x402-gated product inventory endpoint on Base, pay-per-request with USDC.
What it does
This endpoint at lowpaymentfee.com provides access to a product inventory resource (product ID 37) via the x402 payment protocol. It accepts POST requests and returns JSON. Payment is settled on the Base network using USDC (contract 0x8335…2913) with a maximum cost of 0.02 USDC per request (20,000 base units at 6 decimals).
The hosting site lowpaymentfee.com offers a broad catalog of x402-gated APIs spanning data & analytics, AI/ML inference, finance/Web3, and infrastructure utilities — all priced at $0.02 per request with no API keys, no rate limits, and no commitments. This specific endpoint falls under what appears to be a product/inventory domain, though the exact response schema and field definitions are not documented in the crawled material.
The endpoint is live and returns a valid x402 version-1 challenge when called without payment. No OpenAPI spec, detailed documentation, or example responses were found during the crawl — the docs, pricing, and README pages all rendered only a wallet-connect prompt with no substantive content. As a result, the actual data returned by this endpoint and its input parameters remain unclear.
Capabilities
Use cases
- —Querying product inventory data for product 37 on a per-request payment basis
- —Integrating pay-per-call inventory lookups into agent workflows without API key management
- —Demonstrating x402 protocol usage for micropayment-gated data access
Fit
Best for
- —Agents or services that need on-demand inventory data with no subscription commitment
- —Developers experimenting with x402 payment protocol integrations
- —Scenarios requiring keyless, pay-as-you-go API access on Base
Not for
- —High-volume inventory polling where per-request costs would accumulate quickly
- —Use cases requiring detailed API documentation or guaranteed SLAs
- —Users without access to USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/products/37/inventory \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, but there is no OpenAPI spec, no documentation beyond a wallet-connect stub, no example request/response, and no description of what the inventory data actually contains. The listing is essentially a stub with pricing and liveness confirmed.
Warnings
- —No OpenAPI or schema documentation available — input parameters and response format are unknown
- —Docs, pricing, and README pages render only a wallet-connect prompt with no substantive content
- —The purpose and contents of 'product 37 inventory' are not described anywhere in the crawled material
- —The site appears to host many endpoints but none have detailed documentation
Citations
- —Endpoint returns a valid x402 version-1 challenge with status 402https://lowpaymentfee.com/api/v1/products/37/inventory
- —Payment is in USDC on Base network with maxAmountRequired of 20000 base units (0.02 USDC)https://lowpaymentfee.com/api/v1/products/37/inventory
- —Site advertises $0.02 per request, no API keys, no rate limits, instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/products/37/inventory