x402-gated product inventory endpoint on Base, paid per-request in USDC.
What it does
This endpoint at lowpaymentfee.com provides access to a product inventory resource (product ID 90) via the x402 payment protocol. It is part of a broader platform that offers dozens of pay-per-call API endpoints spanning data analytics, AI/ML inference, finance, crypto, and utility services — all gated behind x402 micropayments settled in USDC on the Base network.
The specific endpoint `/api/v1/products/90/inventory` is listed as "Premium API Access" and accepts HTTP POST requests. The x402 challenge indicates a maximum cost of 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 per request (USDC uses 6 decimals). The platform advertises uniform $0.02/request pricing across all its endpoints, with no API keys, no rate limits, and no minimum commitments required.
Documentation is extremely sparse — the docs, pricing, API, 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 inventory data actually contains or what fields the POST body expects. The endpoint is confirmed live (returns a proper 402 challenge), but without documentation it is difficult to know what payload to send or what response to expect.
Capabilities
Use cases
- —Querying product inventory data for product ID 90 via a single micropayment
- —Integrating pay-per-request inventory checks into an agent workflow without API key management
- —Programmatic inventory lookups settled on-chain via USDC on Base
Fit
Best for
- —Agents or apps that need on-demand inventory data without subscription commitments
- —Developers experimenting with x402 micropayment-gated APIs
- —Workflows requiring keyless, per-call API access on Base
Not for
- —Users who need detailed API documentation or response schemas before integrating
- —High-volume inventory polling where $0.02/request adds up quickly
- —Anyone needing non-USDC or non-Base payment options
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/products/90/inventory \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, confirming pricing and payment details. However, there is no documentation, no OpenAPI schema, no request/response examples, and the purpose of the 'Premium API Access' / product inventory endpoint is entirely opaque. This is effectively a stub listing.
Warnings
- —No documentation available — docs, pricing, API, and README pages all show only 'Connect wallet' with no content
- —No OpenAPI or request/response schema provided; request body format and response structure are unknown
- —The endpoint name 'Premium API Access' is generic and does not describe what data is returned
- —Product ID 90 is hardcoded in the URL with no explanation of what product it refers to
Citations
- —The endpoint returns a valid x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/products/90/inventory
- —The platform advertises $0.02/request pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset address on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/products/90/inventory