Pay-per-call transaction receipt endpoint on Base via x402, priced at $0.02 in USDC.
What it does
This x402-enabled endpoint at lowpaymentfee.com provides a "Premium API Access" receipt for transaction ID 125. It is part of a broader platform offering multiple pay-per-request API categories including data & analytics, AI & machine learning, finance & Web3, and infrastructure utilities — all priced at $0.02 per request and settled in USDC on the Base network.
The specific endpoint `/api/v1/transactions/125/receipt` accepts POST requests and returns JSON. Payment is handled via the x402 protocol: callers must include an X-PAYMENT header with a valid payment proof. The challenge advertises a maxAmountRequired of 20000 base units of USDC (contract 0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. No API keys or rate limits are advertised; access is gated purely by micropayment.
Documentation on the site is extremely sparse — the /docs, /pricing, /api, and /README pages all render only a "Connect wallet" prompt with no substantive content. There is no OpenAPI spec, no request/response schema beyond the x402 outputSchema stub, and no explanation of what the receipt payload actually contains. The platform lists many other endpoints across analytics, AI, finance, and utility categories, but none have documented schemas either. Treat this as a low-documentation endpoint where the actual response structure is unknown until a paid request is made.
Capabilities
Use cases
- —Retrieving a transaction receipt for transaction 125 via a single micropayment
- —Demonstrating x402 protocol integration for pay-per-call APIs
- —Accessing paid API data without API key registration
Fit
Best for
- —Developers experimenting with x402 micropayment protocol
- —Agents that can settle USDC payments on Base automatically
- —Use cases requiring keyless, pay-as-you-go API access
Not for
- —Users needing well-documented API schemas and response contracts
- —Bulk or high-volume receipt retrieval (no batch endpoint documented)
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/125/receipt \
-H "X-PAYMENT: <x402-payment-proof>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is live (402 challenge captured) and pricing is clear ($0.02 USDC on Base), but there is no OpenAPI spec, no documented request/response schema, no examples, and all documentation pages return only a wallet-connect prompt. The specific purpose of this receipt endpoint is unclear beyond its URL path.
Warnings
- —No OpenAPI or schema documentation available — response structure is entirely unknown
- —All doc/pricing/README pages render only 'Connect wallet' with no content
- —The endpoint path references a hardcoded transaction ID (125); unclear if this is parameterized or fixed
- —No information on what data the receipt actually contains
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/transactions/125/receipt
- —All APIs are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The platform offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/transactions/125/receipt