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 194) behind an x402 paywall. The broader lowpaymentfee.com platform advertises a suite of pay-per-request 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 minimum commitments.
The specific endpoint probed (/api/v1/transactions/194/receipt) returned a valid x402 challenge with a maxAmountRequired of 20,000 base units of USDC (0x8335… on Base, 6 decimals), which equals $0.02. Payment is made via the x402 "exact" scheme to the specified payTo address. The endpoint accepts POST requests and returns application/json. Documentation pages (/docs, /pricing, /api, /README) all rendered only a "Connect wallet" prompt with no further content, so detailed request/response schemas are unavailable.
Because the crawled documentation is essentially empty beyond the landing page listing and the x402 challenge metadata, the actual structure of the receipt response and any required POST body fields remain unknown. The platform appears to be a demonstration or early-stage x402 marketplace rather than a mature production API.
Capabilities
Use cases
- —Retrieving a transaction receipt for transaction 194 via a single micropayment
- —Demonstrating x402 protocol payment flows on Base
- —Agent-driven pay-per-request 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 endpoint integrations
Not for
- —Production workloads requiring documented request/response schemas
- —Bulk or high-volume data retrieval where per-request pricing is inefficient
- —Users who need fiat-only payment rails
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/194/receipt
# Returns 402 with x402 challenge; include X-PAYMENT header with signed USDC payment to proceed.Endpoint
Quality
The x402 challenge is live and well-formed, confirming the endpoint exists and its price ($0.02 USDC on Base). However, documentation pages are empty stubs, there is no OpenAPI spec, no request/response schema, and the endpoint path suggests a single fixed resource (transaction 194) rather than a general-purpose API. Very limited information to work with.
Warnings
- —All documentation pages (/docs, /pricing, /api, /README) return only a 'Connect wallet' prompt with no actual content.
- —No OpenAPI or request/response schema available; POST body requirements are unknown.
- —The endpoint path references a specific transaction ID (194), suggesting it may not be a general-purpose API.
- —Platform may be a demo or early-stage project; production readiness is unclear.
Citations
- —All listed endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base network.https://lowpaymentfee.com
- —The x402 challenge returns maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base, equaling $0.02.https://lowpaymentfee.com/api/v1/transactions/194/receipt
- —The platform offers APIs across data & analytics, AI & ML, finance & Web3, and infrastructure categories.https://lowpaymentfee.com