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Create a new Next.js API route with validation, error handling, and TypeScript

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Create New API Route

Create a new Next.js API route following modern best practices for solo developers.

Requirements

API Endpoint: $ARGUMENTS

Implementation Guidelines

1. Next.js 15 App Router (Recommended)

Use Route Handlers in app/​api/ directory with TypeScript

2. Validation

  • Use Zod for runtime type validation
  • Validate input early (before DB/​API calls)
  • Return clear validation error messages

3. Error Handling

  • Global error handling with try/​catch
  • Consistent error response format
  • Appropriate HTTP status codes
  • Never expose sensitive error details

4. TypeScript

  • Strict typing for requests/​responses
  • Shared type definitions
  • No any types

5. Security

  • Input sanitization
  • CORS configuration if needed
  • Rate limiting considerations
  • Authentication/​authorization checks

6. Response Format

// Success
{ data: T, success: true }

// Error
{ error: string, details?: unknown, success: false }

Code Structure

Create a complete API route with:

  1. Route Handler File - app/​api/[route]/​route.ts
  2. Validation Schema - Zod schemas for request/​response
  3. Type Definitions - Shared TypeScript types
  4. Error Handler - Centralized error handling
  5. Example Usage - Client-side fetch example

Best Practices to Follow

  • Early validation before expensive operations
  • Proper HTTP status codes (200, 201, 400, 401, 404, 500)
  • Consistent error response format
  • TypeScript strict mode
  • Minimal logic in routes (use services/​utils)
  • Environment variable validation
  • Request/​response logging for debugging
  • No sensitive data in responses
  • No database queries without validation
  • No inline business logic (extract to services)

Generate production-ready code that I can immediately use in my Next.js project.