x402-gated API platform on Base offering data, AI, finance, and utility endpoints at $0.02/request.
What it does
lowpaymentfee.com is an x402-protocol API marketplace that gates access to a variety of endpoints behind per-request micropayments settled in USDC on the Base network. The specific endpoint at `/api/v1/ehr/81` is listed as "Premium API Access" and accepts POST requests. The x402 challenge indicates a maximum cost of 20,000 base units of USDC (0x8335…), which equals $0.02 per request (USDC uses 6 decimals). No API keys or rate limits are required — callers simply attach an X-PAYMENT header with a valid x402 payment proof.
The broader platform advertises endpoints 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/Utilities (geocoding, validation, conversion, generation). All endpoints are priced at $0.02 per request.
Documentation is extremely sparse. The /docs, /pricing, /api, 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 purpose of the `/api/v1/ehr/81` endpoint (the "ehr" path segment suggests electronic health records) is not documented anywhere on the site, making it unclear what data or functionality this particular endpoint provides.
Capabilities
Use cases
- —Accessing gated API data with per-call USDC micropayments on Base
- —Agent-driven API consumption without pre-registration or API keys
- —Programmatic access to premium data endpoints via x402 protocol
Fit
Best for
- —Developers wanting zero-signup, pay-per-use API access
- —AI agents that can settle x402 payments autonomously
- —Users already holding USDC on Base who need quick API access
Not for
- —Users needing detailed API documentation or response schemas before integrating
- —Applications requiring high-volume, low-latency calls where per-request payment overhead matters
- —Anyone needing clarity on what the /ehr/81 endpoint actually returns before paying
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/ehr/81 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>" \
-d '{}'Endpoint
Quality
The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02 USDC on Base), but there is zero documentation on what the /ehr/81 endpoint accepts or returns. No OpenAPI spec, no examples, no request/response schemas. The docs pages are empty. The 'ehr' path segment is unexplained and potentially refers to electronic health records, which would be a regulated data category.
Warnings
- —No documentation available — /docs, /pricing, /api, and /README all show only 'Connect wallet' with no content
- —The path segment 'ehr' may refer to electronic health records, which is a regulated data category (HIPAA, etc.) — no compliance information is provided
- —No request or response schema is documented; callers cannot know what to send or what they will receive
- —No OpenAPI or machine-readable spec available
- —The endpoint description is generic ('Premium API Access') and does not explain what data or service is provided
Citations
- —The x402 challenge returns maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/ehr/81
- —All endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —The platform offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —Documentation pages (/docs, /pricing, /api, /README) render only a 'Connect wallet' prompthttps://lowpaymentfee.com/docs