Nextjs App Router

Overview

Use this skill to design App Router implementations that are predictable in rendering, caching, and navigation behavior.

Scope Boundaries

• Use this skill when the task matches the trigger condition described in description.
• Do not use this skill when the primary task falls outside this skill’s domain.

Shared References

• Server/client and cache rules:
  • references/server-client-and-cache-rules.md

Templates And Assets

• App Router architecture template:
  • assets/app-router-architecture-template.md
• App Router verification checklist:
  • assets/app-router-checklist.md

Inputs To Gather

• Route hierarchy, layout composition, and navigation requirements.
• Server/client interaction boundaries.
• Freshness, SEO, and caching constraints.
• Error/loading behavior requirements.
• Route param/search param/request payload contracts and ownership boundaries.

Deliverables

• Route/layout map with rendering strategy.
• Data-fetch and cache/revalidation policy.
• Error/loading/not-found boundary plan.
• Verification evidence for transition and consistency behavior.

Workflow

1. Define route/layout architecture in assets/app-router-architecture-template.md.
2. Apply server/client boundary rules from references/server-client-and-cache-rules.md.
3. Parse and normalize route/search/action inputs at boundaries into explicit typed shapes.
4. Configure fetch/cache/revalidation policy per route criticality.
5. Implement explicit loading/error/not-found boundaries.
6. Validate with assets/app-router-checklist.md.

Quality Standard

• Route tree and ownership are explicit.
• Server/client boundaries are minimal and intentional.
• Cache policy matches data freshness requirements.
• Navigation preserves data consistency across transitions.
• Server actions and route handlers avoid repeated cast-heavy shape fixes by using boundary-normalized contracts.

Failure Conditions

• Stop when boundaries between server and client are ambiguous.
• Stop when caching strategy risks stale or inconsistent user state.
• Escalate when critical route behavior cannot be made deterministic.