x402-gated premium API access on Base, pay $0.02 per request in USDC — no keys, no rate limits.
What it does
lowpaymentfee.com hosts a collection of x402-protocol pay-per-call API endpoints on the Base network. The specific endpoint at `/api/v1/policies/19` is listed as "Premium API Access" and returns a standard x402 challenge requesting payment in USDC (contract 0x8335…2913 on Base). The maximum amount required per call is 20,000 base units of USDC (6 decimals), which equals $0.02 USD.
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 and require no API keys, no rate limits, and no upfront commitments — callers simply attach an x402 payment header with each request.
The `/api/v1/policies/19` endpoint specifically accepts HTTP POST requests and returns `application/json`. However, the exact request body schema and response format for this particular endpoint are not documented in the available crawl material. The docs, pricing, and API pages all appear to require wallet connection and provide no additional technical detail beyond the landing page overview.
Capabilities
Use cases
- —Accessing premium API data without traditional API key signup
- —Making one-off API calls with instant USDC micropayments on Base
- —Integrating pay-per-request endpoints into autonomous agent workflows
- —Consuming analytics, AI, finance, or utility APIs with no subscription commitment
Fit
Best for
- —Developers or agents wanting frictionless pay-per-call API access
- —Use cases requiring no rate limits and no upfront commitments
- —x402-compatible clients settling payments on Base in USDC
Not for
- —Users who need detailed API documentation or OpenAPI schemas before integrating
- —High-volume consumers who prefer flat-rate or subscription pricing
- —Callers without access to USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/policies/19 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, confirming pricing and network details. However, there is no OpenAPI schema, no request/response examples, and the docs pages are empty (wallet-gated). The purpose of the specific /policies/19 endpoint is unclear beyond the generic label "Premium API Access."
Warnings
- —No OpenAPI or request/response schema available for this endpoint
- —Documentation pages (docs, pricing, API, README) are all behind a wallet-connect gate and provide no content
- —The exact functionality of /api/v1/policies/19 is undocumented — 'Premium API Access' is vague
- —No examples of expected input or output could be found
Citations
- —The endpoint returns a 402 challenge requesting 20,000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/policies/19
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/policies/19
- —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 in Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com