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 363) 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/363/receipt) returns a valid x402 challenge with a maxAmountRequired of 20,000 base units of USDC (0x8335…2913 on Base). Since USDC uses 6 decimals, this equals $0.02 per call, consistent with the site's advertised pricing. Payment is made via the x402 "exact" scheme, requiring no API keys, no rate limits, and no prior registration — just an X-PAYMENT header with a valid payment proof.
Documentation is extremely thin. The /docs, /api, /pricing, and /README pages all render only a "Connect wallet" prompt with no substantive content. There is no OpenAPI spec, no request/response schema documentation, and no examples of what the receipt payload actually contains. The endpoint is live and responds correctly with a 402 challenge, but without documentation it is unclear what fields the receipt response includes or what request body (if any) is expected.
Capabilities
Use cases
- —Retrieving a transaction receipt for transaction 363 via a single micropayment
- —Programmatic access to paid API endpoints without API key management
- —Agent-driven workflows that need on-demand receipt data settled in USDC on Base
Fit
Best for
- —Developers or agents wanting keyless, pay-per-use API access
- —Crypto-native workflows that can sign x402 payment proofs on Base
- —Low-friction one-off data retrieval without subscription commitments
Not for
- —Users needing detailed API documentation or response schema guarantees before integrating
- —High-volume batch retrieval where per-call pricing may add up
- —Non-crypto users who cannot produce x402 payment headers
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/363/receipt
# Returns 402 with x402 challenge; attach X-PAYMENT header with valid USDC payment proof on Base to receive the receipt.Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing ($0.02 USDC on Base). However, there is no OpenAPI spec, no documentation of request or response schemas, and no examples. The docs pages are empty. The specific endpoint is for a single transaction receipt (ID 363), making its general utility unclear.
Warnings
- —No API documentation available — /docs, /api, /pricing, and /README pages all show only 'Connect wallet' with no content.
- —No OpenAPI or schema definition found for request or response payloads.
- —This endpoint is for a specific transaction ID (363); it is unclear whether other transaction IDs are available or how to discover them.
- —The broader platform advertises many API categories (AI, analytics, finance, utilities) but none could be verified beyond the landing page listings.
Citations
- —The endpoint returns a valid x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/transactions/363/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 & Machine Learning, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —USDC contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 with 6 decimalshttps://lowpaymentfee.com/api/v1/transactions/363/receipt