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 84) via the x402 payment protocol. It is part of a broader platform that offers dozens of pay-per-request API endpoints 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/84/inventory` is listed as "Premium API Access" and accepts POST requests. The x402 challenge confirms it is live, requiring a maximum payment of 20,000 base units of USDC (0x8335…2913 on Base). Since USDC uses 6 decimals, this translates to $0.02 per request, consistent with the platform's uniform $0.02/request pricing. Payment is made via the x402 exact scheme to the specified payTo address, with a 300-second timeout.
The platform advertises no API keys, no rate limits, and instant access. Documentation pages (/docs, /pricing, /README) appear to require a wallet connection and returned minimal content during crawl, so detailed request/response schemas and parameter documentation are unavailable. The endpoint's actual inventory data format and required POST body fields are not documented in the crawled material, making integration somewhat speculative without experimentation.
Capabilities
Use cases
- —Querying real-time product inventory data for product ID 84
- —Integrating pay-per-request inventory checks into automated purchasing agents
- —Building commerce workflows that need on-demand inventory lookups without subscription commitments
Fit
Best for
- —Agents needing one-off or low-volume inventory queries without API key management
- —Developers exploring x402 micropayment-gated APIs on Base
- —Automated systems that need instant access to product data with no signup
Not for
- —High-volume inventory monitoring where per-request fees would accumulate significantly
- —Users who need detailed API documentation and response schemas before integration
- —Applications requiring non-crypto payment methods
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/products/84/inventory \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>" \
-d '{}'Endpoint
Quality
The endpoint is confirmed live via a valid x402 402 challenge, and pricing is clear ($0.02/request in USDC on Base). However, there is no OpenAPI schema, no documented request/response format, and the docs/pricing/README pages all returned only 'Connect wallet' with no useful content. The endpoint's actual purpose ('Premium API Access' for product 84 inventory) is vague and undocumented.
Warnings
- —No request body schema or response schema available — the POST body format is unknown
- —Documentation pages (/docs, /pricing, /README) require wallet connection and returned no useful content during crawl
- —The endpoint name 'Premium API Access' is generic and does not clarify what inventory data is returned
- —Product ID 84 is hardcoded in the path; it is unclear what product this refers to or whether other product IDs are available
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/products/84/inventory
- —The platform charges $0.02 per request 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/84/inventory