Activates automatically when designing or implementing Cloudflare Workers APIs,orchestrating multi-provider API calls, implementing D1 database operations,or managing KV-based caching strategies.Ensures proper error handling, provider tagging, fallback chains, andorchestration patterns for BooksTrack backend infrastructure.Auto-activates on:- File patterns: *.worker.js, *-api.ts, *-service.ts in backend code- Keywords: "api orchestration", "multi-provider", "fallback chain", "D1 query"- Context: Cloudflare Workers development, API design discussions