x402-gated API key endpoint on Base, paying $0.02 in USDC per request.
What it does
This endpoint at lowpaymentfee.com provides "Premium API Access" via the x402 payment protocol. It is part of a broader platform that offers a variety of pay-per-call API endpoints spanning data & analytics, 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, settled in USDC on the Base network.
The specific endpoint `/api/v1/apikeys/70` appears to be an API key provisioning or access endpoint. The x402 challenge confirms it is live, accepting POST requests, and requires a payment of up to 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. Payment is sent to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second timeout.
The platform advertises no API keys required, no rate limits, and instant access. Documentation pages (/docs, /pricing, /README) all rendered only a "Connect wallet" prompt with no substantive content, so detailed request/response schemas and usage documentation are unavailable. The actual behavior behind this specific endpoint (what it returns upon successful payment) is not documented in the crawled material.
Capabilities
Use cases
- —Programmatically purchasing or activating API keys via x402 micropayment
- —Agents autonomously acquiring access credentials for downstream API calls
- —Demonstrating x402 payment-gated resource provisioning
Fit
Best for
- —Developers experimenting with x402 payment protocol on Base
- —AI agents that need to self-provision API access without manual signup
- —Micropayment-based API consumption without subscriptions
Not for
- —Users needing detailed API documentation or OpenAPI specs before purchasing
- —High-volume batch operations where per-request pricing may add up
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/apikeys/70 \
-H "X-PAYMENT: <x402-payment-token>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, but documentation pages are empty (only 'Connect wallet'). No OpenAPI spec, no request/response schema, and no explanation of what the endpoint actually returns upon successful payment. The listing is effectively a stub with pricing and liveness confirmed but little else.
Warnings
- —Documentation pages (/docs, /pricing, /README) contain no content beyond 'Connect wallet'
- —No OpenAPI or request/response schema available — actual endpoint behavior is unknown
- —The specific purpose of /api/v1/apikeys/70 (what it returns on successful payment) is undocumented
- —The broader platform lists many endpoints but none have documented schemas
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/apikeys/70
- —All endpoints on the platform 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
- —USDC asset address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base networkhttps://lowpaymentfee.com/api/v1/apikeys/70