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 29) behind an x402 paywall. It is part of a broader platform offering dozens of 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/29/inventory` is listed as "Premium API Access" and accepts 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 no API keys, no rate limits, and instant access — payment is handled entirely via the x402 protocol's X-PAYMENT header.
Documentation is extremely sparse. The crawled /docs, /api, /pricing, and /README pages all returned 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. The endpoint is confirmed live (402 challenge returned), but without documentation it is unclear what fields the POST body should include or what the response payload looks like.
Capabilities
Use cases
- —Querying product inventory data for product ID 29 via a single micropayment
- —Integrating pay-per-request inventory checks into automated agent workflows
- —Accessing inventory information without API key registration
Fit
Best for
- —Agents that can settle x402 payments in USDC on Base
- —Quick one-off inventory lookups without subscription commitments
- —Developers exploring x402 protocol integrations
Not for
- —Users needing detailed API documentation or schema before integrating
- —High-volume inventory queries where per-request pricing may add up
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/products/29/inventory \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is confirmed live with a valid x402 402 challenge, and pricing is clear ($0.02/request in USDC on Base). However, there is no OpenAPI schema, no request/response examples, and all documentation pages returned only a wallet-connect prompt. The actual purpose and data shape of the 'products/29/inventory' resource is unknown.
Warnings
- —No documentation available — all doc pages return only a 'Connect wallet' prompt
- —No OpenAPI or request/response schema provided
- —The specific data returned by the inventory endpoint is undocumented
- —Purpose of 'product 29' is unexplained; may be a demo or placeholder
Citations
- —The endpoint returns a valid x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/products/29/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/29/inventory