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/transfers/72` is listed as "Premium API Access" and returns a 402 challenge requiring payment of up to 20,000 base units of USDC (i.e., $0.02) per call. No API keys or rate limits are required; callers simply attach an X-PAYMENT header with a valid x402 payment proof.
The broader platform advertises multiple API categories including 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 uniformly priced at $0.02 per request.
However, the specific functionality behind `/api/v1/transfers/72` is unclear — the description is simply "Premium API Access" with no further documentation, input schema, or example responses available. The docs, pricing, and README pages on the site all render only a "Connect wallet" prompt with no substantive content. Without documentation or response examples, the actual behavior of this endpoint cannot be confirmed.
Capabilities
Use cases
- —Accessing paid API endpoints without traditional API key registration
- —Making one-off API calls settled instantly in USDC on Base
- —Agent-driven workflows that need frictionless per-call billing
Fit
Best for
- —Developers who want keyless, pay-as-you-go API access
- —AI agents that can settle x402 payments autonomously
- —Users already holding USDC on the Base network
Not for
- —Users who need detailed documentation or guaranteed SLAs before integrating
- —Anyone without USDC on Base or an x402-compatible payment client
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transfers/72 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, confirming it accepts USDC on Base at $0.02/request. However, there is no documentation, no input/output schema, no example responses, and the actual functionality of '/api/v1/transfers/72' is entirely opaque. The site's docs/pricing/README pages are empty beyond a wallet-connect prompt.
Warnings
- —The specific functionality of /api/v1/transfers/72 is undocumented — 'Premium API Access' is the only description available.
- —No OpenAPI spec, input schema, or response examples are provided anywhere on the site.
- —All documentation pages (docs, pricing, README) render only 'Connect wallet' with no content.
- —The platform lists many endpoint categories (AI, finance, analytics, etc.) but none have verifiable documentation.
Citations
- —Endpoint returns 402 with x402 challenge requiring up to 20,000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/transfers/72
- —USDC asset contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base networkhttps://lowpaymentfee.com/api/v1/transfers/72
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —Multiple API categories listed: Data & Analytics, AI & ML, Finance & Web3, Infrastructurehttps://lowpaymentfee.com