Transaction receipt endpoint on Base, paid per-call via x402 with USDC.
What it does
This endpoint at lowpaymentfee.com provides access to a transaction receipt (resource ID 173) behind an x402 paywall. The broader lowpaymentfee.com platform advertises a suite of APIs spanning data & analytics, AI & machine learning (sentiment analysis, summarization, classification, embeddings), finance & Web3 (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 with no API keys, no rate limits, and no commitments required.
The specific probed endpoint (`/api/v1/transactions/173/receipt`) returns 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 x402 "exact" scheme to the specified payTo address. The endpoint accepts POST requests and returns application/json. Documentation beyond the landing page is extremely sparse — the /docs, /api, /pricing, and /README pages all render only a "Connect wallet" prompt with no further technical detail, schemas, or example payloads.
Because there is no OpenAPI spec, no request/response schema documentation, and no examples of what the receipt payload actually contains, the practical utility of this specific endpoint is difficult to assess without making a paid call. The platform appears live and the x402 challenge is well-formed, but the lack of documentation is a significant gap.
Capabilities
Use cases
- —Retrieving a transaction receipt by paying $0.02 in USDC on Base
- —Demonstrating x402 protocol payment flows for agent-to-API commerce
- —Accessing paid API endpoints without traditional API key registration
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents that can settle USDC payments on Base L2
- —Use cases requiring keyless, pay-per-call API access
Not for
- —Users needing detailed API documentation or request/response schemas before purchasing
- —High-volume batch processing where per-call crypto settlement adds overhead
- —Users without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/173/receipt \
-H "X-PAYMENT: <x402-payment-token>" \
-H "Content-Type: application/json"Endpoint
Quality
The x402 challenge is live and well-formed, confirming the endpoint exists and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI spec, no request/response schema, no documentation beyond a landing page, and no examples of what the receipt payload contains. The /docs and other pages are empty. This is effectively a stub listing.
Warnings
- —No OpenAPI or schema documentation available — request and response formats are unknown
- —All documentation pages (/docs, /api, /pricing, /README) render only 'Connect wallet' with no content
- —The specific endpoint /api/v1/transactions/173/receipt appears to be for a single hardcoded resource ID (173); unclear if this generalizes
- —No examples of successful response payloads are available
Citations
- —All endpoints priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/transactions/173/receipt
- —Platform offers APIs across data & analytics, AI & ML, finance & Web3, and infrastructure categorieshttps://lowpaymentfee.com