x402-gated transaction receipt endpoint on Base, paid per-call in USDC.
What it does
This endpoint at lowpaymentfee.com provides a transaction receipt resource (transaction ID 35) behind an x402 paywall. It is part of a broader platform that advertises multiple 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/35/receipt` accepts POST requests and returns `application/json`. Payment is handled via the x402 protocol: callers receive a 402 challenge containing the accepted payment scheme (exact), the USDC asset contract on Base (`0x8335…`), and a maximum amount of 20,000 base units (i.e., $0.02 given USDC's 6 decimals). No API keys or rate limits are advertised; access is granted immediately upon valid payment.
Documentation is extremely sparse — the docs, pricing, API, and README pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI spec, no request/response schema beyond the x402 challenge's `outputSchema` stub, and no explanation of what the receipt payload actually contains. The platform appears to be a demonstration or early-stage x402 showcase rather than a mature production API.
Capabilities
Use cases
- —Retrieving a transaction receipt for transaction ID 35 via a paid API call
- —Demonstrating x402 protocol payment flows on Base
- —Integrating per-call USDC micropayments into agent workflows
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents that need to make one-off paid API calls without API keys
- —Testing USDC micropayment integrations on Base
Not for
- —Production workloads requiring documented request/response schemas
- —Bulk or high-volume data retrieval with predictable SLAs
- —Users who need fiat or non-crypto payment options
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/35/receipt
# Returns 402 with x402 challenge; attach X-PAYMENT header with valid USDC payment to receive the receipt.Endpoint
Quality
The endpoint is live (402 challenge captured) and pricing is clear ($0.02 USDC on Base), but there is no documentation, no OpenAPI spec, no request/response examples, and the docs pages are empty stubs. The purpose and content of the receipt resource is unexplained, making this effectively a stub listing.
Warnings
- —Documentation pages (/docs, /pricing, /api, /README) all render only 'Connect wallet' with no usable content.
- —No OpenAPI or schema describing request parameters or response format.
- —The specific resource (transaction 35 receipt) is opaque — no explanation of what it returns.
- —Platform may be a demo or early-stage project; production readiness is unclear.
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units in USDC on Base networkhttps://lowpaymentfee.com/api/v1/transactions/35/receipt
- —The platform advertises $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/transactions/35/receipt
- —Docs, pricing, API, and README pages render only 'Connect wallet'https://lowpaymentfee.com/docs