id: SKL-0019 name: Refactoring description: | Restructure and clean up existing code without changing behavior. Use this skill when code refactoring is requested, including extracting components, improving naming, and reducing duplication. version: 1.0 owner: fixer triggers:

• REFACTOR_REQUESTED inputs:
• Target files (from active task or event)
• .claude/project/STATE.md
• .claude/project/knowledge/DECISIONS.md
• Existing tests outputs:
• Refactored source files
• .claude/project/STATE.md (updated) tags:
• maintenance
• refactoring
• cleanup

Skill: Refactoring

Metadata

Purpose

Improve internal structure of working code without changing behavior. Behavior before and after: identical. Structure before and after: better.

Procedure

1. Check for existing tests before refactoring:
   • Tests exist: confirm they pass before starting
   • No tests: warn user that refactoring without tests carries risk; request confirmation
2. Define refactor scope narrowly:
   • What specific improvement?
   • What is out of scope?
   • Will any public interface change? If yes: stop — that's a breaking change, not a refactor
3. Refactor in small steps — one improvement at a time:
   • Extract repeated code into functions
   • Rename for clarity
   • Break large functions into smaller ones
   • Remove dead code
   • Simplify conditionals
   • Consolidate duplicated logic
4. Verify behavior unchanged after each step:
   • Run existing tests; if they fail, revert and investigate
   • If no tests: manually verify affected behavior
5. Update STATE.md.

Constraints

• Never changes behavior — only structure
• Never changes public APIs or interfaces
• Always works in small verifiable steps
• Always warns user when no tests exist

Primary Agent

fixer

Definition of Done

• Test status checked before starting
• Refactor scope defined and limited
• No public interfaces changed
• All tests pass after refactoring (or behavior manually verified)
• STATE.md updated

Output Contract