x402-gated product inventory endpoint on Base, pay-per-call with USDC.
What it does
This endpoint at lowpaymentfee.com provides access to a product inventory resource (product ID 72) via the x402 payment protocol. It is one of many endpoints offered by the lowpaymentfee.com platform, which hosts a variety of pay-per-request APIs spanning data analytics, AI/ML inference, finance, and utility services — all gated behind x402 micropayments settled in USDC on the Base network.
The specific endpoint `/api/v1/products/72/inventory` is described as "Premium API Access" and accepts POST requests. Payment is required per call: the x402 challenge advertises a maxAmountRequired of 20,000 base units of USDC (the asset at 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base, which uses 6 decimals), equating to $0.02 per request. No API keys or rate limits are advertised; access is granted purely through the x402 payment header.
Documentation is extremely sparse. The crawled docs, API, pricing, and README pages all returned only a "Connect wallet" prompt with no further content. There is no OpenAPI schema, no request/response examples, and no description of what the inventory data actually contains or what fields the POST body expects. The endpoint is confirmed live (returns HTTP 402 with a valid x402 challenge), but without documentation it is difficult to know what data is returned or what input is required beyond the payment header.
Capabilities
Use cases
- —Querying inventory status for a specific product via micropayment
- —Integrating pay-per-call product data into an agent workflow
- —Accessing gated commercial data without API key registration
Fit
Best for
- —Agents that can settle x402 payments in USDC on Base
- —Use cases requiring keyless, per-request API access
- —Developers exploring x402 protocol integrations
Not for
- —Users needing detailed API documentation or schemas before integration
- —High-volume inventory queries where per-call pricing may add up
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/products/72/inventory \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is confirmed live with a valid x402 challenge, but documentation is essentially nonexistent — no OpenAPI spec, no request/response schema, no description of what 'product 72 inventory' actually returns. The listing is effectively a stub with only pricing and protocol details available.
Warnings
- —No API documentation available; docs, pricing, and README pages all render only a wallet-connect prompt
- —No request body schema or response schema documented — callers must guess at the expected input
- —The meaning of 'Premium API Access' and 'products/72/inventory' is unexplained; unclear what data is returned
- —No OpenAPI or ai-plugin manifest found
Citations
- —The endpoint returns HTTP 402 with a valid x402 challenge advertising USDC on Basehttps://lowpaymentfee.com/api/v1/products/72/inventory
- —maxAmountRequired is 20000 base units of USDC (6 decimals) = $0.02 per requesthttps://lowpaymentfee.com/api/v1/products/72/inventory
- —The platform advertises $0.02/request pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —Docs, API, pricing, and README pages return only a 'Connect wallet' prompt with no substantive contenthttps://lowpaymentfee.com/docs