x402 (www.x402pay.pro) is a minimal DeFi & Trading API provider deployed on the Base network that exposes a single public endpoint (/pong) intended for health-check and connectivity verification. The provider offers a fixed low-cost access model ($0.50 per call) and does not currently surface market data or transactional endpoints. Its primary value is as a lightweight, low-cost heartbeat/ping service for integrations, monitoring, and CI smoke tests for Base-based DeFi apps.