Pay-per-call API platform on Base network via x402 — $0.02/request in USDC.
What it does
lowpaymentfee.com is a pay-per-request API platform that uses the x402 protocol to accept USDC payments on the Base network. The specific endpoint `/api/v1/transactions/395` is listed as "Premium API Access" and returns a 402 challenge requesting up to 20,000 base units of USDC (i.e., $0.02) per call. The platform advertises no API keys, no rate limits, and instant access — you simply attach an x402 payment header to each request.
The broader platform 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 utilities (geocoding, validation, conversion, generation). All endpoints are listed at $0.02 per request.
However, this specific endpoint (`/api/v1/transactions/395`) is labeled generically as "Premium API Access" and does not appear in the site's published API catalog. There is no documentation describing what this particular endpoint returns, what input it expects, or what its output schema looks like. The docs, pricing, and API pages all rendered as empty "Connect wallet" stubs, providing no additional technical detail. Without knowing what data or service this endpoint actually delivers, agents should treat it as an opaque paid endpoint with uncertain functionality.
Capabilities
Use cases
- —Programmatic access to paid API endpoints without traditional API key registration
- —Agent-driven workflows that need to pay per call using USDC on Base
- —Testing x402 payment protocol integrations
Fit
Best for
- —Developers experimenting with x402 pay-per-request patterns
- —AI agents with USDC wallets on Base that need on-demand API access
- —Projects that want to avoid API key management and subscriptions
Not for
- —Users who need detailed documentation or guaranteed SLAs before purchasing
- —Anyone without a Base-network USDC wallet and x402-compatible client
- —High-volume use cases where per-request pricing may be inefficient
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/395 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02 USDC on Base), but there is zero documentation on what this specific endpoint does, what inputs it accepts, or what it returns. The docs pages are empty stubs. The endpoint path '/api/v1/transactions/395' does not appear in the site's published catalog, making its purpose entirely opaque.
Warnings
- —No documentation available — docs, pricing, and API pages all render as empty 'Connect wallet' stubs
- —This specific endpoint (/api/v1/transactions/395) is not listed in the site's published API catalog; its actual functionality is unknown
- —No input or output schema provided beyond 'application/json' mime type
- —No examples of request or response payloads available
Citations
- —The endpoint returns a 402 challenge requesting up to 20,000 base units of USDC ($0.02) on Base networkhttps://lowpaymentfee.com/api/v1/transactions/395
- —The platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —The USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/transactions/395
- —The site offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com