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 395) 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 (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 minimum commitments.
The specific endpoint probed (/api/v1/transactions/395/receipt) returns a valid x402 challenge (HTTP 402) requesting payment of up to 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 to the specified payTo address, with a 300-second timeout. The endpoint accepts POST requests and returns application/json.
Documentation is extremely sparse — the /docs, /api, /pricing, 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 appears to be a demonstration or early-stage deployment of x402-based micropayment APIs rather than a mature production service.
Capabilities
Use cases
- —Retrieving a transaction receipt for transaction 395 via micropayment
- —Demonstrating x402 protocol-based API monetization
- —Agent-driven pay-per-call data retrieval without API key management
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents that need keyless, pay-per-call API access on Base
- —Testing micropayment-gated API workflows
Not for
- —Production workloads requiring documented request/response schemas
- —Users needing bulk or subscription-based access at lower per-call cost
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/395/receipt
# Returns 402 with x402 challenge; include X-PAYMENT header with signed USDC payment to complete the request.Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing, but there is no documentation, no OpenAPI spec, no request/response schema, and no examples of what the receipt payload contains. The docs pages are empty. This is effectively a stub listing.
Warnings
- —No OpenAPI or schema documentation available — all docs pages render only 'Connect wallet'
- —No request body schema or response schema documented; unclear what the receipt contains
- —This appears to be a single transaction-specific endpoint (transaction 395) rather than a general-purpose API
- —Platform may be a demo or early-stage deployment; maturity is uncertain
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 requests maxAmountRequired of 20000 base units of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/transactions/395/receipt
- —Platform offers APIs across data & analytics, AI/ML, finance & Web3, and infrastructure categorieshttps://lowpaymentfee.com