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 398) 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/398/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, with a 300-second timeout. No API keys or rate limits are required — access is granted purely through on-chain payment.
Documentation is extremely sparse. 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 platform's landing page lists many endpoints across multiple categories, but without documentation it is unclear what data each returns or what input parameters they accept.
Capabilities
Use cases
- —Retrieving a transaction receipt for transaction 398 via programmatic payment
- —Exploring x402 protocol-based pay-per-request API patterns
- —Agents needing on-chain-settled API access without API key management
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents that can settle USDC payments on Base
- —Use cases requiring keyless, pay-as-you-go API access
Not for
- —Users needing well-documented API contracts with clear request/response schemas
- —Production workloads requiring SLA guarantees or support
- —Users without USDC on Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/398/receipt
# Returns 402 with x402 challenge; attach X-PAYMENT header with valid USDC payment on Base to receive the receipt.Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing. However, documentation is essentially nonexistent — all doc pages show only 'Connect wallet'. There is no OpenAPI spec, no request/response schema, no examples, and no explanation of what the receipt payload contains. The endpoint path suggests a single hardcoded transaction ID (398), which limits general utility.
Warnings
- —No documentation available — all doc/pricing/README pages render only 'Connect wallet'
- —No OpenAPI or schema definition for request or response payloads
- —Endpoint appears to be for a single specific transaction (ID 398), not a general-purpose receipt API
- —Platform lists many endpoints on its landing page but none have documented schemas or examples
- —Cannot verify what data the receipt actually returns without making a paid request
Citations
- —The endpoint returns a valid x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/transactions/398/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 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/transactions/398/receipt