Pay-per-call premium API access on Base via x402 — $0.02/request in USDC.
What it does
This endpoint at lowpaymentfee.com provides "Premium API Access" via the x402 payment protocol. The site hosts a collection of pay-per-request APIs spanning data & analytics, AI/ML inference, finance & Web3 data, and infrastructure utilities — all priced at $0.02 per request, settled in USDC on the Base network. No API keys or rate limits are required; callers simply attach an x402 payment header to each request.
The specific endpoint `/api/v1/charges/191` is listed as "Premium API Access" and returns a 402 challenge requesting up to 20,000 base units of USDC (0x8335…2913 on Base, 6 decimals = $0.02) per call. The payment scheme is "exact" with a 300-second timeout. The endpoint accepts POST requests and returns application/json.
While the site advertises a broad catalog of endpoints (metrics, reports, sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, geocoding, validation, conversion, and generation), the specific functionality behind `/api/v1/charges/191` is not documented beyond the generic "Premium API Access" label. No OpenAPI schema, request/response examples, or detailed documentation were found — the docs, pricing, and API pages all render only a "Connect wallet" prompt. This makes it difficult to determine what data or service this particular endpoint returns.
Capabilities
Use cases
- —Accessing premium API services with per-request USDC micropayments on Base
- —Agent-driven API consumption without pre-registration or API keys
- —Programmatic pay-as-you-go access to data or utility endpoints
Fit
Best for
- —Developers wanting keyless, pay-per-use API access
- —AI agents with x402-compatible payment capabilities
- —Users who prefer crypto micropayments over subscription billing
Not for
- —Users who need detailed API documentation or schemas before integrating
- —High-volume use cases where per-request pricing may add up
- —Anyone without a Base-network USDC wallet or x402-compatible client
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/charges/191 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, confirming pricing and payment details. However, there is no documentation, no OpenAPI schema, no request/response examples, and the specific functionality behind this endpoint is entirely undescribed. The docs pages render only a wallet-connect prompt with no useful content.
Warnings
- —No documentation available — docs, pricing, and API pages all show only 'Connect wallet'
- —The specific functionality of /api/v1/charges/191 ('Premium API Access') is not described anywhere
- —No OpenAPI or request/response schema provided
- —No example responses available to verify what data is returned
Citations
- —The site lists APIs across data & analytics, AI/ML, finance & Web3, and infrastructure, all at $0.02/requesthttps://lowpaymentfee.com
- —Pricing is $0.02 per request with no API keys, no rate limits, instant access on Base networkhttps://lowpaymentfee.com
- —The x402 challenge requests maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/charges/191