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 314) 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/314/receipt` accepts POST requests and returns an `application/json` response. Payment is handled via the x402 protocol: callers must include an `X-PAYMENT` header containing a valid payment proof. The maximum amount required is 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. There are no API keys, no rate limits, and no subscription commitments — each call is independently paid.
The platform advertises additional endpoints across four categories (Data & Analytics, AI & Machine Learning, Finance & Web3, Infrastructure), all at the same $0.02 price point. However, documentation beyond the landing page is extremely thin — the docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no further technical detail. No OpenAPI spec, request/response schemas, or usage examples are provided for this or any other endpoint on the platform.
Capabilities
Use cases
- —Retrieving a transaction receipt for transaction 314 via a single paid API call
- —Demonstrating x402 payment flows in agent-to-agent commerce
- —Integrating pay-per-call receipt lookups into automated financial workflows
Fit
Best for
- —Developers experimenting with x402 protocol integrations
- —Agents needing on-demand transaction receipts without subscription overhead
- —Low-volume, pay-as-you-go API consumption on Base
Not for
- —High-volume receipt retrieval where per-call costs add up quickly
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —Accessing receipts for arbitrary transaction IDs (this endpoint is hardcoded to ID 314)
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/314/receipt \
-H "X-PAYMENT: <x402-payment-proof>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge with clear pricing. However, there is no OpenAPI spec, no request/response schema, no documentation beyond a landing page, and the endpoint is scoped to a single hardcoded transaction ID (314) with no explanation of what data it returns. The docs/pricing/README pages are all empty stubs.
Warnings
- —No OpenAPI specification or response schema available for any endpoint on this platform
- —Documentation pages (/docs, /api, /pricing, /README) all render only 'Connect wallet' with no technical content
- —Endpoint is hardcoded to transaction ID 314 — unclear if other transaction IDs are supported or what the receipt contains
- —The broader platform advertises many endpoints (AI, analytics, finance, utils) but none have documented schemas or examples
Citations
- —The endpoint returns a 402 challenge requiring 20,000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base networkhttps://lowpaymentfee.com/api/v1/transactions/314/receipt
- —All APIs on the platform are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The platform offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —Documentation, API, pricing, and README pages render only a 'Connect wallet' prompthttps://lowpaymentfee.com/docs