refactor

A structured way to change existing code while keeping its behavior covered by tests. Refactoring means improving the code’s structure without intentionally changing what it does.

In plain words
What is it for?
Use it to extract functions or components, rename code across a project, modernize patterns, improve TypeScript types, or analyze a refactoring without changing files.
Why use it?
It maps affected files and dependencies, identifies complexity and technical debt, and assesses risks before making changes. Tests provide a safety net for the refactor.

Skill for Claude CodeCodex

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.

agentmods
npx agentmods add skills/bugrabilge/bilge-development-kit/refactor
Any agent
npx skills add bugrabilge/bilge-development-kit --skill refactor
Clone the repo
git clone --depth 1 https://github.com/bugrabilge/bilge-development-kit

Made for: Claude Code, Codex.

Per session 48 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,018 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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.

ModelPer sessionOnce invoked
Fable 5 $0.00048 $0.01018
Opus 5 $0.00024 $0.00509
Sonnet 5 $0.00010 $0.00204
Haiku 4.5 $0.00005 $0.00102

Measured 2d ago against content hash 7b8ea192066f, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, 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 2d 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.

.claude/skills/refactor/SKILL.md · 167 lines

How it starts

The opening of the file, as written. The whole thing — 167 lines — stays where its author put it; the contents beside it link to each section on GitHub.

/refactor - Systematic Refactoring

$ARGUMENTS


Purpose

This command performs safe, systematic refactoring using the code-archaeologist agent with support from domain specialists.


Sub-commands

/refactor [file/dir]     - Analyze and refactor target
/refactor analyze        - Analysis only, no changes
/refactor extract        - Extract functions/components
/refactor rename         - Rename across codebase
/refactor modernize      - Update to modern patterns
/refactor types          - Add/improve TypeScript types

Behavior

When /refactor is triggered:

Phase 1: Analysis (NO CODE CHANGES)

  1. Invoke code-archaeologist agent

    • Map the code structure
    • Identify anti-patterns and tech debt
    • Assess risk of changes
    • Find dependencies that will be affected
  2. Invoke explorer-agent (if needed)

    • Trace usage across codebase
    • Find all consumers/dependents
  3. Present analysis to user

    ## Refactoring Analysis: [Target]
    
    ### Current State
    - Complexity: [Low/Medium/High]
    - Test Coverage: [X%]
    - Dependencies: [List of affected files]
    
    ### Proposed Changes
    1. [Change with rationale]
    2. [Change with rationale]
    
    ### Risk Assessment
    | Risk | Mitigation |
    |------|------------|
    | [Risk] | [How to mitigate] |
    
    ### Estimated Impact
    - Files changed: X
    - Lines modified: ~Y
    
    Proceed? (Y/N)
    

Phase 2: Safety Net (After Approval)

  1. Invoke test-engineer
    • Write characterization tests (capture current behavior)
    • Verify tests pass on current code
    • These tests protect against regression

Phase 3: Refactor (Sequential, Verified)

  1. Apply changes incrementally

    • One refactoring at a time
    • Run tests after each change
    • If tests fail, revert and investigate
  2. Common refactoring operations:

    Operation When to Use
    Extract function/method Long functions (>30 lines)
    Extract component Component does too many things
    Rename Unclear or misleading names
    Move/reorganize Wrong file location
    Simplify conditionals Nested if/else pyramids
    Replace patterns Class -> Hook, Callback -> Promise
    Add types any types, missing interfaces

Read the full file on GitHub · 167 lines

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.

  1. 2d ago First seen · 167 lines · 48 tokens per session scan A 7b8ea192066f

Subscribe to this mod's changes

refactor is a skill published in the GitHub repository bugrabilge/bilge-development-kit (10 stars, last pushed 4mo ago), licensed MIT. It adds 48 tokens to every session and 1,018 once invoked, about $0.0002 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 2026-08-31.

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