Pay-per-call API platform on Base (USDC) offering data, AI, finance, and utility endpoints at $0.02/request.
What it does
lowpaymentfee.com is an x402-enabled API platform that provides a broad catalog of pay-per-request endpoints settled in USDC on the Base network. The specific endpoint at `/api/v1/messages/131` is listed as "Premium API Access" and costs up to $0.02 per call (20,000 base units of USDC with 6 decimals). Payment is handled via the x402 protocol — no API keys, accounts, or subscriptions are required; callers simply attach an X-PAYMENT header with a valid payment proof.
The wider platform advertises four endpoint 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 the same $0.02/request price point.
Important caveat: the specific `/api/v1/messages/131` endpoint does not clearly map to any of the advertised API categories. Its purpose — whether it retrieves a stored message, triggers a generation, or does something else — is not documented. There is no OpenAPI schema, no request/response examples, and the crawled documentation pages (pricing, README, API) returned only a "Connect wallet" prompt with no further content. Prospective callers should test with a small payment to discover the actual behavior.
Capabilities
Use cases
- —Programmatic access to paid API endpoints without account registration
- —Agent-driven API consumption with per-call USDC micropayments
- —Testing x402 payment flows against a live endpoint
Fit
Best for
- —Developers or agents wanting zero-signup, pay-as-you-go API access
- —x402 protocol experimentation on Base mainnet
- —Low-cost per-request API consumption without rate limits
Not for
- —Users who need detailed API documentation or guaranteed SLAs before paying
- —High-volume batch processing where per-call pricing may add up
- —Anyone without USDC on Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/messages/131 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>"Endpoint
Quality
The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02 USDC on Base), but there is no OpenAPI schema, no request/response examples, no documentation beyond a landing page listing, and the specific /messages/131 endpoint's purpose is undocumented. This is effectively a stub listing.
Warnings
- —No OpenAPI or schema documentation available for this endpoint
- —The /api/v1/messages/131 path does not match any of the advertised API categories on the landing page — its actual function is unknown
- —Documentation pages (/pricing, /README, /api) returned no useful content beyond 'Connect wallet'
- —No request body schema or response examples are available; callers must discover behavior empirically
Citations
- —The endpoint returns a 402 challenge requesting up to 20,000 base units of USDC (asset 0x8335…) on Base networkhttps://lowpaymentfee.com/api/v1/messages/131
- —All listed endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The platform advertises four categories: Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com