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 behind an x402 paywall. It is part of a broader platform that offers a variety of pay-per-request APIs spanning data & analytics, AI & machine learning, finance & Web3, and infrastructure utilities — all priced at $0.02 per call and settled in USDC on the Base network.
The specific endpoint `/api/v1/transactions/4/receipt` returns a JSON response (MIME type `application/json`) and accepts POST requests. Payment is handled via the x402 protocol: callers receive a 402 challenge containing the payment details (asset, amount, payTo address) and must include a valid `X-PAYMENT` header to proceed. The max amount required is 20,000 base units of USDC (6 decimals), which equals $0.02. No API keys, rate limits, or upfront commitments are required — access is instant once payment is included.
The platform advertises additional endpoints for metrics, reports, data export, insights, sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and generation. Documentation pages exist but appear to require a wallet connection to view, so detailed schemas and response examples are not available from the crawl.
Capabilities
Use cases
- —Retrieving transaction receipts programmatically with per-call USDC payment
- —Integrating pay-per-request APIs into agent workflows without API key management
- —Accessing financial or transactional data behind a crypto-native paywall
Fit
Best for
- —Agents or bots that need on-demand transaction receipts without subscription overhead
- —Developers experimenting with x402 protocol integrations on Base
- —Crypto-native applications that prefer per-call USDC settlement
Not for
- —High-volume batch processing where per-call pricing becomes expensive
- —Users without access to USDC on the Base network
- —Applications requiring detailed OpenAPI documentation or guaranteed SLAs
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/4/receipt
# Returns 402 with x402 challenge. Include X-PAYMENT header with valid payment proof to receive the receipt.Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing. However, there is no OpenAPI schema, no response examples, and the docs/pricing/README pages all render only a 'Connect wallet' prompt with no usable content. The specific purpose of 'transactions/4/receipt' is unclear — it may be a demo or placeholder. Very little can be verified beyond the 402 challenge itself.
Warnings
- —Documentation, pricing, and README pages require wallet connection and provide no readable content from crawl.
- —The endpoint path '/api/v1/transactions/4/receipt' references a hardcoded transaction ID (4), suggesting it may be a demo or example rather than a general-purpose endpoint.
- —No OpenAPI spec, no response schema, and no example responses are available.
- —The broader platform lists many endpoints (AI, finance, utils) but none could be verified beyond the landing page descriptions.
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/transactions/4/receipt
- —All APIs are priced at $0.02 per request with no API keys, no rate limits, and instant access on the Base networkhttps://lowpaymentfee.com
- —The platform offers endpoints across Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —USDC asset address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/transactions/4/receipt