Standardizing Error Messages for Improved Debugging

---
description: Enforce standardized error messages in JavaScript to enhance debugging clarity and developer efficiency.
globs: "**/*.js"
tags: [error-handling, debugging, code-quality]
priority: 2
version: 1.0.0
---

# Standardizing Error Messages for Improved Debugging

## Context
- Applicable to all JavaScript projects.
- Aims to improve error message consistency and informativeness.

## Requirements
- **Use Specific Error Types**: Create and throw custom error classes that extend the native `Error` object to provide more context.
- **Provide Descriptive Error Messages**: Include clear, actionable information in error messages to aid in debugging.
- **Avoid Technical Jargon**: Use plain language in error messages to ensure they are understandable to all developers.
- **Include Relevant Context**: Add pertinent details such as function names, variable values, or operation descriptions to error messages.
- **Implement Consistent Formatting**: Adopt a uniform structure for error messages across the codebase.

## Examples

<example>

// Good: Custom error with descriptive message
class ValidationError extends Error {
  constructor(field, message) {
    super(`Validation failed for field '${field}': ${message}`);
    this.name = 'ValidationError';
    this.field = field;
  }
}

function processUserInput(input) {
  if (!input.email) {
    throw new ValidationError('email', 'Email address is required.');
  }
  // Process input...
}
</example>

<example type="invalid">

// Bad: Generic error with vague message
function processUserInput(input) {
  if (!input.email) {
    throw new Error('Invalid input.');
  }
  // Process input...
}
</example>