Transaction receipt retrieval via x402 micropayment on Base network for $0.02 per request.
What it does
This endpoint at lowpaymentfee.com provides access to a transaction receipt (resource `/api/v1/transactions/331/receipt`) behind an x402 paywall. The provider operates a broader platform offering numerous pay-per-call API endpoints across categories including 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 probed returns a 402 challenge requesting payment of up to 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. Payment is made via the x402 "exact" scheme with a 300-second timeout. The endpoint accepts POST requests and returns `application/json`. No API keys or rate limits are advertised; access is gated purely by micropayment.
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 schema documentation, and no examples of what the receipt payload actually contains. The endpoint path suggests it retrieves a receipt for a specific transaction (ID 331), but it is unclear whether this is a demo/sample resource or a pattern for arbitrary transaction IDs.
Capabilities
Use cases
- —Retrieving transaction receipt data via a single micropayment
- —Demonstrating x402 protocol payment flows on Base
- —Agent-driven pay-per-call access to financial records
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents needing on-demand transaction receipts without API key management
- —Low-volume, pay-as-you-go API consumption on Base
Not for
- —High-volume batch retrieval where per-request fees add up
- —Users who need detailed API documentation or guaranteed SLAs
- —Non-crypto users who cannot pay in USDC on Base
Quick start
# 1. Send POST with x402 payment header to get the receipt
curl -X POST https://lowpaymentfee.com/api/v1/transactions/331/receipt \
-H "X-PAYMENT: <x402-payment-token>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge with clear pricing ($0.02 USDC on Base). However, there is no OpenAPI spec, no request/response schema, no documentation beyond a landing page listing, and no examples. The specific resource (transaction 331 receipt) is opaque — it's unclear what data is returned or whether the path is parameterized. Effectively a stub listing.
Warnings
- —No OpenAPI or schema documentation available — request and response formats are unknown
- —Docs, API, pricing, and README pages all render only 'Connect wallet' with no content
- —Unclear whether /transactions/331/receipt is a fixed demo resource or a parameterized pattern
- —No information on uptime, SLAs, or data freshness
Citations
- —Endpoint returns x402 402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/transactions/331/receipt
- —All APIs priced at $0.02 per request with no API keys, no rate limits, on Base networkhttps://lowpaymentfee.com
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/transactions/331/receipt