x402-gated API platform on Base offering data, AI, finance, and utility endpoints at $0.02/request via USDC.
What it does
lowpaymentfee.com is an x402-protocol API marketplace that gates a variety of endpoints behind per-request USDC micropayments on the Base network. The specific endpoint at `/api/v1/stripe/charges/171` is listed as "Premium API Access" and costs up to $0.02 per call (20,000 base units of USDC with 6 decimals). Payment is made via the x402 exact scheme — no API keys, no rate limits, and no upfront commitments are required.
The broader platform advertises four categories of APIs: 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 and settle payments to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 in USDC (contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base.
Documentation is extremely sparse — the /docs, /api, /pricing, and /README pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI spec, no request/response schema documentation, and no example payloads available. The specific functionality behind the `/api/v1/stripe/charges/171` path is unclear; the name suggests it may relate to Stripe charge data, but this cannot be confirmed from available materials. The endpoint is live and returns a valid x402 402 challenge.
Capabilities
Use cases
- —Accessing data analytics and metrics via per-request USDC micropayments
- —Running AI inference tasks (sentiment, summarization, classification, embeddings) without API key signup
- —Fetching financial data like token quotes, exchange rates, and gas estimates on a pay-as-you-go basis
- —Using utility services like geocoding and validation with no rate limits
Fit
Best for
- —Developers wanting pay-per-call API access without subscriptions or API keys
- —Agents and bots that can settle x402 payments in USDC on Base
- —Quick prototyping where low-friction, no-signup API access is valuable
Not for
- —Production workloads requiring detailed API documentation and SLAs
- —Users who cannot transact in USDC on the Base network
- —Applications needing guaranteed response schemas or versioned contracts
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/stripe/charges/171 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, but there is no OpenAPI spec, no request/response schema, and no meaningful documentation beyond a landing page listing. The actual functionality of the /api/v1/stripe/charges/171 endpoint is unclear, and all doc pages render only 'Connect wallet' with no content.
Warnings
- —No OpenAPI spec or schema documentation available
- —All documentation pages (/docs, /api, /pricing, /README) render only 'Connect wallet' with no useful content
- —The specific purpose of /api/v1/stripe/charges/171 is unclear — the 'Premium API Access' label is generic
- —No request or response examples are available to verify what this endpoint actually returns
- —Cannot confirm what data or service is provided behind this specific endpoint
Citations
- —The endpoint returns a valid x402 402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/stripe/charges/171
- —All endpoints are listed at $0.02/request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The platform offers APIs in four categories: Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 and payTo address is 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3https://lowpaymentfee.com/api/v1/stripe/charges/171