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 63) behind an x402 paywall. It is part of a broader platform that offers a variety of pay-per-call APIs spanning 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 `/api/v1/transactions/63/receipt` accepts POST requests and returns an `application/json` response. Payment is handled via the x402 protocol: callers must include an `X-PAYMENT` header with a valid payment proof. The challenge advertises a maxAmountRequired of 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. The payment is sent to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` with a 300-second timeout.
The platform advertises no API keys, no rate limits, and instant access. Documentation pages (/docs, /pricing, /api, /README) all resolve but only show a "Connect wallet" prompt, so detailed API documentation is not publicly available. The actual content and schema of the receipt response are unknown — the endpoint is live (returns 402 as expected) but there is no OpenAPI spec or response examples to confirm what data the receipt contains.
Capabilities
Use cases
- —Retrieving a transaction receipt for transaction 63 via a micropayment
- —Demonstrating x402 protocol integration for pay-per-call APIs
- —Programmatic access to receipt data without API key management
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents that can settle USDC payments on Base
- —Use cases requiring keyless, pay-per-call API access
Not for
- —Users needing detailed API documentation or response schemas before integrating
- —High-volume batch retrieval where per-call pricing is impractical
- —Users without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/63/receipt \
-H "X-PAYMENT: <x402-payment-proof>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, confirming pricing and payment details. However, there is no OpenAPI spec, no response schema, no example responses, and all documentation pages only show 'Connect wallet' with no actual content. The specific purpose of this receipt endpoint (transaction 63) is unclear, and the broader platform's API catalog lacks any detailed documentation.
Warnings
- —No OpenAPI or response schema available — the actual receipt payload structure is unknown.
- —All documentation pages (/docs, /pricing, /api, /README) render only a 'Connect wallet' prompt with no usable content.
- —This endpoint references a specific transaction ID (63); it is unclear whether this is a demo or a production resource.
- —The broader platform advertises many API categories (AI, analytics, finance, utilities) but none have documented schemas or verifiable functionality.
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/transactions/63/receipt
- —The platform advertises $0.02 per request pricing across all APIs with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/transactions/63/receipt
- —Documentation pages resolve but only show 'Connect wallet'https://lowpaymentfee.com/docs