Transaction receipt retrieval via x402 micropayment on Base network, $0.02 per request in USDC.
What it does
This endpoint at lowpaymentfee.com provides access to a transaction receipt (transaction ID 388) behind an x402 paywall. The site operates a broad suite 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. No API keys, rate limits, or upfront commitments are required — callers simply attach an x402 payment header to each request.
The specific endpoint `/api/v1/transactions/388/receipt` is labeled "Premium API Access" and accepts POST requests. The x402 challenge confirms it is live, requiring a maximum of 20,000 base units of USDC (0.02 USD, since USDC uses 6 decimals) paid to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` on Base. The response MIME type is `application/json`. The payment timeout is 300 seconds.
Documentation beyond the landing page is extremely thin — the /docs, /api, /pricing, and /README pages all render only a "Connect wallet" prompt with no additional technical detail. There is no OpenAPI spec, no request/response schema documentation, and no example payloads available. The exact structure of the receipt response and what input parameters (if any) the POST body accepts are unknown. The broader site lists many other endpoints (analytics, AI, finance, utilities) at the same $0.02 price point, but none have documented schemas either.
Capabilities
Use cases
- —Retrieving a receipt for a specific transaction (ID 388) via programmatic API call
- —Demonstrating x402 protocol micropayment integration on Base
- —Agent-driven receipt fetching without API key provisioning
Fit
Best for
- —Developers experimenting with x402 payment protocol on Base
- —Agents that need to fetch transaction receipts with instant crypto micropayments
- —Use cases where no-signup, pay-per-call access is preferred
Not for
- —Bulk retrieval of many different transaction receipts (only transaction 388 is exposed at this endpoint)
- —Users who need detailed API documentation or request/response schemas before integrating
- —Non-crypto payment workflows — this endpoint only accepts USDC on Base
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/388/receipt \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is confirmed live via a valid x402 402 challenge with clear pricing and network details. However, there is no OpenAPI spec, no documented request/response schema, no examples, and the docs pages are empty beyond a wallet-connect prompt. The specific purpose of this receipt endpoint is unclear beyond its label.
Warnings
- —No OpenAPI or schema documentation available — request body and response structure are unknown
- —All documentation pages (/docs, /api, /pricing, /README) render only 'Connect wallet' with no content
- —This endpoint is for a single hardcoded transaction ID (388); unclear if other transaction IDs are available at similar paths
- —The broader site lists many endpoints but none have published schemas or usage examples
Citations
- —The endpoint returns a 402 x402 challenge requiring 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/transactions/388/receipt
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/transactions/388/receipt
- —All APIs priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —Site lists endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com