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 (specifically for transaction ID 44) behind an x402 paywall. The site advertises itself as a platform hosting multiple pay-per-request API categories including Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure utilities — all priced at $0.02 per request, settled in USDC on the Base network.
The specific endpoint `/api/v1/transactions/44/receipt` returns a JSON response upon payment. The x402 challenge confirms the endpoint is live, accepting POST requests with an exact-payment scheme. The max amount required is 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. Payment is sent to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second timeout.
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 schema, no request/response examples, and no description of what the receipt payload actually contains. The site's landing page lists many other endpoints across analytics, AI, finance, and utility categories, but none have documented schemas either. The endpoint is functional (returns a proper 402 challenge), but the lack of documentation makes it difficult to know what data is returned.
Capabilities
Use cases
- —Retrieving a transaction receipt for transaction 44 via micropayment
- —Demonstrating x402 protocol payment flows on Base
- —Agent-driven pay-per-request data retrieval without API keys
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents needing keyless, pay-per-call API access on Base
- —Testing USDC micropayment integrations
Not for
- —Production workloads requiring documented response schemas
- —Bulk transaction receipt retrieval across many transaction IDs
- —Users without USDC on Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/44/receipt
# Returns 402 with x402 challenge; attach X-PAYMENT header with valid USDC payment to receive the receipt.Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, but documentation is essentially nonexistent — docs/pricing/API pages all show only 'Connect wallet'. There is no OpenAPI schema, no example request or response, and no description of what the receipt contains. The endpoint path is hardcoded to transaction ID 44 with no explanation of what that represents.
Warnings
- —No documentation available — docs, pricing, API, and README pages all render only 'Connect wallet'
- —No OpenAPI or response schema provided; unknown what the receipt payload contains
- —Endpoint is hardcoded to transaction ID 44 with no context on what this transaction represents
- —Site lists many other endpoints but none appear documented either
- —Cannot verify the actual utility or data quality of the response without paying
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/transactions/44/receipt
- —All APIs on the site are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/transactions/44/receipt