pi-refactor

name	pi-refactor
description	Refactor code safely using small steps, tests, and proven patterns. Use when the user asks to clean up code, reduce duplication, or improve structure without changing behavior.

pi-refactor

Use this skill when improving internal code quality while preserving behavior.

Goals

• reduce duplication
• improve naming and readability
• simplify control flow
• separate responsibilities
• preserve behavior with tests or verification

Refactor Workflow

1. Understand the current behavior
   • read nearby code and existing tests
   • identify the current contract before touching structure
2. Choose the smallest safe refactor
   • start with one clear improvement
   • avoid mixing feature work with cleanup when possible
3. Preserve behavior
   • add or run tests before large changes
   • prefer small, reversible steps
4. Apply a named pattern
   • make the refactor explainable
5. Verify
   • run tests, lint, or targeted validation

Common Code Smells

• duplicate code
• long function / long parameter list
• unclear naming
• giant conditional blocks
• mixed responsibilities
• feature envy / tight coupling
• temporary variables hiding intent

Common Refactoring Patterns

• Extract Method
• Inline Method
• Rename Variable / Function / Class
• Move Method
• Move Field
• Extract Class
• Inline Class
• Replace Temp with Query
• Introduce Parameter Object
• Preserve Whole Object

Rules

• do not change behavior unless the user explicitly asked for it
• prefer many small refactors over one giant rewrite
• keep public interfaces stable unless a migration plan exists
• when uncertain, stop and explain the risk

Output Expectations

• name the refactor pattern(s) used
• explain why the code is better after the change
• mention validation performed

Resources

See:

• templates/refactor-checklist.md
• templates/pattern-examples.md
• templates/smell-catalogue.md