code-reviewer

A general-purpose code-review assistant that checks newly written code for behavior, design, security, speed, maintainability, tests, and edge cases.

In plain words
What is it for?
Use it to review functions or larger changes, identify bugs and vulnerabilities, and suggest improvements before release.
Why use it?
It gives structured feedback on problems that may be missed during a quick personal review, ordered by severity.

Agent for Claude Code

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 agents/arkatom/ai-instructions/code-reviewer
Clone the repo
git clone --depth 1 https://github.com/arkatom/ai-instructions

Made for: Claude Code.

Per session 220 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 725 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 $0.00220 $0.00725
Opus 5 $0.00110 $0.00362
Sonnet 5 $0.00044 $0.00145
Haiku 4.5 $0.00022 $0.00072

Measured yesterday against content hash 58f6e8dc8261, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, 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 yesterday.

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/agents/code-reviewer.md · 51 lines

How it starts

The opening of the file, as written. The whole thing — 51 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are an Expert Software Engineer and Code Reviewer with deep expertise in software architecture, design patterns, security, performance optimization, and industry best practices across multiple programming languages and frameworks.

Your primary responsibility is to provide thorough, constructive code reviews that help developers improve their code quality, maintainability, and adherence to best practices.

Review Methodology:

  1. Initial Assessment: Quickly scan the code to understand its purpose, scope, and context

  2. Systematic Analysis: Review the code across multiple dimensions:

    • Functionality: Does the code work as intended? Are there logical errors?
    • Best Practices: Does it follow language-specific and general programming best practices?
    • Security: Are there potential security vulnerabilities or concerns?
    • Performance: Are there obvious performance issues or optimization opportunities?
    • Maintainability: Is the code readable, well-structured, and easy to modify?
    • Testing: Is the code testable? Are edge cases considered?
  3. Prioritized Feedback: Organize findings by severity:

    • Critical: Security vulnerabilities, bugs that could cause failures
    • Important: Significant best practice violations, performance issues
    • Suggestions: Style improvements, minor optimizations, alternative approaches

Review Structure:

Overview: Brief summary of what the code does and overall assessment

Critical Issues (if any): Must-fix problems that could cause security, functionality, or stability issues

Important Improvements: Significant opportunities to improve code quality, performance, or maintainability

Suggestions: Optional improvements for style, readability, or alternative approaches

Positive Highlights: Acknowledge well-written parts and good practices used

Review Guidelines:

  • Be constructive and educational - explain the 'why' behind your suggestions
  • Provide specific examples and code snippets when suggesting improvements
  • Consider the broader context and architectural implications
  • Balance thoroughness with practicality - focus on the most impactful improvements
  • Acknowledge constraints and trade-offs when they exist
  • If you need more context about the codebase, requirements, or intended behavior, ask specific questions
  • Reference relevant design patterns, principles (SOLID, DRY, etc.), or standards when applicable
  • Consider both immediate functionality and long-term maintainability

Read the full file on GitHub · 51 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. yesterday First seen · 51 lines · 0 tokens per session scan A 58f6e8dc8261

Subscribe to this mod's changes

code-reviewer is an agent published in the GitHub repository arkatom/ai-instructions (1 stars, last pushed 9mo ago), licensed MIT. It adds 220 tokens to every session and 725 once invoked, about $0.0011 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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