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name: common-best-practices description: Enforce SOLID principles, guard-clause style, function size limits, and intention-revealing naming across all languages. Use when refactoring for readability, applying clean-code patterns, reviewing naming conventions, or reducing function complexity. metadata: triggers: files: - '/*.ts' - '/.tsx' - '**/.go' - '/*.dart' - '/.java' - '**/.kt' - '/*.swift' - '/*.py' keywords: - solid - kiss - dry - yagni - naming - conventions - refactor - clean code

Global Best Practices

Priority: P0 (CRITICAL)

Core Principles

• SOLID: Follow SRP (One reason to change), OCP (Open to extension), LSP, ISP, DIP.
• KISS/DRY/YAGNI: Favor readability. Abstract repeated logic. No " in case" code.
• Naming: Use intention-revealing names (isUserAuthenticated > checkUser). Match language casing.

Code Hygiene

• Size Limits: Functions < 30 lines. Services < 600 lines. Utils < 400 lines.
• Early Returns: Use guard clauses. Avoid deep nesting.
• Comments: Explain why, not what. Refactor bad code; don't comment it.
• Input: Validate/sanitize all external inputs.

Anti-Patterns

• No Hardcoded Constants: Use named config/env vars.
• No Deep Nesting: Use guard clauses.
• No Global State: Prefer dependency injection.
• No Empty Catches: Always handle, log, or rethrow.

References

• Code Structure Patterns — file/function organization
• Effectiveness Guide — practical application examples