Nw Refactor Agent Skill

NW-REFACTOR: Systematic Code Refactoring

Wave: CROSS_WAVE

Agent: Crafty (nw-software-crafter)

Command: *refactor

Overview

Applies the Refactoring Priority Premise (RPP) — 6-level hierarchy L1 Readability|L2 Complexity|L3 Responsibilities|L4 Abstractions|L5 Design Patterns|L6 SOLID++. For complex multi-class refactorings, agent applies Mikado Method internally.

Execution Model — Batch-Then-Verify (default, unconditional)

/nw-refactor runs batch-then-verify by default, regardless of test-suite speed:

• Cascade governs PLANNING ORDER only — analyze and plan lower levels before higher (L2 transformations build on L1, L3 on L2, etc.). The cascade is a planning discipline, not a test-gating sequence.
• Edits applied as one coherent batch — apply all planned L1-L6 transformations in a single editing session. NO interleaved test runs between levels.
• Run the test suite exactly ONCE, at the very end, after all L1-L6 edits.
• If RED after the batch: diagnose the breakage and fix the production code. Do NOT modify tests to make them pass. A test that must change to pass means either (a) the refactor altered observable behavior — revert that transformation — or (b) the test encoded an implementation detail rather than behavior — flag this to the user explicitly before touching it. Tests changing during a refactor is a signal, not a step.

Legacy incremental variant (opt-in only): the nw-progressive-refactoring skill documents the incremental L1→test→L2→test cycle. It is NOT the default — use it only when explicitly requested. Anchor: feedback_refactor_batch_when_test_suite_slow_2026_05_19 (the prior "only batch when suite slow" conditional is removed — batch is now unconditional).

Context Files Required

• src/\* - Production codebase
• tests/\* - Test codebase

Agent Invocation

@nw-software-crafter

Execute \*refactor for {target-class-or-module}.

Context Files:

• src/\*
• tests/\*

Configuration:

• level: 3 # Shorthand: --from=1 --to=3 (RPP range)
• from: 1 # Start RPP level (default: 1)
• to: 3 # End RPP level (default: same as level)
• scope: module # file/module/project
• method: extract # extract/inline/rename/move
• mikado_planning: false # Use Mikado Method for complex refactorings

Progress Tracking

The invoked agent MUST create a task list from its workflow phases at the start of execution using TaskCreate. Each phase becomes a task with the gate condition as completion criterion. Mark tasks in_progress when starting each phase and completed when the gate passes. This gives the user real-time visibility into progress.

Success Criteria

• [ ] Code quality metrics improved (measured before/after)
• [ ] L1-L6 transformations planned in cascade order, applied as one batch
• [ ] Test suite run exactly once, at the end — GREEN
• [ ] If RED after batch: production code fixed (tests NOT modified to pass)
• [ ] Technical debt reduced measurably

Next Wave

Handoff To: {invoking-agent-returns-to-workflow}

Deliverables: Refactored codebase with quality improvements

Examples

Example 1: Module-level readability refactor

/nw-refactor src/auth/token_manager.py --level=2 --scope=module

Crafty applies RPP L1-L2: rename ambiguous variables|extract magic numbers into constants|remove dead code (L1), then simplify conditionals|extract long methods (L2).

Example 2: SOLID-level design refactor

/nw-refactor src/billing/ --level=6 --scope=module --mikado_planning=true

Crafty uses Mikado Method for multi-class refactoring, applies dependency inversion|interface segregation across billing module.

Example 3: RPP range sweep (L1-L3)

/nw-refactor src/des/domain/ --from=1 --to=3 --scope=module

Sweeps L1 readability|L2 complexity|L3 responsibility smells. Cascade governs planning order (analyze L1 before L2 before L3); edits applied as one batch; suite run once at the end.

Example 4: Targeted single-level refactor

/nw-refactor src/des/cli/verify.py --level=3 --scope=file

Targets L3 responsibility smells only (Large Class, Feature Envy, Shotgun Surgery). Assumes L1-L2 already clean.

Expected Outputs

src/*                              (refactored production code)
tests/*                            (refactored test code)
docs/refactoring/
  refactoring-log.md
  quality-metrics.md