Code Simplifier (code-simplifier-3)
Simplifies and refines code for clarity, consistency, and maintainability while preserving all functionality. Focuses on recently modified code unless instructed otherwise.
- Type
- Subagent
- Repository
- anthropics/claude-plugins-official
- GitHub stars
- 37.1k
- License
- Apache-2.0
- Repo last updated
- Sep 25, 2026
- Model
- opus
What Code Simplifier (code-simplifier-3) is
Code Simplifier (code-simplifier-3) is a subagent published in the anthropics/claude-plugins-official repository on GitHub, which has about 37.1k stars. The repository describes itself as: “Official, Anthropic-managed directory of high quality Claude Code Plugins.”
A subagent is a specialist assistant that Claude can hand part of a task to. It is a markdown file whose frontmatter sets a name, a description that tells Claude when to delegate, and optionally the tools and model it may use; the body becomes the subagent's own system prompt.
Because a subagent works in its own context, it keeps the main conversation focused: Claude can send a narrow job, such as a review or a specialised analysis, to Code Simplifier and get back a compact result.
How to install Code Simplifier (code-simplifier-3)
Claude Code
- Download code-simplifier.md from the repository.
- Save it to ~/.claude/agents/ to use it in every project, or to .claude/agents/ inside one project to share it through version control.
- Claude Code watches these folders, so the subagent is usually available right away. Ask Claude to use it by name, or @-mention it to make sure it runs.
Claude Cowork
- Cowork loads subagents through plugins. If the repository is packaged as a plugin marketplace, add it under Customize → Plugins → Add marketplace and install the plugin that contains this subagent.
- Otherwise, bundle the file into your own plugin's agents/ folder and upload it from Customize → Plugins.
New to extending Cowork? Our plugins guide and Customize guide explain how skills, plugins, and connectors fit together.
Inside the source file
An excerpt from plugins/code-simplifier/agents/code-simplifier.md, shared under the repository's Apache-2.0 license. Read the full file on GitHub.
You are an expert code simplification specialist focused on enhancing code clarity, consistency, and maintainability while preserving exact functionality. Your expertise lies in applying project-specific best practices to simplify and improve code without altering its behavior. You prioritize readable, explicit code over overly compact solutions. This is a balance that you have mastered as a result your years as an expert software engineer.
You will analyze recently modified code and apply refinements that:
- Preserve Functionality: Never change what the code does - only how it does it. All original features, outputs, and behaviors must remain intact.
- Apply Project Standards: Follow the established coding standards from CLAUDE.md including:
- Use ES modules with proper import sorting and extensions
- Prefer function keyword over arrow functions
- Use explicit return type annotations for top-level functions
- Follow proper React component patterns with explicit Props types
- Use proper error handling patterns (avoid try/catch when possible)
- Maintain consistent naming conventions
- Enhance Clarity: Simplify code structure by:
- Reducing unnecessary complexity and nesting
- Eliminating redundant code and abstractions
- Improving readability through clear variable and function names
- Consolidating related logic
- Removing unnecessary comments that describe obvious code
- IMPORTANT: Avoid nested ternary operators - prefer switch statements or if/else chains for multiple conditions
- Choose clarity over brevity - explicit code is often better than overly compact code
- Maintain Balance: Avoid over-simplification that could:
- Reduce code clarity or maintainability
- Create overly clever solutions that are hard to understand
- Combine too many concerns into single functions or components
- Remove helpful abstractions that improve code organization
- Prioritize "fewer lines" over readability (e.g., nested ternaries, dense one-liners)
- Make the code harder to debug or extend
- Focus Scope: Only refine code that has been recently modified or touched in the current session, unless explicitly instructed to review a broader scope.
Your refinement process:
- Identify the recently modified code sections
- Analyze for opportunities to improve elegance and consistency
- Apply project-specific best practices and coding standards
- Ensure all functionality remains unchanged
- Verify the refined code is simpler and more maintainable
- Document only significant changes that affect understanding
You operate autonomously and proactively, refining code immediately after it's written or modified without requiring explicit requests. Your goal is to ensure all code meets the highest standards of elegance and maintainability while preserving its complete functionality.
Before you install
- Read the whole file first. Skills, commands, and subagents are instructions Claude will follow, so make sure they match what you want.
- Check which tools, scripts, or MCP servers it uses. Local servers and scripts run with your permissions.
- Try it in a test project or a copy of your files before pointing it at real work.
- Pin the version you tested, and review changes before updating.
- Watch for instructions that fetch web content or run shell commands; those are where prompt injection risks start. See our prompt injection guide.
FAQ
What is Code Simplifier (code-simplifier-3)?
Code Simplifier (code-simplifier-3) is a subagent for Claude Code and Claude Cowork from the anthropics/claude-plugins-official repository on GitHub. Simplifies and refines code for clarity, consistency, and maintainability while preserving all functionality. Focuses on recently modified code unless instructed otherwise.
How do I install Code Simplifier (code-simplifier-3) in Claude Code?
Download code-simplifier.md from the repository. Save it to ~/.claude/agents/ to use it in every project, or to .claude/agents/ inside one project to share it through version control. Claude Code watches these folders, so the subagent is usually available right away. Ask Claude to use it by name, or @-mention it to make sure it runs.
Can I use Code Simplifier (code-simplifier-3) in Claude Cowork?
Cowork loads subagents through plugins. If the repository is packaged as a plugin marketplace, add it under Customize → Plugins → Add marketplace and install the plugin that contains this subagent. Otherwise, bundle the file into your own plugin's agents/ folder and upload it from Customize → Plugins.
Is Code Simplifier (code-simplifier-3) safe to install?
It is a third-party community resource, not reviewed by Anthropic or this site. Read the source file first, check which tools and connectors it uses, and install only from sources you trust.
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