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 a collection of endpoints behind per-request USDC micropayments on the Base network. The specific endpoint at `/api/v1/policies/46` is listed as "Premium API Access" and accepts POST requests with an x402 payment header. The x402 challenge indicates a maximum cost of 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 per request (USDC uses 6 decimals). Payment is sent to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second timeout.
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 $0.02 per request with no API keys, no rate limits, and no minimum commitments required.
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 spec, no request/response schema documentation, and no usage examples available from the crawl. The exact functionality behind the `/api/v1/policies/46` endpoint is unclear beyond its "Premium API Access" label. Agents should expect to send a POST with an x402 payment header, but the required request body format and response structure are undocumented.
Capabilities
Use cases
- —Accessing premium API services with per-call USDC micropayments on Base
- —Integrating pay-as-you-go API calls without managing API keys or subscriptions
- —Agent-driven programmatic access to gated endpoints via x402 protocol
Fit
Best for
- —Developers wanting keyless, 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 needing detailed API documentation or OpenAPI specs before integrating
- —Applications requiring high-throughput with predictable flat-rate pricing
- —Developers without access to USDC on the Base network
Quick start
# The endpoint requires an X-PAYMENT header with a valid x402 payment proof.
# POST to the endpoint after constructing the payment:
curl -X POST https://lowpaymentfee.com/api/v1/policies/46 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live (402 challenge captured) and pricing is clear ($0.02 USDC on Base), but there is no OpenAPI spec, no request/response schema, no documentation beyond a wallet-connect prompt, and the purpose of '/api/v1/policies/46' is opaque. Effectively a stub listing.
Warnings
- —No OpenAPI or schema documentation available — request body format and response structure are completely unknown
- —All documentation pages (/docs, /api, /pricing, /README) render only 'Connect wallet' with no technical content
- —The specific purpose of /api/v1/policies/46 ('Premium API Access') is not explained anywhere in the crawled material
- —Cannot verify what data or service this endpoint actually returns
Citations
- —The x402 challenge returns maxAmountRequired of 20000 base units of USDC on Base with a 300-second timeouthttps://lowpaymentfee.com/api/v1/policies/46
- —USDC asset address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/policies/46
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —Four API categories listed: Data & Analytics, AI & Machine Learning, Finance & Web3, Infrastructurehttps://lowpaymentfee.com