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 265) 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/265/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 translates to $0.02 per call, consistent with the site's advertised pricing. Payment is made via the x402 "exact" scheme to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3, with a 300-second timeout. No API keys or rate limits are required; access is granted immediately upon payment.
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 endpoint is live and responding with a proper 402 challenge, but the lack of documentation makes it difficult to know what data is returned or what input parameters (if any) the POST body expects.
Capabilities
Use cases
- —Retrieving transaction receipt data for transaction ID 265 via a single paid API call
- —Programmatic access to receipt information without pre-registration or API keys
- —Agent-driven workflows that need to fetch financial transaction records on-demand
Fit
Best for
- —Agents or applications that can settle USDC payments on Base via x402
- —Use cases requiring keyless, pay-as-you-go API access
- —Developers exploring x402 protocol integrations
Not for
- —Users who need detailed API documentation or response schema guarantees before integrating
- —High-volume batch retrieval where per-call pricing may add up
- —Users without access to USDC on the Base network
Quick start
# 1. Send POST to get the 402 challenge
curl -X POST https://lowpaymentfee.com/api/v1/transactions/265/receipt
# Returns 402 with x402 payment challenge
# 2. Construct X-PAYMENT header with USDC payment proof on Base
# 3. Resend POST with X-PAYMENT header to receive the receiptEndpoint
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 parameters or response schema, and the docs/pricing/README pages are all empty beyond a wallet connect prompt. The specific purpose of this transaction receipt endpoint is unclear.
Warnings
- —No API documentation available — /docs, /api, /pricing, and /README pages all show only 'Connect wallet' with no content
- —No OpenAPI or JSON schema describing request body or response format
- —The endpoint is for a specific transaction ID (265); it is unclear whether this is a general-purpose receipt endpoint or a single fixed resource
- —The broader platform advertises many API categories (AI, analytics, finance, utilities) but no evidence of documentation or working examples for any of them
Citations
- —All endpoints priced at $0.02 per request with no API keys, no rate limits, on Base networkhttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/transactions/265/receipt
- —Platform advertises APIs for data analytics, AI/ML, finance/Web3, and infrastructure utilitieshttps://lowpaymentfee.com