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 one of many endpoints offered by the lowpaymentfee.com platform, which hosts a collection of pay-per-request APIs spanning data & analytics, AI & machine learning, finance & Web3, and infrastructure utilities — all priced at $0.02 per call settled in USDC on the Base network.
The specific endpoint `/api/v1/apikeys/38` appears to be an API-key provisioning or access endpoint. The x402 challenge confirms it is live, accepts POST requests, and requires an exact payment of 20,000 base units of USDC (0x8335…2913 on Base, 6 decimals → $0.02) per call. Payment is sent to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second timeout. No API keys or rate limits are advertised; access is granted purely through the x402 payment header.
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, and no usage examples available from the crawl. The platform's landing page lists sibling endpoints (sentiment analysis, summarization, geocoding, price feeds, etc.) but provides no detail on request formats or response payloads for any of them. Prospective users should expect to experiment or contact the provider for integration guidance.
Capabilities
Use cases
- —Programmatically obtaining API keys or access tokens via a single micropayment
- —Agents purchasing on-demand API access without pre-registration
- —Integrating pay-per-request infrastructure into automated workflows
Fit
Best for
- —AI agents needing instant, keyless API access via x402
- —Developers who want to avoid subscription commitments and pay per call
- —Web3-native applications settling microtransactions on Base
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —High-volume consumers who would benefit from bulk pricing or subscriptions
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/apikeys/38 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>"Endpoint
Quality
The x402 challenge is live 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 no examples. The purpose of this specific endpoint (apikeys/38) is ambiguous. Effectively a stub listing.
Warnings
- —No OpenAPI spec or request/response schema available
- —All documentation pages (/docs, /api, /pricing, /README) render only 'Connect wallet' with no content
- —The exact purpose and expected input/output of /api/v1/apikeys/38 is unclear — 'Premium API Access' is vague
- —No examples or integration guides found
Citations
- —The endpoint returns a valid x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/apikeys/38
- —All 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 endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —USDC contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 with 6 decimalshttps://lowpaymentfee.com/api/v1/apikeys/38