What problem does it solve? Building modern Next.js applications requires navigating App Router conventions, server/client component boundaries, caching strategies, and deployment configuration, which is error-prone without structured guidance. ## Core Features & Use Cases - App Router Architecture: Set up file-based routing with layouts, templates, route groups, parallel routes, and loading/error boundaries. - Server Components & Data Fetching: Implement RSC patterns with fetch caching, ISR, tag-based revalidation, and streaming via Suspense. - Server Actions & Deployment: Build validated form mutations with revalidation, then deploy to Vercel, Docker, or self-hosted Node.js with production optimization. - Use Case: Scaffold a product catalog page that fetches from an API with 60-second ISR, renders via a Server Component with Suspense fallback, and includes a Server Action form for creating products with Zod validation. ## Quick Start Ask the assistant to build a Next.js 14 App Router page that fetches data from an API with revalidation and includes a loading state and error boundary.