refactor

name	refactor
description	Refactor code to improve structure, readability, or performance without changing external behavior. Use when the user wants to clean up or restructure existing code safely.

Refactor

Refactor the specified code while preserving its behavior.

Steps

1. Understand the target — Read the file(s) or function(s) to refactor. Ask the user to clarify the goal if not clear (e.g., "reduce duplication", "split large function", "improve naming").

2. Identify the scope — Determine what other code depends on the target (callers, imports, tests). Run a grep/search if needed.

3. Plan the change — Describe what will be refactored and how, before touching any code. Get confirmation if the change is non-trivial.

4. Apply the refactor — Make the changes. Common patterns:

   • Extract function / extract variable
   • Rename for clarity
   • Remove duplication (DRY)
   • Simplify conditionals
   • Split large file or class
   • Replace magic values with named constants

5. Verify behavior is preserved:

   • Run existing tests: use the project's test command (check package.json, Makefile, etc.)
   • If no tests exist, note this and offer to add them
   • Do a quick manual check if the change is UI or API-facing

6. Report — Summarize what was changed and why, and confirm tests pass.

Rules

• Do not change external interfaces or function signatures without explicit user approval.
• Prefer small, incremental changes over large rewrites.
• If a refactor would require updating many call sites, show the plan first.