Transaction receipt endpoint on Base, paid per-call via x402 with USDC.
What it does
This endpoint at lowpaymentfee.com provides a transaction receipt resource at `/api/v1/transactions/11/receipt`. It is part of a broader platform that offers a variety of pay-per-request APIs spanning data analytics, AI/ML inference, finance/Web3 data, and infrastructure utilities — all gated via the x402 payment protocol on the Base network.
The specific endpoint probed returns a 402 challenge requesting payment in USDC (contract `0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913` on Base). The `maxAmountRequired` is 20,000 base units, which at 6 decimals for USDC equals $0.02 per request. Payment is made via the `exact` scheme to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3`, with a timeout of 300 seconds. The endpoint accepts POST requests and returns `application/json`.
The platform advertises a uniform $0.02/request pricing model across all its endpoints, with no API keys, no rate limits, and no minimum commitments. However, 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 schema, no request/response examples, and no description of what the "transaction receipt" resource actually contains or what input parameters it expects. The endpoint path suggests it retrieves a receipt for transaction ID 11, but the semantics are unclear.
Capabilities
Use cases
- —Retrieving a transaction receipt via a paid API call on Base
- —Demonstrating x402 payment protocol integration for per-request billing
- —Accessing pay-per-use infrastructure without API key management
Fit
Best for
- —Developers experimenting with x402 payment-gated APIs
- —Agents that can settle USDC payments on Base for per-call access
- —Projects needing keyless, pay-as-you-go API access
Not for
- —Production use cases requiring documented request/response schemas
- —Users who need free or subscription-based API access
- —Anyone needing detailed API documentation before integration
Quick start
# The endpoint requires an x402 USDC payment on Base.
# 1. POST to the endpoint, receive a 402 challenge.
# 2. Construct and sign a USDC payment of $0.02 (20000 base units).
# 3. Resubmit with X-PAYMENT header.
curl -X POST https://lowpaymentfee.com/api/v1/transactions/11/receipt
# Returns 402 with x402 challenge; pay and retry with payment header.Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge with clear pricing. However, there is no documentation, no OpenAPI schema, no request/response examples, and no explanation of what the transaction receipt resource contains or what inputs it expects. The docs/pricing/API pages are all blank beyond a wallet connect prompt.
Warnings
- —No API documentation available — docs, pricing, and API pages render only 'Connect wallet'
- —No OpenAPI or JSON schema describing request parameters or response format
- —The specific resource '/api/v1/transactions/11/receipt' has unclear semantics — it is unknown what data it returns
- —The broader platform lists many endpoints but none have documented schemas or examples
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units in USDC on Basehttps://lowpaymentfee.com/api/v1/transactions/11/receipt
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/transactions/11/receipt
- —Platform advertises $0.02/request uniform pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —Docs, API, pricing, and README pages render only 'Connect wallet' with no substantive contenthttps://lowpaymentfee.com/docs