| name | javascript-best-practices |
| description | Idiomatic JavaScript patterns and conventions for maintainable existing code. Use when reviewing or refactoring JavaScript language patterns; defer project scaffolding, dependency setup, and tool configuration. |
| metadata | {"triggers":{"files":["**/*.js","**/*.mjs"],"keywords":["module","import","export","error","validation"]}} |
JavaScript Best Practices
Priority: P1 (HIGH)
Implementation Guidelines
- Naming:
camelCase (vars/funcs), PascalCase (classes), UPPER_SNAKE (constants).
- Errors: Throw
Error objects only. Handle all async errors.
- Comments: JSDoc for APIs. Explain "why" not "what".
- Files: One entity per file.
index.js for exports.
- Modules: Named exports only. Order: Ext -> Int -> Rel.
Anti-Patterns
- No Globals: Encapsulate state.
- No Magic Numbers: Use
const.
- No Nesting: Guard clauses/early returns.
- No Defaults: Use named exports.
- No Side Effects: Keep functions pure.
Code & Reference
See references/REFERENCE.md for constants, custom errors, async patterns, and module structure examples.
Related Topics
language | tooling
Canonical response anchors
When this skill applies, preserve the following domain terminology or equivalent concrete examples in the answer when relevant:
