Guide · Agent skill
How to use the Code Review Specialist agent skill
Updated · written with AI from the project's own documentation and checked against our catalogue data
The Code Review Specialist is an agent skill that gives an AI agent a structured code review routine covering security, performance, code quality and maintainability. This guide explains what a skill is, how to install this one from the downloaded ZIP, how to trigger it with plain requests, and what it needs and does not do. By the end you will be able to ask an agent for a review of a file or pull request and know what kind of report to expect.
Quick start
- 1Download the ZIP. Download the code-review-specialist ZIP from this page.
- 2Choose where to install. Pick ~/.claude/skills/ for all your projects, or a project's .claude/skills/ folder for one project only.
- 3Unzip the skill. Extract the archive into the chosen folder so that SKILL.md sits inside the code-review-specialist folder.
- 4Or upload in the Claude apps. If you use the Claude apps, go to Settings → Capabilities → Skills and upload the ZIP.
- 5Ask for a review. Make a plain request such as reviewing a named file or a pull request for security, performance or quality.
- 6Read the report. Check the 1-5 score, then work through critical issues first, using the listed locations and example fixes.
- 7Verify before acting. Confirm critical findings against the code yourself, and run the Python helper scripts only if you have reviewed them and have Python 3.
What is an agent skill and what does this one do?
An agent skill is a folder of instructions, and sometimes helper scripts, that an AI agent loads when a task matches the skill's description. The skill tells the agent how to approach that kind of task, so you do not have to explain the method every time.
When this skill is active, the agent reviews code the way a senior engineer would. It checks for security issues such as injection, authentication and authorization problems, sensitive data in logs and weak cryptography. It also looks at performance (algorithmic cost, memory, database queries, caching, concurrency) and at quality and maintainability (function length, complexity, naming, documentation, tests).
- Security: authentication and authorization, data exposure, injection, cryptographic weaknesses, logging of sensitive data
- Performance: algorithm efficiency (Big O), memory use, database query patterns, caching opportunities, concurrency problems
- Quality: SOLID principles, design patterns, naming conventions, documentation, test coverage
- Maintainability: readability, function length (the skill asks for under 50 lines), cyclomatic complexity, dependency management, type safety
How do you install the Code Review Specialist skill?
Download the ZIP for code-review-specialist from this page. Then choose one of the two installation routes below.
For Claude Code, unzip the download into your personal skills folder at ~/.claude/skills/, or into a project's .claude/skills/ folder if you want the skill available only in that project. Afterwards the folder should contain the skill's SKILL.md file.
If you use the Claude apps, upload the ZIP under Settings → Capabilities → Skills instead.
- Personal install: ~/.claude/skills/
- Project install: the .claude/skills/ folder inside your project
- Claude apps: Settings → Capabilities → Skills, then upload the ZIP
How do you trigger the skill with natural requests?
You do not need a special command. The agent decides to use the skill when your request matches its description, so ask in ordinary language. The skill's description names these triggers: asking for a code review, asking for code quality analysis, asking to evaluate a pull request, and mentioning security analysis or performance optimization.
Be specific about the scope. Naming a file, a function or a diff helps the agent focus, and saying which concern matters most (security, speed, maintainability) changes the emphasis of the report.
- Review this file for security issues: [paste or name the file]
- Do a code review of the changes in this pull request before I merge
- Analyze the code quality of the payment module and tell me what to refactor
- Check this function for performance problems and algorithmic cost
- Review src/auth/login.py for authentication and logging problems
What does the review report look like?
The skill asks for a fixed structure, which makes reports easy to compare across reviews. Each reviewed piece of code gets a summary with an overall quality score from 1 to 5, a count of findings and the recommended priority areas.
Critical issues, when present, are listed with a clear description, location (file and line number), impact, severity (critical, high or medium), and an example fix. Remaining findings are grouped under security, performance, quality and maintainability, with each group shown only when it has problems.
- Summary: overall score (1-5), number of issues, priority areas
- Critical issues: problem, location, impact, severity, example fix
- Findings by category: security, performance, quality, maintainability
What do the helper scripts do and when should you run them?
The skill includes two small Python scripts. scripts/analyze-metrics.py counts functions, classes and rough complexity in a Python file. scripts/compare-complexity.py compares complexity before and after a change. Both are useful when you want quick numbers to back up the review.
The scripts use simple regex-based counting on Python-style keywords and syntax. Treat their numbers as rough indicators, not exact measurements, and check the script's own header or code for how to pass it a file before running it.
- Requires Python 3, and only if you run the scripts
- Works on Python files only; other languages are not parsed by the scripts
- Counts are approximate and can miss or misreport some constructs
What should you check before using it on real code?
The skill runs scripts, so it is not a purely text-based instruction set. Review the scripts before running them, and run them only in an environment you trust. The skill does not declare any network use, and the provided files mention no API keys or accounts.
The checks are prompt-driven, so the agent's findings depend on the code it is given and on the model running the skill. Do not send sensitive proprietary code to an external service unless your setup has approved that service.
- Runs scripts: yes. Read them first and run them in a trusted environment.
- Uses network: no, according to the skill's documentation.
- Requires: Python 3 for the scripts; no API keys or accounts are mentioned.
- Not a replacement for a real security audit or penetration test.
What tips help you get better reviews?
Give the agent the smallest unit that makes sense: one file, one module or one pull request diff. Smaller scopes produce more precise findings. Name the concern you care about most so the report can prioritize it.
Use the included review checklist and finding template as a reference when you want the review to follow your team's process. Verify every critical finding yourself before acting on it, because the agent can be wrong about context it cannot see.
- Keep scope small: one file or one diff at a time
- State priorities, such as security before style
- Compare results with templates/review-checklist.md and templates/finding-template.md
- Confirm critical findings manually against the code and its context
What people use it for
- Getting a second set of eyes on a pull request before merging
- Checking a single file for injection, authentication or sensitive-data logging problems
- Producing consistent review reports with fixed severity levels for a team
- Getting rough complexity and function counts for a Python file
- Comparing complexity before and after a refactor using the compare script
Frequently asked questions
How do I install the Code Review Specialist skill?
Download the ZIP from this page and unzip it into ~/.claude/skills/ for personal use, or into a project's .claude/skills/ folder for one project. In the Claude apps, upload the ZIP under Settings → Capabilities → Skills instead.
Is the Code Review Specialist skill free?
The skill is published under the MIT licence, which is stated on this page. The provided files do not mention any price, so check the licence text for the terms that apply to you.
What does the Code Review Specialist need to run?
The provided files list Python 3, but only if you run the helper scripts. No API keys or accounts are mentioned, and the skill is documented as not using the network.
Can it replace a security audit or penetration test?
No. The checks are prompt-driven and the scripts use simple regex counting, so they can miss or misreport issues. Use the skill as a second review, not as a substitute for a formal audit or penetration test.
Does it work on JavaScript, Go or other non-Python code?
The agent can review code in other languages, but the helper scripts only parse Python-style keywords and syntax, so their metrics are not meaningful for non-Python files.
Why does the agent not use the skill when I ask for a review?
The agent chooses a skill based on how well your request matches its description. Use words such as code review, pull request, code quality, security analysis or performance optimization, and make sure the skill is installed in the folder the agent reads.
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Our verdict
Use this skill if you want a consistent, structured second review of a file or pull request, especially for Python code where the rough metrics add value. Pick something else if you need a formal security audit, you work mainly with non-Python code and need precise metrics, or you cannot send your code to the service your agent uses.
Download the skill