Pay-per-call API suite on Base (USDC) covering AI, analytics, finance, and utilities at $0.02/request.
What it does
lowpaymentfee.com is an x402-enabled API platform that offers a broad collection of endpoints spanning data analytics, AI/ML inference, finance/Web3 data, and general infrastructure utilities. Every endpoint is priced at $0.02 per request, paid in USDC on the Base network via the x402 protocol. There are no API keys, no rate limits, and no upfront commitments — callers simply attach an x402 payment header to each request.
The specific endpoint at `/api/v1/messages/90` is listed as "Premium API Access" and follows the same x402 payment pattern. Its exact functionality is not documented beyond the generic title; it may be a messaging or content-retrieval endpoint, but the crawl material does not clarify this. The x402 challenge confirms it is live, accepts POST requests, and requires up to 20,000 base units of USDC (i.e., $0.02) per call, settling to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` on Base.
The broader platform advertises endpoints for sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and data generation — all at the same $0.02 price point. No OpenAPI schema, detailed request/response documentation, or usage examples were found in the crawl.
Capabilities
Use cases
- —Agents that need on-demand API access without pre-registration or API keys
- —Programmatic access to a variety of utility, AI, and data endpoints with crypto micropayments
- —Testing x402 payment flows against a live, low-cost endpoint
Fit
Best for
- —Developers exploring x402 protocol integration
- —AI agents that need keyless, pay-per-call API access
- —Projects wanting low-friction USDC micropayments on Base
Not for
- —Users who need detailed API documentation or guaranteed SLAs
- —Applications requiring high-throughput batch processing with volume discounts
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/messages/90 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>" \
-d '{}'Example
Request
{
"url": "https://lowpaymentfee.com/api/v1/messages/90",
"body": {},
"method": "POST",
"headers": {
"X-PAYMENT": "<x402-payment-token>",
"Content-Type": "application/json"
}
}Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, confirming pricing and network. However, there is no documentation for the specific /api/v1/messages/90 endpoint — no request schema, no response schema, no examples, and no explanation of what 'Premium API Access' actually returns. The broader site lists many endpoints but provides no detail beyond names and prices.
Warnings
- —No documentation found for the /api/v1/messages/90 endpoint beyond the title 'Premium API Access'
- —No OpenAPI schema or request/response examples available for any endpoint on the platform
- —The purpose and expected input/output of this specific endpoint are unknown
- —Multiple crawled pages (api, pricing, README) returned only 'Connect wallet' with no useful content
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/messages/90
- —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 across Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —Payment settles in USDC on Base network to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3https://lowpaymentfee.com/api/v1/messages/90