Pay-per-call API key generation on Base via x402, settled in USDC at $0.02/request.
What it does
lowpaymentfee.com hosts a collection of pay-per-request API endpoints accessible via the x402 payment protocol on the Base network. This specific endpoint (`/api/v1/apikeys/2`) is listed as "Premium API Access" and accepts POST requests with an x402 payment header. Payment is settled in USDC (contract 0x8335…2913 on Base) with a maximum amount of 20,000 base units, which equals $0.02 per call (USDC uses 6 decimals). No API keys, rate limits, or upfront commitments are required — each call is paid individually.
The broader platform advertises 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 the same $0.02/request price point. However, this listing covers only the `/api/v1/apikeys/2` endpoint, whose exact response payload and purpose ("Premium API Access") is not documented beyond the title. It likely returns an API key or access credential, but the crawled documentation pages were effectively empty (showing only "Connect wallet"), so the precise input/output schema is unknown.
Capabilities
Use cases
- —Acquiring API keys or premium access credentials on a per-call payment basis
- —Agents that need to programmatically purchase access tokens without pre-registration
- —Demonstrating x402 payment protocol integration for pay-per-use services
Fit
Best for
- —Developers experimenting with x402 payment-gated APIs
- —AI agents that need on-demand API credential provisioning
- —Projects wanting zero-commitment, no-signup API access on Base
Not for
- —Users needing detailed documentation or guaranteed SLAs before integrating
- —High-volume use cases where per-request crypto settlement overhead matters
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/apikeys/2 \
-H "X-PAYMENT: <x402-payment-token>" \
-H "Content-Type: application/json"Endpoint
Quality
The x402 challenge is live and pricing is clear ($0.02 USDC on Base), but there is no OpenAPI schema, no documented request/response format, and all documentation pages returned only 'Connect wallet' with no useful content. The purpose of the specific endpoint is ambiguous beyond its title.
Warnings
- —Documentation pages (/docs, /api, /pricing, /README) are effectively empty — they only show 'Connect wallet'.
- —No OpenAPI or schema available; request body format and response structure are unknown.
- —The exact function of /api/v1/apikeys/2 ('Premium API Access') is unclear — it may generate an API key, but this is inferred from the path, not documented.
- —No examples or error handling documentation found.
Citations
- —Endpoint returns HTTP 402 with x402 challenge advertising USDC on Base, maxAmountRequired 20000 base unitshttps://lowpaymentfee.com/api/v1/apikeys/2
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/apikeys/2
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —Platform lists endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com