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 35) via the x402 payment protocol. It is part of a broader platform that offers dozens of pay-per-call APIs spanning data analytics, AI/ML inference, finance, crypto, and utility services — all gated behind x402 micropayments on the Base network using USDC.
The specific endpoint `/api/v1/products/35/inventory` is labeled "Premium API Access" by the provider. The x402 challenge confirms it is live, accepting POST requests, and requires a maximum payment of 20,000 base units of USDC (0.02 USD per request, since USDC uses 6 decimals). Payment is settled on-chain to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` on the Base L2 network. No API keys or rate limits are advertised; access is purely payment-gated.
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 or what fields the POST body expects. The endpoint's exact functionality — whether it returns stock levels, product metadata, or something else — cannot be determined from available material.
Capabilities
Use cases
- —Querying product inventory data for product ID 35 via a single paid API call
- —Integrating pay-per-request inventory checks into automated agent workflows
- —Demonstrating x402 micropayment protocol usage on Base network
Fit
Best for
- —Agents or apps needing on-demand product inventory lookups without subscription commitments
- —Developers experimenting with x402 payment-gated APIs on Base
- —Low-volume, pay-as-you-go inventory queries
Not for
- —High-volume inventory monitoring requiring bulk or subscription pricing
- —Use cases requiring detailed API documentation or guaranteed SLAs
- —Users who need non-crypto payment options
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/products/35/inventory \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing, but there is no documentation, no OpenAPI schema, no request/response examples, and no explanation of what the inventory endpoint actually returns. The listing is effectively a stub with only the payment challenge to go on.
Warnings
- —No API documentation available — docs, pricing, and README pages all return only a wallet-connect prompt with no content.
- —No OpenAPI or JSON schema describing request body or response format for this endpoint.
- —The exact nature of the 'inventory' data returned is unknown; 'Premium API Access' is a generic label.
- —The broader platform lists many endpoints but none have documented schemas or examples.
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/products/35/inventory
- —Platform advertises $0.02 per request, no API keys, no rate limits, instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset contract on Base: 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/products/35/inventory
- —Docs, API, pricing, and README pages return only a 'Connect wallet' prompt with no substantive documentationhttps://lowpaymentfee.com/docs