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 specific resource at `/api/v1/charges/391` accepts POST requests and requires payment of up to 20,000 base units of USDC (0x8335…2913) on the Base network, which equals $0.02 per request (USDC uses 6 decimals). Payment is made via the x402 exact scheme with no API keys, rate limits, or upfront commitments required.
The broader lowpaymentfee.com platform advertises a suite of APIs 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 (geocoding, validation, conversion, generation). All endpoints are listed at $0.02 per request. However, the specific endpoint being listed here (`/api/v1/charges/391`) is labeled generically as "Premium API Access" and does not clearly map to any single named API from the catalog.
Documentation is extremely sparse — the /docs, /api, /pricing, and /README pages all render only a "Connect wallet" prompt with no further technical detail. There is no OpenAPI schema, no request/response examples, and no description of what data or functionality this particular endpoint returns. The endpoint is confirmed live (returns a valid 402 challenge), but the lack of documentation makes it difficult to determine the actual payload or use case.
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 keyless, pay-per-use API access settled in USDC on Base
- —AI agents that can handle x402 payment challenges autonomously
- —Users who prefer crypto micropayments over subscription billing
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —Anyone without a Base-compatible USDC wallet
- —High-volume consumers who need bulk pricing or rate guarantees
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/charges/391 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is confirmed live with a valid x402 402 challenge, and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI schema, no request/response examples, no documentation beyond a wallet-connect prompt, and the endpoint name 'Premium API Access' is generic with no indication of what it actually returns. This is 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 path /api/v1/charges/391 does not match any named API in the site's catalog, making its actual function unclear
- —No request or response examples available anywhere in crawled material
Citations
- —Endpoint returns a valid x402 402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/charges/391
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/charges/391
- —All listed APIs priced at $0.02 per request with no API keys, no rate limits, instant access on Base networkhttps://lowpaymentfee.com
- —Platform offers APIs across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com