Cloudflare API Shield is a comprehensive API security and monitoring platform that operates across Cloudflare's global network of 330 locations. The solution automatically discovers public API endpoints and their schemas using machine learning models and heuristics, including shadow APIs that may be unmanaged or unsecured. It provides protection against OWASP Top 10 API security risks, including zero-day exploits, authentication abuse, data loss, DDoS attacks, and business logic attacks. The platform validates incoming requests against OpenAPI schemas, authentication requirements, and legitimate API business logic to block malformed requests and HTTP anomalies. API Shield continuously scans response payloads to prevent data exfiltration and sensitive data leaks. It consolidates API inventory management, policy configuration, analytics, and reporting on a single platform. The solution implements a positive security model that only accepts traffic conforming to defined schemas while blocking malicious or anomalous requests. By filtering out invalid API traffic, it helps reduce API hosting costs by ensuring backend systems only process legitimate requests. API Shield integrates with Cloudflare's web application services to provide unified security across applications and APIs.