Next.js Validated Handler Pattern

Type-safe API route handler with automatic Zod validation for Next.js App Router.

When to Use This Skill

Use this skill when:

• Building Next.js API routes (App Router)
• Want automatic input validation with Zod
• Need consistent error handling across API routes
• Want to eliminate boilerplate validation code
• Building type-safe APIs with TypeScript

The Problem

Without a validated handler, every API route has repetitive validation code:

// ❌ REPETITIVE - Every route looks like this
export async function GET(request: NextRequest) {