---
name: coding-practices
description: Code quality practices: error handling, validation, logging, and DRY. Use when writing or reviewing code.
---
# Coding Practices
Guidelines for writing maintainable, robust, and self-documenting code.
## Quick Start
```typescript
// Self-documenting with proper error handling
function createUser(email: string, age: number): User {
if (!email.includes("@")) throw new Error("Invalid email");
if (age < 0 || age > 150) throw new Error("Invalid age");
return { email, age };
}
```
## Key Principles
- Use meaningful names (self-documenting code)
- Comments explain "why", not "what"
- DRY: abstract when used 3+ times
- Validate all input data
- Handle all error cases with proper Error objects
- Never ignore errors
- Use named constants instead of magic values
- Avoid circular dependencies
## References
See [rules.md](references/rules.md) for complete guidelines with examples.
