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 & 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 priced at $0.02 per request, paid in USDC on the Base network with no API keys, no rate limits, and no commitments required.
The specific endpoint `/api/v1/charges/117` is labeled "Premium API Access" and accepts POST requests. The x402 challenge confirms it is live, requesting up to 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. Payment is made via the x402 exact scheme to the specified payTo address, with a 300-second timeout.
Documentation is extremely sparse — the docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no additional technical detail. There is no OpenAPI spec, no request/response schema documentation, and no examples of what the endpoint actually returns. The listing name "Premium API Access" is generic and does not clarify what data or functionality this particular charge endpoint provides versus the other listed APIs. Prospective users should be aware that the actual behavior of `/api/v1/charges/117` is undocumented beyond its title.
Capabilities
Use cases
- —Accessing premium API functionality 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, AI, finance, or utility endpoints
Fit
Best for
- —Developers wanting zero-signup, pay-per-use API access
- —AI agents that can settle x402 payments autonomously on Base
- —Users who prefer crypto micropayments over subscription billing
Not for
- —Users who need detailed API documentation or response schemas before purchasing
- —High-volume consumers who want bulk pricing or subscription discounts
- —Users without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/charges/117 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing, but there is no documentation, no OpenAPI spec, no request/response schema, and no explanation of what this specific endpoint actually does. The site's docs pages are empty beyond a wallet connect prompt. Effectively a stub listing.
Warnings
- —No documentation available — docs, API, pricing, and README pages all show only 'Connect wallet'
- —No OpenAPI or schema describing request parameters or response format
- —The endpoint name 'Premium API Access' is generic; it is unclear what /api/v1/charges/117 specifically returns
- —No examples of successful responses are available
- —The relationship between /api/v1/charges/117 and the other listed API paths is unclear
Citations
- —The endpoint returns a 402 x402 challenge requesting up to 20,000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/charges/117
- —All APIs are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The site offers APIs across data & analytics, AI & ML, finance & Web3, and infrastructure categorieshttps://lowpaymentfee.com
- —USDC contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/charges/117