Trigger: UI change, layout, component architecture, state flow, theming, server/client boundary, Astro island. Keep Next.js or Astro apps server-first.

Astro framework specialist for building fast, content-driven websites with islands architecture. Use when creating Astro components, configuring hydration (client:load/idle/visible/media), using server:defer (server islands), Content Layer API (glob/file loaders, live loaders), sessions, astro:env, i18n routing, actions, SSR adapters, view transitions, or integrating React/Vue/Svelte/Solid. Not for full-SPA frameworks (Next.js, Remix, SvelteKit).

Astro patterns with Clerk — middleware, SSR pages, island components, API routes, static vs SSR rendering. Triggers on: astro clerk, clerk astro middleware, astro protected page, clerk island component, astro API route auth, clerk astro SSR.

Skill for building with the Astro web framework. Helps create Astro components and pages, configure SSR adapters, set up content collections, deploy static sites, and manage project structure and CLI commands. Use when the user needs to work with Astro, mentions .astro files, asks about static site generation (SSG), islands architecture, content collections, or deploying an Astro project.