safe-refactorlisted

## Purpose Restructure code in small, safe steps while preserving all externally observable behavior. Prevents refactor regressions where behavior silently changes. ## When to Use - Code needs structural improvement but its public API must remain unchanged. - Naming, organization, or duplication needs cleanup after a feature is complete. - Technical debt needs reduction without introducing risk. Do not use this skill if there are no existing tests — write tests first. ## Inputs - Code to refactor. - Existing test suite (required). - Optional: specific goals (extract function, rename module, remove duplication). ## Workflow 1. **Confirm behavior** — Run the test suite. All tests must pass before starting. 2. **Plan** — List the structural changes. Check each for API impact. 3. **Refactor in small steps** — One change at a time, each independently reversible. 4. **Avoid interface changes** — Do not alter public APIs, exported types, or CLI behavior unless explicitly intended. 5. **Validate after each step** — Re-run targeted tests after each meaningful change. ## Output ```markdown Changed: - <structural change 1> - <structural change 2> Behavior unchanged because: <reasoning> Validated by: <test commands run> ``` ## Verification - [ ] Tests pass before starting - [ ] Each step is small and independently reversible - [ ] No unintended API or interface changes introduced - [ ] Tests pass after each meaningful step - [ ] Final test suite fully green ## Failure Mode