x402-gated transaction receipt endpoint on Base, paying $0.02 in USDC per request.
What it does
This endpoint at lowpaymentfee.com provides a transaction receipt resource behind an x402 paywall. The specific path `/api/v1/transactions/28/receipt` returns a JSON receipt for transaction #28 when the caller supplies a valid X-PAYMENT header with USDC on the Base network. The cost is 20,000 base units of USDC (6 decimals), which equals $0.02 per request.
The broader lowpaymentfee.com platform advertises a suite of x402-gated APIs spanning data & analytics (metrics, reports, data export, insights), AI & machine learning (sentiment analysis, text summarization, classification, embeddings), finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and infrastructure utilities (geocoding, validation, conversion, generation). All endpoints are listed at $0.02 per request with no API keys, no rate limits, and no commitments required — payment is handled entirely via the x402 protocol on the Base L2 network using USDC.
Documentation is extremely sparse: the /docs, /pricing, /api, and /README pages all render only a "Connect wallet" prompt with no further technical detail. There is no OpenAPI spec, no request/response schema documentation, and no usage examples available from the crawled content. The endpoint is confirmed live (returns a proper 402 challenge), but the actual response payload structure is unknown.
Capabilities
Use cases
- —Retrieving a transaction receipt for transaction #28 via programmatic x402 payment
- —Demonstrating x402 protocol integration with USDC on Base
- —Agent-driven pay-per-call access to financial transaction data
Fit
Best for
- —Developers experimenting with x402 protocol payments
- —Agents that need pay-per-call access without API key management
- —Low-cost micro-transaction receipt retrieval on Base
Not for
- —Production workloads requiring documented request/response schemas
- —Bulk transaction receipt retrieval (single fixed transaction ID in path)
- —Users who need fiat-only payment rails
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/28/receipt \
-H "X-PAYMENT: <x402-payment-header>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, confirming it works. However, documentation is essentially nonexistent — all doc pages show only 'Connect wallet'. There is no OpenAPI spec, no request/response schema, no examples, and the specific endpoint path (/transactions/28/receipt) is hardcoded to a single transaction ID with no explanation of what it returns. The broader platform lists many endpoints but none are documented beyond a name and price.
Warnings
- —No documentation available — /docs, /pricing, /api, and /README all render only 'Connect wallet'
- —No OpenAPI or schema definition found for any endpoint
- —The specific endpoint path is hardcoded to transaction ID 28; unclear if other IDs are available or what the receipt contains
- —Response payload structure is completely unknown
- —The platform lists many API categories (AI, analytics, finance, utilities) but none have documented schemas or examples
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/transactions/28/receipt
- —All endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The platform lists APIs across Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —USDC asset address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/transactions/28/receipt