Runs load tests, profiles application bottlenecks, analyzes response time metrics, and generates performance optimization recommendations. Use when you need to benchmark a system, run load or stress tests, measure latency or throughput, identify performance bottlenecks, optimize Core Web Vitals (LCP, FID, CLS), plan capacity, enforce performance budgets in CI/CD pipelines, or investigate slow API response times, database query performance, or frontend rendering delays.