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 25) 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/25/inventory` accepts POST requests and returns JSON. The x402 challenge advertises a maximum cost of 20,000 base units of USDC (0x8335… on Base), which equals $0.02 per request (USDC uses 6 decimals). The platform's landing page confirms uniform $0.02/request pricing across all endpoints, with no API keys, no rate limits, and no minimum commitments required.
Documentation is extremely sparse — the /docs, /pricing, /api, and /README pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI spec, no request/response schema documentation, and no examples of what the inventory endpoint actually returns. The endpoint is confirmed live (402 challenge captured), but without documentation it is unclear what request body is expected or what inventory data is returned.
Capabilities
Use cases
- —Querying product inventory levels programmatically with per-call USDC micropayments
- —Integrating inventory checks into autonomous agent workflows without API key management
- —Building commerce applications that pay for data access on-demand via x402
Fit
Best for
- —Agents or apps needing keyless, pay-per-call inventory data
- —Developers experimenting with x402 micropayment-gated APIs
- —Use cases where avoiding subscription commitments is preferred
Not for
- —Production systems requiring well-documented request/response schemas
- —High-volume inventory polling where per-call pricing becomes expensive
- —Users who need non-crypto payment options
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/products/25/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 documentation is essentially nonexistent — no request/response schemas, no examples, no OpenAPI spec. The purpose of 'product 25 inventory' is opaque without further context. This is effectively a stub listing.
Warnings
- —No documentation available — /docs, /pricing, /api, and /README all return only a wallet-connect prompt with no content
- —No OpenAPI or schema definition for request body or response format
- —Purpose of 'product 25 inventory' is unclear — may be a demo/placeholder endpoint
- —No information on what data the inventory endpoint actually returns
Citations
- —Uniform $0.02/request pricing, no API keys, no rate limits, instant access, Base networkhttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/products/25/inventory
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/products/25/inventory