Pay-per-call premium API endpoint on Base via x402, settled in USDC at $0.02/request.
What it does
This endpoint at lowpaymentfee.com/api/endpoint-71 is an x402-gated API labeled "Premium API Access." It accepts POST requests and charges 20,000 base units of USDC (0x8335…2913) on the Base network, which equals $0.02 per request (USDC uses 6 decimals). Payment is handled via the x402 exact scheme with no API keys or rate limits required — callers simply attach an X-PAYMENT header with a valid payment proof.
The broader lowpaymentfee.com platform advertises multiple API categories including 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. However, this specific endpoint (/api/endpoint-71) does not correspond to any of the named endpoints on the site's landing page, so its exact functionality is unclear.
The endpoint is live and returns a proper 402 challenge. Documentation pages (/docs, /pricing, /README) all resolve but contain only a "Connect wallet" prompt with no substantive content. There is no OpenAPI schema, no request/response examples, and no detailed documentation describing what this particular endpoint does or what input it expects. The output schema indicates it is a discoverable HTTP POST endpoint returning application/json.
Capabilities
Use cases
- —Programmatic access to a premium API endpoint with per-call USDC micropayments
- —Agent-driven workflows that need keyless, pay-as-you-go API access on Base
- —Testing x402 payment flows against a live endpoint
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents needing keyless API access with crypto micropayments
- —Low-volume, pay-per-use API consumption without subscriptions
Not for
- —Users who need detailed documentation or known input/output schemas before integrating
- —High-volume use cases where $0.02/request adds up without bulk discounts
- —Anyone requiring non-crypto payment methods
Quick start
curl -X POST https://lowpaymentfee.com/api/endpoint-71 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>" \
-d '{}'Endpoint
Quality
The endpoint is live and returns a valid 402 challenge with clear pricing ($0.02 USDC on Base). However, there is no documentation, no OpenAPI schema, no request/response examples, and the specific functionality of /api/endpoint-71 is unknown — it doesn't match any named endpoint on the site. Docs pages are empty stubs.
Warnings
- —The specific endpoint /api/endpoint-71 is not listed among the named APIs on the landing page; its actual functionality is unknown.
- —All documentation pages (/docs, /pricing, /README) contain only a 'Connect wallet' prompt with no substantive content.
- —No OpenAPI schema, request format, or response examples are available — integration requires trial and error.
- —No robots.txt or agents.txt found on the domain.
Citations
- —Endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/endpoint-71
- —USDC contract address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/endpoint-71
- —All listed endpoints priced at $0.02/request with no API keys, no rate limits, instant access on Base networkhttps://lowpaymentfee.com
- —Platform lists APIs across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com