x402-gated transaction receipt endpoint on Base, paid per-call in USDC.
What it does
This endpoint at lowpaymentfee.com provides access to a specific transaction receipt (transaction ID 353) behind an x402 paywall. The broader lowpaymentfee.com platform advertises a suite of pay-per-request APIs spanning data & analytics, AI & machine learning (sentiment analysis, summarization, classification, embeddings), finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and infrastructure utilities (geocoding, validation, conversion, generation). All endpoints are priced at $0.02 per request, settled in USDC on the Base network, with no API keys, no rate limits, and no commitments required.
The specific endpoint probed (/api/v1/transactions/353/receipt) returned a valid x402 challenge with a maxAmountRequired of 20,000 base units of USDC (0x8335… on Base). Since USDC uses 6 decimals, this translates to $0.02 per call, consistent with the site's advertised pricing. The payment scheme is "exact" with a 300-second timeout. The endpoint accepts POST requests and returns application/json.
Documentation is extremely sparse — the /docs, /api, /pricing, and /README pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI spec, no request/response schema documentation, and no examples of what the receipt payload actually contains. The platform appears to be a demonstration or early-stage x402 showcase rather than a mature API provider.
Capabilities
Use cases
- —Retrieving a transaction receipt for transaction 353 via a single USDC micropayment
- —Demonstrating x402 protocol payment flows on Base network
- —Integrating pay-per-request APIs without API key management
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents that can settle USDC payments on Base for per-call API access
- —Projects needing keyless, pay-as-you-go API consumption
Not for
- —Production workloads requiring documented request/response schemas
- —Users who need free or subscription-based API access
- —Applications requiring high-throughput with predictable billing
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/353/receipt \
-H "X-PAYMENT: <x402-payment-token>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing ($0.02 USDC on Base). However, there is no OpenAPI spec, no documentation beyond a landing page listing, no request/response schema, and no examples. The specific endpoint appears to be for a single transaction receipt (ID 353) with unclear utility. Docs pages are empty.
Warnings
- —No OpenAPI or schema documentation available — request and response formats are unknown
- —All documentation pages (/docs, /api, /pricing, /README) render only 'Connect wallet' with no content
- —This endpoint is for a specific transaction ID (353); unclear if it generalizes or is a demo artifact
- —The platform may be an early-stage demonstration rather than a production service
Citations
- —All endpoints priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —Platform offers APIs across data & analytics, AI & ML, finance & Web3, and infrastructure categorieshttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/transactions/353/receipt