Tech lead

Refactor planner

Immediate result: A refactor broken into small, safe, independently shippable steps with a test at each step.

Problem it solvesA big refactor done in one go breaks things and stalls for weeks.

Download SKILL.md
Add this skill to
ChatGPTClaudeGeminiPerplexity

You paste

Split UserService (1,800 lines: auth, billing, notifications) into three services

You get

Step 1: add characterization tests for the 12 public methods (no code change).

Step 2: extract NotificationService behind the same interface; UserService delegates.

Step 3: move billing calls… each step ships alone.

About this skill

About Refactor planner

Big-bang refactors break things and stall for weeks. This skill plans the same change as a sequence of small, safe steps, each of which leaves the code working and could ship on its own. For every step it names the test or check that guards it and the risk involved, and it flags steps that need a feature flag or data migration. It favours the strangler pattern over rewrites and includes a rollback plan. Tech leads use it to scope work, write tickets and show stakeholders that a scary refactor can land gradually.

Refactor planner AI skill for Tech lead: you paste "Split UserService (1,800 lines: auth, billing, notifications) into three services" and get "Step 1: add characterization tests for the 12 public methods (no code change)."
Refactor planner — example input and the first lines it returns. Works in ChatGPT, Claude and Gemini.
Job profile
Software engineering · Tech lead
Works in
ChatGPT, Claude, Gemini, Copilot, Claude Code
Format
Agent Skills (SKILL.md)
Price
Free, no sign-up
Install instructions

Copy, paste, send

  1. Cold email writerCopy skillCopied ✓1 Copy the skillPress Copy skill.
  2. ANY AI ASSISTANTSKILLPaste here, then press Enter2 Paste it into a new chatChatGPT, Claude, Gemini or Copilot.
  3. ANY AI ASSISTANT3 Send your inputSend the code or module to refactor and the goal (e.g. split a god class.
The skill — paste this into your AI assistant
# Skill: Refactor planner

You are running the "Refactor planner" skill for me. I work as: Tech lead. What I need from you: a refactor broken into small, safe, independently shippable steps with a test at each step.

## When I send you the code or module to refactor and the goal (e.g. split a god class, remove a dependency)
1. Describe the target structure in a few lines.
2. Break the change into steps that each leave the code working.
3. Name the test or check that guards each step.
4. Flag steps that need a feature flag or a data migration.

## Reply in this format
- Target structure
- Numbered steps (each: change, test, risk)
- Rollback plan

## Rules
- No step may require another step to be done first unless stated.
- Prefer the strangler pattern over rewrites.
- Use only the facts I give you; mark anything you had to assume with [ASSUMPTION].
- If something essential is missing, ask me one short question, then continue.
- No preamble or filler: start with the result.

Confirm you're ready in one line, then wait for me to send the code or module to refactor and the goal (e.g. split a god class, remove a dependency).

Then sendThe code or module to refactor and the goal (e.g. split a god class, remove a dependency). For example: Split UserService (1,800 lines: auth, billing, notifications) into three services

ChatGPT

  1. Fastest: paste the skill as your first message in a new chat, then send your input.
  2. To keep it: open a Project, choose Instructions (or Settings → Personalization → Custom instructions for every chat) and paste it there.
  3. To share it with a team: create a custom GPT and paste the skill into its Instructions.
  4. In the Codex app: copy the skill's folder into ~/.codex/skills/ (or Customize → Skills → Add → Create skill).

Claude

  1. Fastest: paste the skill as your first message in a new chat, then send your input.
  2. To keep it: create a Project, open Project instructions and paste the skill.
  3. As a Claude Skill: download the skill's ZIP, then in Claude open Settings → Skills → Add → Upload skill and choose the file.

Gemini

  1. Fastest: paste the skill as your first message in a new chat, then send your input.
  2. To keep it: open Gems → New Gem, paste the skill into Instructions and save.

Microsoft Copilot

  1. Fastest: paste the skill as your first message, then send your input.
  2. In Microsoft 365 Copilot, save it as a prompt or paste it into an agent's instructions to reuse it.

Any other assistant

  1. Paste the skill as the system prompt or first message in any chat assistant (Perplexity, Meta AI, DeepSeek, Mistral, local models).
  2. Coding agents that read the Agent Skills format (SKILL.md) can load the downloaded file from their skills folder.

Install it permanently

Upload it to Claude, add it to ChatGPT's Codex app, clone it into Claude Code, or download the SKILL.md for any agent. Full guide with screenshots →

Download the ZIP and upload it in Claude. Claude then uses the skill on its own whenever a request matches.

Download ZIP

Quick setup

  1. In Claude, open Settings → Skills (under Customize).
  2. Click Add → Upload skill.
  3. Choose the ZIP — don't unzip it — and make sure the skill is switched on.
Claude Settings with Skills selected under Customize, and the Add menu open showing Upload skill, Create a skill, Create with Claude and Record your screen

Repositoryscienceofapps.com/skills/ai-skills.git · all 200 skills, one folder each, plain git over HTTPS

What it does

The steps it follows

  1. Describe the target structure in a few lines.
  2. Break the change into steps that each leave the code working.
  3. Name the test or check that guards each step.
  4. Flag steps that need a feature flag or a data migration.
What you get back

The reply format

  • Target structure
  • Numbered steps (each: change, test, risk)
  • Rollback plan

Rules it never breaks

  • No step may require another step to be done first unless stated.
  • Prefer the strangler pattern over rewrites.
  • Uses only the facts you give it and marks assumptions.
FAQs

Questions about Refactor planner

What does the Refactor planner skill do?

A big refactor done in one go breaks things and stalls for weeks. The skill fixes that: a refactor broken into small, safe, independently shippable steps with a test at each step.

How do I install Refactor planner in ChatGPT, Claude or Gemini?

Copy the skill and paste it as the first message of a new chat, then send your input. To keep it, paste it into a ChatGPT Project or custom GPT, a Claude Project or a Gemini Gem, or upload the SKILL.md file as a Claude Skill.

What do I send Refactor planner after installing it?

Send the code or module to refactor and the goal (e.g. split a god class, remove a dependency). If something essential is missing, the skill asks you one short question and then continues.

Is the Refactor planner skill free?

Yes. It's free to copy, use and adapt, with no sign-up, and works in the free versions of ChatGPT, Claude, Gemini and Copilot.

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