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 253) 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/253/receipt) is live and returns a valid x402 challenge. It accepts POST requests and requires payment of up to 20,000 base units of USDC (0x8335…2913 on Base). Since USDC uses 6 decimals, this translates to $0.02 per call, consistent with the platform's advertised pricing. Payment is made via the x402 "exact" scheme, with a 300-second timeout window.
Documentation on the site is extremely thin — the docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no substantive content. There is no OpenAPI spec, no request/response examples, and no detailed documentation for any endpoint. The platform appears to be a demonstration or early-stage deployment of x402-based micropayment APIs rather than a mature, well-documented service.
Capabilities
Use cases
- —Retrieving a transaction receipt for transaction 253 via a single micropayment
- —Demonstrating x402 protocol-based pay-per-request API access
- —Programmatic access to paid API endpoints without API key management
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents that can settle USDC micropayments on Base
- —Use cases requiring keyless, pay-as-you-go API access
Not for
- —Production workloads requiring detailed API documentation and SLAs
- —Users who need free or subscription-based access without crypto wallets
- —Bulk data retrieval where per-request micropayments are impractical
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/253/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, but there is no OpenAPI spec, no request/response examples, and all documentation pages are empty stubs. The specific endpoint (transaction 253 receipt) is narrow in scope and its actual response format is unknown.
Warnings
- —All documentation pages (docs, API, pricing, README) render only 'Connect wallet' with no content
- —No OpenAPI or schema documentation available for any endpoint
- —This endpoint is scoped to a single transaction ID (253); unclear if it generalizes
- —The broader platform lists many endpoints but none have documented request/response schemas
- —Early-stage or demonstration deployment — reliability and longevity are uncertain
Citations
- —Platform advertises $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/transactions/253/receipt
- —Platform lists endpoints for analytics, AI/ML, finance/Web3, and infrastructure utilitieshttps://lowpaymentfee.com
- —Docs, API, pricing, and README pages contain only 'Connect wallet' prompthttps://lowpaymentfee.com/docs