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 access to a variety of endpoints behind per-request USDC micropayments on the Base network. The specific endpoint at `/api/v1/stripe/charges/118` is listed as "Premium API Access" and requires a payment of up to 20,000 base units of USDC (0.02 USD) per call. Payment is made via the x402 exact scheme — no API keys, no rate limits, and no subscriptions are needed.
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 using 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 endpoint is confirmed live (returns a proper 402 x402 challenge), but without documentation it is unclear what request body this specific endpoint expects or what response it returns.
Capabilities
Use cases
- —Paying per-request for data analytics without managing API keys or subscriptions
- —Accessing AI inference endpoints (sentiment, summarization, classification, embeddings) via micropayments
- —Fetching real-time crypto gas estimates or token quotes with USDC micropayments
- —Using geocoding or data conversion utilities on a pay-as-you-go basis
Fit
Best for
- —Developers wanting zero-commitment, pay-per-call API access
- —AI agents that can settle x402 payments autonomously on Base
- —Projects needing lightweight access to multiple API categories without onboarding
Not for
- —Production workloads requiring documented request/response schemas and SLAs
- —Users who need detailed API documentation or OpenAPI specs before integrating
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/stripe/charges/118 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is confirmed live with a valid x402 402 challenge, but documentation is essentially nonexistent — all doc pages show only 'Connect wallet'. There is no OpenAPI spec, no request/response schema, no examples, and the purpose of this specific 'Premium API Access' endpoint at /stripe/charges/118 is unclear. The platform lists many endpoints but provides no technical detail for any of them.
Warnings
- —Documentation pages (/docs, /api, /pricing, /README) are all empty beyond a 'Connect wallet' prompt
- —No OpenAPI or schema documentation available for any endpoint
- —The specific purpose and expected input/output of /api/v1/stripe/charges/118 ('Premium API Access') is undocumented
- —No request or response examples could be obtained
- —The endpoint path includes 'stripe/charges' which may imply Stripe integration but this is unverified
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/stripe/charges/118
- —All listed APIs are priced at $0.02 per 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/118