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 (transaction ID 41) behind an x402 paywall. It is part of a broader platform that offers a variety of pay-per-request APIs spanning data analytics, AI/ML inference, finance/Web3 data, and infrastructure utilities — all priced at $0.02 per call, settled in USDC on the Base network.
The specific endpoint `/api/v1/transactions/41/receipt` accepts POST requests and returns `application/json`. Payment is handled via the x402 protocol: callers must include an `X-PAYMENT` header with a valid payment proof. The x402 challenge advertises a maxAmountRequired of 20,000 base units of USDC (contract `0x8335…2913` on Base), which equals $0.02 given USDC's 6 decimals. The payment is sent to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` with a timeout of 300 seconds.
Documentation on the site is extremely thin — 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 example payloads available. The platform advertises no API keys, no rate limits, and instant access, but the actual behavior and response format of this specific receipt endpoint cannot be confirmed from available materials.
Capabilities
Use cases
- —Retrieving a transaction receipt for transaction 41 via a micropayment-gated API
- —Demonstrating x402 protocol integration for pay-per-request services
- —Programmatic access to receipt data without API key management
Fit
Best for
- —Developers experimenting with x402 protocol payments
- —Agents that can settle USDC on Base for per-call API access
- —Use cases needing keyless, pay-as-you-go API access
Not for
- —Users needing detailed API documentation or response schemas before integrating
- —High-volume batch retrieval where per-request pricing is inefficient
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/41/receipt \
-H "X-PAYMENT: <x402-payment-proof>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing, but there is zero documentation on request parameters, response schema, or what the receipt actually contains. Docs pages are empty. The specific endpoint path (transactions/41/receipt) suggests a single hardcoded resource rather than a general-purpose API.
Warnings
- —No OpenAPI spec or schema documentation available
- —All documentation pages (docs, API, pricing, README) render only 'Connect wallet' with no content
- —The endpoint path references a specific transaction ID (41); unclear if this is parameterizable or a fixed demo resource
- —Response format and fields are completely undocumented
- —The broader platform lists many endpoints but none have documented schemas
Citations
- —The x402 challenge advertises maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/transactions/41/receipt
- —All APIs on the platform are priced at $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/transactions/41/receipt
- —Payment is sent to 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3https://lowpaymentfee.com/api/v1/transactions/41/receipt