x402-gated product inventory endpoint on Base, pay-per-call with USDC.
What it does
This endpoint at lowpaymentfee.com provides access to a "Premium API Access" resource at the path `/api/v1/products/6/inventory`. It is part of a broader platform (lowpaymentfee.com) that offers a variety of x402-protocol pay-per-request APIs spanning data analytics, AI/ML inference, finance, crypto, and utility services — all settled on the Base network using USDC.
The specific endpoint `/api/v1/products/6/inventory` accepts POST requests and returns JSON. Based on the x402 challenge, each call costs up to 20,000 base units of USDC (0.02 USD) on Base. The platform advertises no API keys, no rate limits, and instant access — payment is handled entirely via the x402 payment header protocol. The asset used for payment is USDC at contract address `0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913` on Base.
The endpoint's exact functionality is not well-documented. The path suggests it returns inventory data for a specific product (product ID 6), but no request/response schema or documentation beyond the x402 challenge and the landing page listing is available. The broader site's docs, pricing, and API pages all render only a "Connect wallet" prompt with no further content. This limits confidence in what the endpoint actually returns.
Capabilities
Use cases
- —Querying inventory status for a specific product via a single paid API call
- —Integrating pay-per-request inventory checks into an agent workflow without API key management
- —Demonstrating x402 protocol payment flows on Base with USDC
Fit
Best for
- —Agents or services that need on-demand inventory data without subscription commitments
- —Developers experimenting with x402 payment protocol integrations
- —Workflows requiring keyless, pay-as-you-go API access on Base
Not for
- —Users needing detailed API documentation or guaranteed SLAs before integrating
- —High-volume inventory polling where per-request costs would accumulate significantly
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/products/6/inventory \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing, but there is no documentation, no request/response schema, and no examples. The docs/pricing/API pages are empty beyond a wallet-connect prompt. The purpose of this specific endpoint (products/6/inventory) is unclear beyond what the URL path implies.
Warnings
- —No request or response schema available — the actual data returned is unknown
- —Documentation pages (docs, pricing, API, README) all render only 'Connect wallet' with no content
- —The endpoint path suggests product inventory data but no confirmation of what 'product 6' is
- —No OpenAPI spec or AI plugin manifest found
Citations
- —The endpoint returns HTTP 402 with an x402 challenge requiring USDC payment on Basehttps://lowpaymentfee.com/api/v1/products/6/inventory
- —maxAmountRequired is 20000 base units of USDC (USD Coin, 6 decimals = $0.02)https://lowpaymentfee.com/api/v1/products/6/inventory
- —The platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base networkhttps://lowpaymentfee.com/api/v1/products/6/inventory