x402-gated transaction receipt endpoint on Base, paying $0.02 in USDC per request.
What it does
This endpoint at lowpaymentfee.com provides access to a transaction receipt (transaction ID 76) behind an x402 paywall. The broader lowpaymentfee.com platform advertises a suite of pay-per-call APIs spanning data analytics, AI/ML inference (sentiment analysis, summarization, classification, embeddings), finance/Web3 data (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 via the x402 protocol.
The specific probed endpoint (`/api/v1/transactions/76/receipt`) returns a valid x402 challenge (HTTP 402) requesting payment of 20,000 base units of USDC (0x8335…2913 on Base, 6 decimals = $0.02) to address 0x1A2B…85F3. The payment scheme is "exact" with a 300-second timeout. No API keys or rate limits are advertised — access is purely payment-gated.
Documentation is extremely sparse. 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 platform's landing page lists many endpoints across multiple categories, but without schemas or sample responses it is impossible to verify what data any of them actually return.
Capabilities
Use cases
- —Retrieving a transaction receipt for transaction 76 via a single micropayment
- —Demonstrating x402 payment-gated API access on Base
- —Agent-driven pay-per-call data retrieval without API key management
Fit
Best for
- —Developers experimenting with x402 payment protocol on Base
- —Agents that need keyless, pay-per-call API access
- —Use cases requiring USDC micropayments for individual API calls
Not for
- —Production workloads requiring documented request/response schemas
- —Bulk data retrieval where per-call pricing is inefficient
- —Users who need fiat-only payment options
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/76/receipt
# Returns HTTP 402 with x402 challenge.
# Include X-PAYMENT header with a valid x402 payment proof to receive the receipt.Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, but there is zero documentation on what the endpoint actually returns. No OpenAPI spec, no request/response examples, and all doc pages render only 'Connect wallet'. The specific endpoint path (/transactions/76/receipt) is not listed on the landing page, making its purpose unclear. Effectively a stub listing.
Warnings
- —No OpenAPI spec or schema documentation available
- —All documentation pages (docs, API, pricing, README) render only 'Connect wallet' with no content
- —The specific endpoint /api/v1/transactions/76/receipt is not listed among the advertised APIs on the landing page
- —No example request or response payloads are available to verify what data is returned
- —The endpoint appears to be for a single hardcoded transaction ID (76), which limits general utility
Citations
- —All endpoints priced at $0.02 per request with no API keys, no rate limits, on Base networkhttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/transactions/76/receipt
- —Platform advertises APIs across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —Documentation pages render only 'Connect wallet' with no substantive contenthttps://lowpaymentfee.com/docs