Pay-per-call premium API on Base via x402 — $0.02/request in USDC, no API keys required.
What it does
lowpaymentfee.com hosts a collection of pay-per-request API endpoints accessible via the x402 payment protocol on the Base network. The specific endpoint `/api/endpoint-78` is listed as "Premium API Access" and accepts USDC payments on Base. The x402 challenge confirms the endpoint is live, accepting POST requests with a maximum cost of 20,000 base units of USDC (i.e., $0.02 per request). Payment is settled on-chain to a specified wallet address, with a 300-second timeout window.
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 uniformly priced at $0.02 per request. The platform emphasizes no API keys, no rate limits, and instant access.
However, the specific functionality of `/api/endpoint-78` is not documented — it does not correspond to any of the named endpoints listed on the site. The docs, pricing, API, and README pages all returned only a "Connect wallet" prompt with no substantive content. There is no OpenAPI schema, no request/response examples, and no detailed documentation available for this or any other endpoint. The actual capabilities behind this endpoint remain unknown.
Capabilities
Use cases
- —Programmatic access to a premium API endpoint with per-call USDC micropayments
- —Agent-driven workflows that need keyless, on-chain-settled API calls
- —Testing x402 payment protocol integrations on Base
Fit
Best for
- —Developers experimenting with x402 pay-per-call patterns
- —Agents that can settle USDC payments on Base automatically
- —Users who want keyless API access without subscriptions
Not for
- —Anyone needing documented request/response schemas before integrating
- —High-volume use cases where $0.02/call adds up without bulk discounts
- —Users who cannot transact in USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/endpoint-78 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>" \
-d '{}'Endpoint
Quality
The x402 challenge is live and confirms pricing and network details, but the specific endpoint /api/endpoint-78 has no documentation, no schema, no examples, and no description beyond the generic title 'Premium API Access'. All doc pages returned only 'Connect wallet' with no content. This is effectively a stub listing.
Warnings
- —The endpoint /api/endpoint-78 does not match any documented endpoint on the site — its actual functionality is unknown.
- —No OpenAPI schema, request format, or response format is available for any endpoint.
- —All documentation pages (docs, pricing, API, README) returned only a 'Connect wallet' prompt with no substantive content.
- —The platform lists many endpoint categories (AI, finance, analytics, infrastructure) but provides zero technical detail on any of them.
Citations
- —The x402 challenge returns 402 with maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/endpoint-78
- —The site advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/endpoint-78
- —Documentation pages returned only 'Connect wallet' with no contenthttps://lowpaymentfee.com/docs