How do I install the Refactor Module skill?

Run npx skillmds@latest add tmj-90/refactor-module in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Refactor Module safe to use?

This skill has not completed SkillMD's automated safety review yet. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Refactor Module?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Refactor Module free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Refactor Module?

tmj-90 (@tmj-90) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Refactor Module by tmj-90 — Agent Skill

Name: Refactor Module
Author: tmj-90

Refactor Module

Use when a ticket asks to restructure code without changing what it does — extract a function, split a file, rename for clarity, reduce duplication — with behaviour preserved. Invoke for "refactor X", "clean up the Y module", or "extract Z" where no behaviour change is intended.

tmj-90 53946db 2.0 KB Updated Sep 17, 2026

File contents

Refactor a module

A refactor changes structure, not behaviour. The contract: tests are green before you start and green after, with no scope creep into new features or fixes.

Steps

Establish the safety net. Run the suite first (run-tests) and confirm it's green. If the module under refactor is thinly tested, add characterization tests (the add-unit-test skill) that pin the current behaviour before you touch anything.
Read the lore. Call search_lore (Memory MCP) for the repo's module boundaries, layering, and naming conventions so the new structure fits the codebase.
Refactor in small, behaviour-preserving steps — extract, rename, move, dedupe — re-running tests after each step. Keep the public interface stable unless the ticket explicitly allows changing it; update call sites if you do.
Change no behaviour. No new features, no bug fixes, no dependency changes riding along. If you spot a real bug, note it for a separate ticket — don't fix it here.
Confirm green after. Run the full suite and lint (run-tests, run-lint) and confirm identical behaviour and no new failures.
Evidence: before/after passing summaries (proving behaviour preserved) and a diff_summary. Then use the record-evidence skill and submit for review.

Rules

Behaviour-preserving only: tests green before and after, same outcomes.
No scope creep — no features, fixes, or dependency bumps in a refactor ticket.
Keep the public interface stable unless the AC says otherwise.
If you uncover a bug, log it separately; don't fix it inside the refactor.
Run on a branch (the create-branch skill), never a protected branch.

---name: refactor-moduledescription: Use when a ticket asks to restructure code without changing what it does — extract a function, split a file, rename for clarity, reduce duplication — with behaviour preserved. Invoke for "refactor X", "clean up the Y module", or "extract Z" where no behaviour change is intended.---# Refactor a moduleA refactor changes structure, not behaviour. The contract: tests are green before youstart and green after, with no scope creep into new features or fixes.## Steps1. **Establish the safety net.** Run the suite first (`run-tests`) and confirm it's green. If the module under refactor is thinly tested, add characterization tests (the `add-unit-test` skill) that pin the current behaviour before you touch anything.2. **Read the lore.** Call `search_lore` (Memory MCP) for the repo's module boundaries, layering, and naming conventions so the new structure fits the codebase.3. **Refactor in small, behaviour-preserving steps** — extract, rename, move, dedupe — re-running tests after each step. Keep the public interface stable unless the ticket explicitly allows changing it; update call sites if you do.4. **Change no behaviour.** No new features, no bug fixes, no dependency changes riding along. If you spot a real bug, note it for a separate ticket — don't fix it here.5. **Confirm green after.** Run the full suite and lint (`run-tests`, `run-lint`) and confirm identical behaviour and no new failures.6. **Evidence:** before/after passing summaries (proving behaviour preserved) and a `diff_summary`. Then use the `record-evidence` skill and submit for review.## Rules- Behaviour-preserving only: tests green before and after, same outcomes.- No scope creep — no features, fixes, or dependency bumps in a refactor ticket.- Keep the public interface stable unless the AC says otherwise.- If you uncover a bug, log it separately; don't fix it inside the refactor.- Run on a branch (the `create-branch` skill), never a protected branch.

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