A set of guidelines for restructuring existing code so it is easier to understand and maintain. Refactoring means changing code structure without changing what it does.

It is used when splitting up large code sections, reducing coupling, improving names, simplifying logic, organizing data, and reviewing error handling.

It helps identify and reduce problems such as long methods, tangled dependencies, unclear names, and complicated conditions.

refactor — Skill for Claude Code and Codex by pproenca

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent

npx skills add pproenca/dot-skills --skill refactor

Clone the repo

git clone --depth 1 https://github.com/pproenca/dot-skills

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/skills/pproenca/dot-skills/refactor.svg)](https://agentmods.dev/skills/pproenca/dot-skills/refactor)

Your own site

<a href="https://agentmods.dev/skills/pproenca/dot-skills/refactor"><img src="https://agentmods.dev/badge/skills/pproenca/dot-skills/refactor.svg" alt="Measured on agentmods" height="20"></a>

Per session 73 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 1,173 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits

Socket pass 18 May 2026
Snyk pass 18 May 2026
NVIDIA SkillSpector pass 7 Sept 2026

How audits are shown

Origin original No closer match found in the catalogue.

Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

Model	Per session	Once invoked
Fable 5.1	$0.00073	$0.01173
Opus 5	$0.00036	$0.00587
Sonnet 5	$0.00015	$0.00235
Haiku 4.5	$0.00007	$0.00117

Measured 8d ago against content hash fec64e09a27e, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

refactor scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 8d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/.curated/refactor/SKILL.md · 112 lines

How it starts

The opening of the file, as written. The whole thing — 112 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Fowler/Martin Code Refactoring Best Practices

Comprehensive code refactoring guide based on Martin Fowler's catalog and Clean Code principles, designed for AI agents and LLMs. Contains 43 rules across 8 categories, prioritized by impact to guide automated refactoring and code generation.

When to Apply

Reference these guidelines when:

Refactoring existing code to improve maintainability
Decomposing long methods or large classes
Reducing coupling between components
Simplifying complex conditional logic
Reviewing code for code smells and anti-patterns

Rule Categories by Priority

Priority	Category	Impact	Prefix
1	Structure & Decomposition	CRITICAL	`struct-`
2	Coupling & Dependencies	CRITICAL	`couple-`
3	Naming & Clarity	HIGH	`name-`
4	Conditional Logic	HIGH	`cond-`
5	Abstraction & Patterns	MEDIUM-HIGH	`pattern-`
6	Data Organization	MEDIUM	`data-`
7	Error Handling	MEDIUM	`error-`
8	Micro-Refactoring	LOW	`micro-`

Quick Reference

1. Structure & Decomposition (CRITICAL)

struct-extract-method - Extract Method for Long Functions
struct-single-responsibility - Apply Single Responsibility Principle
struct-extract-class - Extract Class from Large Class
struct-compose-method - Compose Method for Readable Flow
struct-function-length - Keep Functions Under 20 Lines
struct-replace-method-with-object - Replace Method with Method Object
struct-parameter-object - Introduce Parameter Object

2. Coupling & Dependencies (CRITICAL)

couple-dependency-injection - Use Dependency Injection
couple-hide-delegate - Hide Delegate to Reduce Coupling
couple-remove-middle-man - Remove Middle Man When Excessive
couple-feature-envy - Fix Feature Envy by Moving Methods
couple-interface-segregation - Apply Interface Segregation Principle
couple-preserve-whole-object - Preserve Whole Object Instead of Fields

Read the full file on GitHub · 112 lines

Files

What ships with it

48 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

8d ago First seen · 112 lines · 73 tokens per session scan A fec64e09a27e

Subscribe to this mod's changes

refactor is a skill published in the GitHub repository pproenca/dot-skills (203 stars, last pushed 23d ago), licensed MIT. It adds 73 tokens to every session and 1,173 once invoked, about $0.0004 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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