Clean Code
Writing readable, maintainable code
Write code that reads like well-written prose using Robert C. Martin's Clean Code principles. This skill equips your AI agent with naming conventions, function design, error handling patterns, and refactoring techniques that make codebases maintainable.
This skill is compatible with Claude, Claude Code, Claude Cowork, Codex, Cursor, OpenClaw, Hermes Agent, and other agentskills.io-compatible agents.
What is the Clean Code skill?
Clean Code is a free AI agent skill built on Robert C. Martin's book. It gives your agent the rules that make code readable — intention-revealing names, functions that do one thing, error handling that doesn't obscure logic — and applies them while it writes and reviews, not in a cleanup pass afterwards.
Key concepts from Clean Code your agent applies
Meaningful Names
Use intention-revealing names for variables, functions, and classes — the name should tell you why it exists.
Small Functions
Functions should do one thing, do it well, and do it only. Keep them short, focused, and at one level of abstraction.
Comments Are a Failure
Good code is self-documenting. If you need a comment, first try to express the intent in code.
Error Handling
Use exceptions rather than return codes. Write try-catch-finally first, then fill in the body.
The Boy Scout Rule
Leave the codebase cleaner than you found it — always make small improvements as you go.
When to use Clean Code — and when not to
Reach for it when
- Your agent writes code that works but reads like it was generated, with names like
data2and 80-line functions. - You're reviewing a pull request and want the naming and function-level problems caught before a human reads it.
- A file has grown to the point where nobody can tell what a function does without reading its whole body.
- You want a consistent style enforced across a codebase several people (and several agents) touch.
Reach for something else when
- The structure is the problem, not the prose — use Clean Architecture for module and dependency boundaries.
- You need named, behaviour-preserving transformations with a safety procedure — that's Refactoring.
- The code has no tests and you daren't touch it — start with Legacy Code, which gets you a safety net first.
- You are trying to reduce interface complexity rather than improve readability — see Software Design.
Example prompts for the Clean Code skill
Review this module for Clean Code violations and suggest refactors using clean-code skill
Code reviewRename these functions and variables to be more intention-revealing using clean-code skill
NamingBreak this 200-line function into clean, single-responsibility functions using clean-code skill
RefactoringRefactor the error handling in this service to follow Clean Code patterns using clean-code skill
Error handlingClean Code vs the other Code Quality skills
All 5 Code Quality skills are free and install the same way — the only question is which framework fits the job in front of you.
| Skill | Based on | Best for |
|---|---|---|
| Clean Code | Clean Code — Robert C. Martin | Writing readable, maintainable code |
| Pragmatic Programmer | The Pragmatic Programmer — Andrew Hunt & David Thomas | Practical software craftsmanship |
| Refactoring | Refactoring — Martin Fowler | Improving code design through systematic refactoring |
| Software Design | A Philosophy of Software Design — John Ousterhout | Reducing complexity through thoughtful software design |
| Legacy Code | Working Effectively with Legacy Code — Michael C. Feathers | Safely change untested code: seams and characterization tests |
Frequently asked questions
How do I install the Clean Code skill?
Run npx skills add wondelai/skills/clean-code --global. It takes about 30 seconds and needs no account. The Clean Code skill then works in Claude, Claude Code, Claude Cowork, Codex, Cursor, OpenClaw and Hermes Agent — anything that reads the open agentskills.io format — and your agent loads it on its own when a task calls for it. It is free and MIT-licensed, and the source is at https://github.com/wondelai/skills.
Which book is the Clean Code skill based on?
It packages Clean Code by Robert C. Martin — co-author of the Agile Manifesto, 50+ years in software. The skill distils the book's method into instructions your agent follows while it works, covering meaningful names, small functions and comments are a failure. It sits in the Code Quality part of the library.
Do I need to have read Clean Code to use this skill?
No. The skill carries the operational parts of the book — the naming heuristics, the function-size rules, the argument against explanatory comments — so your agent applies them whether or not you can quote them. The book is still worth reading for the reasoning and the long worked examples, which is why every page here links it.
How is this different from the Refactoring skill?
Clean Code is about what good code looks like; Refactoring is about how to get there safely. Clean Code will tell your agent that a function is doing three things and should be split. Refactoring gives it the named transformation — Extract Method — and the discipline of small steps with the tests green between each one. They compose well: Clean Code finds the smell, Refactoring performs the surgery.
Will it rewrite my whole codebase if I install it?
No. Skills load when a task calls for them, and they change what your agent does with the code you point it at — nothing runs on its own. In practice you'll see it most in new code your agent writes and in reviews you explicitly ask for. If you want a sweep, ask for one file at a time and keep the diffs reviewable.
Some of Clean Code is contested. Does the skill take a side?
It applies the book's principles as written, including the strong positions on comments and function length. Those are the parts practitioners argue about most. Treat its output as an informed opinion to push back on, not a linter — if your team has settled on different conventions, say so in the prompt and it will follow yours.
Install Clean Code
Free, open-source, and ready in 30 seconds.
npx skills add wondelai/skills/clean-code --global MIT Licensed · Works with Claude, Claude Code, Claude Cowork, Codex, Cursor, OpenClaw, Hermes Agent & other agentskills.io agents · No account needed
Don’t guess your AI engineering level.
Measure it.
AI Developer Scorecard
How production-grade is your AI engineering?
Twenty-five questions across the practices that separate vibe-coding from production-grade engineering. Instant score, per-section breakdown, and a 30/60/90-day playbook.
Score 0–75 · 30/60/90-day playbook Score yourself For CTOs & foundersCTO Scorecard
Is your engineering team ready for AI at scale?
Twenty-five questions on how your org adopts AI — adoption, governance, automation, and ROI. See where you sit on the path from Reactive to Strategic Leader.
Score 0–75 · Reactive → Strategic Leader Score your orgWe build the skills you already use. Now we’ll build yours.
Sprints from $3K · shipped to production, or you don’t pay the final milestone.