-per-call APIs
- —Programmatic access to receipt data without API key management
Fit
Best for
- —Developers experimenting with x402 payment flows
- —Agents that can settle USDC micropayments on Base
- —Use cases needing keyless, pay-as-you-go API access
Not for
- —Users who need detailed API documentation or request/response schemas before integrating
- —High-volume batch retrieval where per-call fees add up
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/31/receipt
# Returns 402 with x402 challenge; include X-PAYMENT header with signed USDC payment to access the receipt.Endpoint
Quality
The endpoint is confirmed live via a valid 402 challenge, but documentation is essentially nonexistent — every doc page returns only 'Connect wallet'. There is no OpenAPI spec, no request/response schema, and no explanation of what the receipt contains or what POST body is expected. The listing is effectively a stub.
Warnings
- —Documentation pages (/docs, /api, /pricing, /README) all render only 'Connect wallet' with no usable content.
- —No OpenAPI or request/response schema available; the actual receipt payload structure is unknown.
- —The endpoint is for a specific transaction ID (31); it is unclear whether this is a demo or a production resource.
- —The broader platform advertises many API categories (AI, analytics, finance, utilities) but no evidence these endpoints return real data.
Citations
- —The endpoint returns a 402 challenge with x402Version 1, accepting USDC on Base with maxAmountRequired 20000 (i.e., $0.02).https://lowpaymentfee.com/api/v1/transactions/31/receipt
- —The platform advertises $0.02 per request pricing with no API keys, no rate limits, and instant access on the Base network.https://lowpaymentfee.com
- —The USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913.https://lowpaymentfee.com/api/v1/transactions/31/receipt
- —Documentation, API, pricing, and README pages render only a 'Connect wallet' prompt.https://lowpaymentfee.com/docs