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 78) via the x402 payment protocol. It is gated behind a per-call USDC payment on the Base network. The x402 challenge confirms the endpoint is live and accepts POST requests, returning application/json responses.
The specific endpoint `/api/v1/products/78/inventory` is listed as "Premium API Access" and costs up to $0.02 per request (maxAmountRequired of 20,000 base units of USDC, which has 6 decimals = $0.02). Payment is made in USDC (contract 0x8335…2913 on Base) to address 0x1A2B…85F3 using the "exact" payment scheme. No API keys or rate limits are advertised; access is purely payment-gated.
The broader lowpaymentfee.com platform hosts a variety of x402-gated APIs spanning data analytics, AI/ML inference (sentiment analysis, summarization, classification, embeddings), finance/crypto data feeds, and utility services — all priced at $0.02 per request. However, this specific listing covers only the product inventory endpoint. Documentation on the site is extremely sparse — the docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no further technical detail. There is no OpenAPI spec, no request/response schema documentation, and no example payloads available, so the exact input parameters and response format for this inventory endpoint are unknown.
Capabilities
Use cases
- —Querying inventory levels for a specific product via automated agents
- —Integrating real-time product availability checks into commerce workflows
- —Agent-driven inventory monitoring with per-call micropayments
Fit
Best for
- —Agents needing on-demand product inventory data without API key management
- —Micropayment-based access to inventory information
- —x402-compatible clients on the Base network
Not for
- —Bulk inventory queries requiring thousands of calls (costs add up at $0.02 each)
- —Users who need detailed API documentation or schema validation before integration
- —Non-USDC or non-Base-network payment workflows
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/products/78/inventory \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is confirmed live via a valid x402 402 challenge, and pricing is clear ($0.02 USDC on Base). However, there is no documentation, no OpenAPI spec, no request/response schema, and no examples. The purpose of "product inventory" for product 78 is entirely opaque — it could be a demo or placeholder. The docs pages are empty beyond a wallet-connect prompt.
Warnings
- —No API documentation available — docs, pricing, and README pages all show only 'Connect wallet'
- —No OpenAPI or request/response schema provided; input parameters and response format are unknown
- —The specific product (ID 78) and what 'inventory' returns is undocumented
- —This endpoint path (/api/v1/products/78/inventory) does not appear in the site's listed API catalog, suggesting it may be a demo or unlisted resource
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/products/78/inventory
- —USDC contract address on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/products/78/inventory
- —All listed APIs are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —Documentation pages (docs, API, pricing, README) render only a 'Connect wallet' prompthttps://lowpaymentfee.com/docs