Refactoring Surgeon

What it does

When your agent uses it

• Tasks that involve Refactoring

Example prompts

• “/refactoring-surgeon”

Requirements

• Node.js
• A Bash shell
• Pre-approved tools (allowed-tools): Read, Write, Edit, Bash(npm test:*,npm run lint:*,git:*)

Workflow steps

10 steps, taken from the step headings in SKILL.md.

1. 1Big Bang Refactoring
2. 2Refactoring Without Tests
3. 3Premature Abstraction
4. 4Renaming Without IDE Support
5. 5Mixing Refactoring and Features
6. 6Ignoring Code Reviews
7. 7Over-Abstracting
8. 8Incomplete Refactoring
9. 9Refactoring Production During Incidents
10. 10Not Measuring Improvement

What it can do on your machine

Read from SKILL.md and the folder at commit 6713fc7. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves these tools, so the agent can use them without asking each time:

  • Read
  • Write
  • Edit
  • Bash(npm test:*
  • npm run lint:*
  • git:*)

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  Ships 1 file in scripts/ (TypeScript and Shell), which the agent can run.

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  Links to these hosts (documentation or services it may open):

  • refactoring.guru
  • refactoring.com
  • oreilly.com

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names no API keys, tokens, secrets or passwords.

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Refactoring Surgeon loads about 1.6k tokens when it runs, and up to ~10k if it reads all its reference files. Until then it costs about 97 tokens; SKILL.md has 495 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~97

When it runs · the whole SKILL.md, loaded when a task matches

~1.6k

With references · SKILL.md plus every file in references/, read only if the agent opens them

~10k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); the scripts in this folder are not scanned.

SKILL.md

The full file from curiositech/some_claude_skills at commit 6713fc7, republished under its MIT licence (© curiositech). 495 words, ~1,605 tokens.

name

refactoring-surgeon

description

Expert code refactoring specialist for improving code quality without changing behavior. Activate on: refactor, code smell, technical debt, legacy code, cleanup, simplify, extract method, extract class, DRY, SOLID principles. NOT for: new feature development (use feature skills), bug fixing (use debugging skills), performance optimization (use performance skills).

allowed-tools

Read, Write, Edit, Bash(npm test:*,npm run lint:*,git:*)

metadata.category

Code Quality & Testing

metadata.tags

refactoring, code-smells, solid, dry, cleanup

┌─────────────────────┐    ┌─────────────────────┐    ┌─────────────────────┐
│    Long Method      │    │    Large Class      │    │   Long Parameter    │
│  > 20 lines?        │    │  > 200 lines?       │    │       List          │
│  → Extract Method   │    │  → Extract Class    │    │  → Parameter Object │
└─────────────────────┘    └─────────────────────┘    └─────────────────────┘

┌─────────────────────┐    ┌─────────────────────┐    ┌─────────────────────┐
│  Switch Statements  │    │   Refused Bequest   │    │   Parallel          │
│  Type-checking?     │    │  Unused inheritance?│    │   Hierarchies       │
│  → Polymorphism     │    │  → Delegation       │    │  → Move Method      │
└─────────────────────┘    └─────────────────────┘    └─────────────────────┘

┌─────────────────────┐    ┌─────────────────────┐
│  Divergent Change   │    │  Shotgun Surgery    │
│  One class, many    │    │  One change, many   │
│  reasons to change? │    │  classes affected?  │
│  → Extract Class    │    │  → Move/Inline      │
└─────────────────────┘    └─────────────────────┘

© curiositech, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

SKILL.md and 7 other files (scripts, references) in .claude/skills/refactoring-surgeon of curiositech/some_claude_skills.

• SKILL.md
• .claude-plugin/plugin.json
• CHANGELOG.md
• references/extract-method.ts
• references/introduce-parameter-object.ts
• references/replace-conditional-polymorphism.ts
• references/strangler-fig-pattern.ts
• scripts/validate-refactoring.sh

Open the folder on GitHubat commit 6713fc7