x402-gated transaction receipt endpoint on Base, paid per-call in USDC.
What it does
This endpoint at lowpaymentfee.com provides access to a specific transaction receipt (transaction ID 248) behind an x402 paywall. The broader lowpaymentfee.com platform advertises a suite of pay-per-request APIs spanning data analytics, AI/ML inference (sentiment analysis, summarization, classification, embeddings), finance/Web3 data (price feeds, exchange rates, token quotes, gas estimates), and infrastructure utilities (geocoding, validation, conversion, generation). All endpoints are priced at $0.02 per request, settled in USDC on the Base network via the x402 protocol.
The specific endpoint probed (/api/v1/transactions/248/receipt) returned a valid x402 challenge with a maxAmountRequired of 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. Payment is made via the "exact" scheme to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3, with a 300-second timeout. The endpoint accepts POST requests and returns application/json.
Documentation is extremely sparse — the /docs, /pricing, /api, 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 examples of what the receipt payload actually contains. The platform's landing page lists many API paths but provides no detail on request parameters or response formats for any of them. This makes it difficult to assess what data is actually returned or how to construct valid requests beyond the payment header.
Capabilities
Use cases
- —Retrieving a transaction receipt for transaction 248 via a single paid API call
- —Programmatic access to paid data endpoints without API key registration
- —Agent-driven micropayment workflows using x402 on Base
Fit
Best for
- —Developers experimenting with x402 payment protocol integrations
- —Agents that can settle USDC payments on Base for per-call API access
- —Use cases requiring no-signup, no-rate-limit API access
Not for
- —Users needing detailed API documentation or schema definitions before integrating
- —Bulk or high-volume data retrieval where per-call pricing is inefficient
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/248/receipt
# Returns 402 with x402 challenge; attach X-PAYMENT header with valid USDC payment proof to receive the receipt.Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, but documentation is essentially nonexistent — no OpenAPI spec, no request/response schemas, no examples. The /docs and other pages render only a wallet-connect prompt. The specific purpose of this particular receipt endpoint (transaction 248) is unclear, and the broader platform's many advertised APIs lack any documented contracts.
Warnings
- —No OpenAPI specification or schema documentation available
- —All documentation pages (/docs, /pricing, /api, /README) render only 'Connect wallet' with no content
- —No request parameters or response format documented for any endpoint
- —The specific endpoint is for a single transaction ID (248) — unclear if this is a demo or a real resource
- —The platform lists many API categories (AI, finance, analytics, etc.) but provides zero detail on any of them
Citations
- —The endpoint returns a valid x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/transactions/248/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 advertises APIs across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —USDC contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 with 6 decimalshttps://lowpaymentfee.com/api/v1/transactions/248/receipt