Error Handler Generator

Good error handling means custom error classes, proper status codes, and consistent response shapes. This tool generates all of it for your framework.

One command. Zero config. Just works.

Quick Start

npx ai-error-handler express

What It Does

• Generates error middleware for your framework
• Creates custom error classes (NotFoundError, ValidationError, etc.)
• Includes async wrapper to catch promise rejections
• Sets up proper HTTP status codes

Usage Examples

# Express middleware
npx ai-error-handler express

# Fastify in JavaScript
npx ai-error-handler fastify -l javascript

# Next.js API routes
npx ai-error-handler nextjs -o lib/errors.ts

# Koa
npx ai-error-handler koa

Best Practices

• Don't leak stack traces - only show them in development
• Log errors server-side - you need them for debugging
• Use error codes - clients can handle specific codes
• Be consistent - same error shape everywhere

When to Use This

• Starting a new API project
• Standardizing error handling across routes
• Adding proper error responses to a messy codebase
• Setting up error monitoring

Part of the LXGIC Dev Toolkit

This is one of 110+ free developer tools built by LXGIC Studios. No paywalls, no sign-ups, no API keys on free tiers. Just tools that work.

Find more:

• GitHub: https://github.com/LXGIC-Studios
• Twitter: https://x.com/lxgicstudios
• Substack: https://lxgicstudios.substack.com
• Website: https://lxgic.dev

Requirements

No install needed. Just run with npx. Node.js 18+ recommended. Needs OPENAI_API_KEY environment variable.

npx ai-error-handler --help

How It Works

Generates framework-specific error handling code including custom error classes, middleware, and async wrappers. The output follows best practices for each framework.

License

MIT. Free forever. Use it however you want.