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 80) behind an x402 paywall. The endpoint accepts POST requests and returns JSON. Payment is settled on the Base network using USDC (contract 0x8335…2913) via the x402 "exact" scheme. The maximum amount required per call is 20,000 base units of USDC, which equals $0.02 given USDC's 6 decimals.
The hosting site lowpaymentfee.com advertises 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 minimum commitments. However, the specific endpoint listed here (/api/v1/products/80/inventory) is not among the APIs advertised on the landing page, and no documentation, request schema, or response schema is available for it. The docs, pricing, and README pages all resolve to a minimal "Connect wallet" stub with no further detail.
Because there is no OpenAPI spec, no request/response examples, and no documentation describing what "product 80 inventory" actually returns, the practical utility of this endpoint is unclear. The x402 challenge is live and well-formed, confirming the endpoint is operational, but callers have no way to know what payload to send or what data they will receive without experimentation.
Capabilities
Use cases
- —Querying inventory data for product ID 80 via a single paid POST request
- —Demonstrating x402 payment-gated API consumption on Base
- —Integrating pay-per-call inventory checks into agent workflows
Fit
Best for
- —Developers experimenting with x402 payment protocol on Base
- —Agents that can handle x402 challenges and USDC payments
- —Low-volume, on-demand inventory queries without API key management
Not for
- —Users who need documented request/response schemas before integrating
- —High-volume inventory systems requiring bulk or batch queries
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/products/80/inventory \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The x402 challenge is live and well-formed, confirming the endpoint works. However, there is no documentation, no request/response schema, no examples, and the specific endpoint is not listed on the provider's own landing page. This is effectively a stub listing.
Warnings
- —No documentation or OpenAPI spec available for this endpoint
- —No request body schema or response schema provided
- —The endpoint /api/v1/products/80/inventory is not listed among the provider's advertised APIs
- —All doc/pricing/README pages resolve to a minimal 'Connect wallet' stub with no content
- —Purpose and data returned by 'product 80 inventory' are unknown
Citations
- —The x402 challenge returns maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/products/80/inventory
- —The site advertises all APIs at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/products/80/inventory