Pay-per-call premium API on Base via x402 — $0.02/request in USDC, no API keys required.
What it does
This endpoint at lowpaymentfee.com/api/endpoint-83 is an x402-gated API labeled "Premium API Access." The provider's site advertises a broad suite of 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 with no API keys, no rate limits, and no commitments.
The specific endpoint probed (/api/endpoint-83) returned a valid x402 challenge with maxAmountRequired of 20,000 base units of USDC (0x8335…2913 on Base, 6 decimals), which equals $0.02 per call. Payment is made via the x402 "exact" scheme to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second timeout. The endpoint accepts HTTP POST and returns application/json.
However, the crawled documentation pages (/docs, /api, /pricing, /README) all returned only a "Connect wallet" prompt with no actual documentation, schemas, or usage examples. It is unclear what specific functionality /api/endpoint-83 provides — the path does not match any of the named endpoints listed on the homepage. Without request/response schemas or documentation, callers cannot know what payload to send or what data to expect back.
Capabilities
Use cases
- —Agent-initiated pay-per-call API access without API key management
- —Programmatic micropayment-gated data retrieval on Base
- —Testing x402 payment flows with low-cost endpoints
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents needing keyless, pay-as-you-go API access
- —Low-cost per-request usage without subscriptions
Not for
- —Users who need documented request/response schemas before integrating
- —High-throughput batch processing where per-call costs add up
- —Anyone requiring detailed API documentation or SLAs
Quick start
curl -X POST https://lowpaymentfee.com/api/endpoint-83
# Returns 402 with x402 challenge; include X-PAYMENT header with USDC payment proof on Base to access.Endpoint
Quality
The endpoint is live and returns a valid x402 challenge at $0.02/request in USDC on Base. However, there is no documentation, no request/response schema, and /api/endpoint-83 does not correspond to any named endpoint on the site. The docs, pricing, and README pages are all empty (just 'Connect wallet'). This is effectively a stub listing.
Warnings
- —No documentation available — all doc pages return only 'Connect wallet'
- —/api/endpoint-83 does not match any of the named endpoints listed on the homepage
- —No request or response schema provided; callers cannot determine what payload to send
- —Provider site lists many endpoints but none with detailed specs or examples
Citations
- —All endpoints priced at $0.02 per request with no API keys, no rate limits, instant access on Base networkhttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/endpoint-83
- —Provider lists endpoints for analytics, AI/ML, finance/Web3, and infrastructure utilitieshttps://lowpaymentfee.com
- —Documentation pages (/docs, /api, /pricing, /README) contain only 'Connect wallet' with no contenthttps://lowpaymentfee.com/docs