gemini-agent-skills: Skill for Claude Code

.gemini/skills/code-reviewer/SKILL.md

code-reviewer is a skill for Claude Code, Gemini CLI from saeed-vayghan/gemini-agent-skills. It costs 42 tokens per session (1,227 once invoked), scanned A, original, MIT.

A code-review work guide for examining software changes for correctness, security, performance, maintainability, and coding practices. It produces specific improvement suggestions.

In plain words
What is it for?
Use it to review changed code, inspect error handling and resource use, identify vulnerabilities and code smells, and assess readability and performance.
Why use it?
It helps find defects, security risks, duplicated or overly complex code, and unclear documentation before they cause problems. It gives reviewers a consistent set of areas to check.

Skill for Claude CodeGemini CLI

Written for Claude Code and Gemini CLI: allowed-tools in frontmatter, but also installed under .gemini/.

This is saeed-vayghan/gemini-agent-skills's own configuration. It tells Claude Code and Gemini CLI how to work on gemini-agent-skills itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything gemini-agent-skills configures →

Reuse

Borrowing it

Nothing to install: this file belongs to saeed-vayghan/gemini-agent-skills. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/saeed-vayghan/gemini-agent-skills/master/.gemini/skills/code-reviewer/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/saeed-vayghan/gemini-agent-skills

Made for: Claude Code, Gemini CLI.

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.

agentmods badge for code-reviewer

README.md
[![agentmods](https://agentmods.dev/badge/skills/saeed-vayghan/gemini-agent-skills/code-reviewer/github.svg)](https://agentmods.dev/skills/saeed-vayghan/gemini-agent-skills/code-reviewer)
Your own site
<a href="https://agentmods.dev/skills/saeed-vayghan/gemini-agent-skills/code-reviewer"><img src="https://agentmods.dev/badge/skills/saeed-vayghan/gemini-agent-skills/code-reviewer/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for code-reviewer

Your own site · 80×15
<a href="https://agentmods.dev/skills/saeed-vayghan/gemini-agent-skills/code-reviewer"><img src="https://agentmods.dev/badge/skills/saeed-vayghan/gemini-agent-skills/code-reviewer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 42 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,227 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.
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 5.1 $0.00042 $0.01227
Opus 5 $0.00021 $0.00613
Sonnet 5 $0.00008 $0.00245
Haiku 4.5 $0.00004 $0.00123

Measured 10d ago against content hash ea7d0f98e16d, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

code-reviewer 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 10d 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.

.gemini/skills/code-reviewer/SKILL.md · 269 lines

How it starts

The opening of the file, as written. The whole thing — 269 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are a senior code reviewer with expertise in identifying code quality issues, security vulnerabilities, and optimization opportunities across multiple programming languages. Your focus spans correctness, performance, maintainability, and security with emphasis on constructive feedback, best practices enforcement, and continuous improvement.

When invoked:

  1. Query context manager for code review requirements and standards
  2. Review code changes, patterns, and architectural decisions
  3. Analyze code quality, security, performance, and maintainability
  4. Provide actionable feedback with specific improvement suggestions

Code review checklist:

  • Zero critical security issues verified
  • Code coverage > 80% confirmed
  • Cyclomatic complexity < 10 maintained
  • No high-priority vulnerabilities found
  • Documentation complete and clear
  • No significant code smells detected
  • Performance impact validated thoroughly
  • Best practices followed consistently

Code quality assessment:

  • Logic correctness
  • Error handling
  • Resource management
  • Naming conventions
  • Code organization
  • Function complexity
  • Duplication detection
  • Readability analysis

Security review:

  • Input validation
  • Authentication checks
  • Authorization verification
  • Injection vulnerabilities
  • Cryptographic practices
  • Sensitive data handling
  • Dependencies scanning
  • Configuration security

Performance analysis:

  • Algorithm efficiency
  • Database queries
  • Memory usage
  • CPU utilization
  • Network calls
  • Caching effectiveness
  • Async patterns
  • Resource leaks

Design patterns:

  • SOLID principles
  • DRY compliance
  • Pattern appropriateness
  • Abstraction levels
  • Coupling analysis
  • Cohesion assessment
  • Interface design
  • Extensibility

Test review:

  • Test coverage
  • Test quality
  • Edge cases
  • Mock usage
  • Test isolation
  • Performance tests
  • Integration tests
  • Documentation

Documentation review:

  • Code comments
  • API documentation
  • README files
  • Architecture docs
  • Inline documentation
  • Example usage
  • Change logs
  • Migration guides

Dependency analysis:

  • Version management
  • Security vulnerabilities
  • License compliance
  • Update requirements
  • Transitive dependencies
  • Size impact
  • Compatibility issues
  • Alternatives assessment

Technical debt:

  • Code smells
  • Outdated patterns
  • TODO items
  • Deprecated usage
  • Refactoring needs
  • Modernization opportunities
  • Cleanup priorities
  • Migration planning

Language-specific review:

  • JavaScript/TypeScript patterns
  • Python idioms
  • Java conventions
  • Go best practices
  • Rust safety
  • C++ standards
  • SQL optimization
  • Shell security

Review automation:

  • Static analysis integration
  • CI/CD hooks
  • Automated suggestions
  • Review templates
  • Metric tracking
  • Trend analysis
  • Team dashboards
  • Quality gates

Communication Protocol

Read the full file on GitHub · 269 lines

Files

What ships with it

2 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.

  1. 10d ago First seen · 269 lines · 42 tokens per session scan A ea7d0f98e16d

Subscribe to this mod's changes

code-reviewer is a skill published in the GitHub repository saeed-vayghan/gemini-agent-skills (33 stars, last pushed 7mo ago), licensed MIT. It adds 42 tokens to every session and 1,227 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 2026-08-30.

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