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 49) via the x402 payment protocol. It accepts POST requests and returns JSON. Payment is settled on the Base network using USDC (contract 0x8335…2913) with a maximum cost of 0.02 USDC per request (20,000 base units at 6 decimals).
The endpoint is part of a broader platform (lowpaymentfee.com) that offers a variety of x402-gated APIs spanning data & analytics, AI/ML inference, finance & Web3 data, and infrastructure utilities — all priced at $0.02 per request. The platform advertises no API keys, no rate limits, and instant access; callers simply attach an x402 payment header to each request.
The specific functionality behind this particular endpoint (/api/v1/products/49/inventory) is not well-documented. The listing title is "Premium API Access" and the path suggests it returns inventory data for a specific product, but no request/response schema, field descriptions, or example payloads are available. The docs, pricing, and API pages on the site all render only a "Connect wallet" prompt with no further technical detail. Prospective callers should be aware that the actual behavior of this endpoint is unclear beyond its payment parameters.
Capabilities
Use cases
- —Querying inventory status for a specific product via micropayment
- —Integrating pay-per-call product data into an agent workflow
- —Demonstrating x402 protocol usage on Base with USDC
Fit
Best for
- —Agents or apps that need on-demand product inventory lookups without API key management
- —Developers experimenting with x402 micropayment-gated APIs on Base
- —Workflows requiring low-cost, no-commitment API access
Not for
- —Users who need detailed API documentation or guaranteed SLAs before integrating
- —Bulk inventory queries across many products (no batch endpoint documented)
- —Anyone needing non-USDC or non-Base payment options
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/products/49/inventory \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>"Endpoint
Quality
The endpoint is live (402 challenge captured) and payment parameters are clear, but there is no documentation of request/response schemas, no examples, and the docs pages are empty. The actual functionality behind 'Premium API Access' for product 49 inventory is opaque.
Warnings
- —No request or response schema available — actual endpoint behavior is unknown
- —All documentation pages (docs, pricing, API, README) render only 'Connect wallet' with no technical content
- —The endpoint path suggests product inventory but the listing title 'Premium API Access' is generic and uninformative
- —No OpenAPI spec or ai-plugin manifest found
Citations
- —The endpoint returns a 402 challenge with x402Version 1, accepting USDC on Base with maxAmountRequired of 20000 base unitshttps://lowpaymentfee.com/api/v1/products/49/inventory
- —The platform advertises $0.02 per request, no API keys, no rate limits, and instant access on the Base networkhttps://lowpaymentfee.com
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/products/49/inventory