x402-gated premium API endpoint on Base, pay $0.02 per request in USDC.
What it does
lowpaymentfee.com hosts a collection of x402-protocol pay-per-call API endpoints on the Base network, settling payments in USDC. The specific endpoint `/api/v1/claims/99` is listed as "Premium API Access" and returns a standard x402 402 challenge when called without payment. The site advertises a flat $0.02 per request across all its endpoints, with no API keys, no rate limits, and instant access.
The provider offers endpoints across four categories: Data & Analytics (metrics, reports, data export, insights), AI & Machine Learning (sentiment analysis, text summarization, classification, embeddings), Finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and Infrastructure (geocoding, validation, conversion, generation). All endpoints use the same x402 exact-payment scheme on Base with USDC (contract 0x8335…2913).
The `/api/v1/claims/99` endpoint specifically is not clearly documented beyond the generic "Premium API Access" label. It does not appear in the site's listed API catalog, which raises questions about what data or functionality it actually returns. The x402 challenge confirms it is live and accepts POST requests, with a maxAmountRequired of 20000 base units (i.e., $0.02 USDC given 6 decimals). Documentation pages beyond the landing page returned only a "Connect wallet" prompt with no additional content.
Capabilities
Use cases
- —Accessing premium data or services without traditional API key registration
- —Making one-off API calls settled instantly via USDC on Base
- —Agent-driven workflows that need frictionless pay-per-call access
Fit
Best for
- —Developers who want keyless, pay-as-you-go API access
- —AI agents with Base USDC wallets needing on-demand endpoints
- —Prototyping integrations without subscription commitments
Not for
- —Users who need detailed documentation or guaranteed SLAs before purchasing
- —High-volume consumers who would benefit from bulk pricing or subscriptions
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/claims/99 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, but there is no documentation explaining what /api/v1/claims/99 actually returns, no request/response schema, and the endpoint does not appear in the provider's own catalog. Documentation pages are empty beyond a wallet-connect prompt.
Warnings
- —The endpoint /api/v1/claims/99 is not listed in the provider's public API catalog — its purpose and response format are unknown.
- —All documentation pages (docs, api, pricing, README) returned only 'Connect wallet' with no substantive content.
- —No OpenAPI spec, request schema, or response schema is available.
- —The actual data or functionality behind 'Premium API Access' is unspecified.
Citations
- —The site advertises $0.02 per request with no API keys, no rate limits, and instant access on Base network.https://lowpaymentfee.com
- —The x402 challenge returns maxAmountRequired of 20000 base units in USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base.https://lowpaymentfee.com/api/v1/claims/99
- —The provider lists endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categories.https://lowpaymentfee.com