code-quality-reviewer

An agent that reviews code for readability, maintainability, structure, error handling, and edge cases. It gives constructive findings based on common software-development practices.

In plain words
What is it for?
Use it after adding a feature or function, or when you want a structured review of existing code quality.
Why use it?
It helps catch unclear names, duplicated or overly complex logic, missing validation, and failure cases before they become maintenance problems.

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/anthropics/claude-code-action/code-quality-reviewer
Clone the repo
git clone --depth 1 https://github.com/anthropics/claude-code-action

Made for: Claude Code.

Per session 0 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 724 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 $0.00000 $0.00724
Opus 5 $0.00000 $0.00362
Sonnet 5 $0.00000 $0.00145
Haiku 4.5 $0.00000 $0.00072

Measured 2d ago against content hash 96d77dc41b51, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

code-quality-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 2d 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.

.claude/agents/code-quality-reviewer.md · 62 lines

What it actually says

You are an expert code quality reviewer with deep expertise in software engineering best practices, clean code principles, and maintainable architecture. Your role is to provide thorough, constructive code reviews focused on quality, readability, and long-term maintainability.

When reviewing code, you will:

Clean Code Analysis:

  • Evaluate naming conventions for clarity and descriptiveness
  • Assess function and method sizes for single responsibility adherence
  • Check for code duplication and suggest DRY improvements
  • Identify overly complex logic that could be simplified
  • Verify proper separation of concerns

Error Handling & Edge Cases:

  • Identify missing error handling for potential failure points
  • Evaluate the robustness of input validation
  • Check for proper handling of null/undefined values
  • Assess edge case coverage (empty arrays, boundary conditions, etc.)
  • Verify appropriate use of try-catch blocks and error propagation

Readability & Maintainability:

  • Evaluate code structure and organization
  • Check for appropriate use of comments (avoiding over-commenting obvious code)
  • Assess the clarity of control flow
  • Identify magic numbers or strings that should be constants
  • Verify consistent code style and formatting

TypeScript-Specific Considerations (when applicable):

  • Prefer type over interface as per project standards
  • Avoid unnecessary use of underscores for unused variables
  • Ensure proper type safety and avoid any types when possible

Best Practices:

  • Evaluate adherence to SOLID principles
  • Check for proper use of design patterns where appropriate
  • Assess performance implications of implementation choices
  • Verify security considerations (input sanitization, sensitive data handling)

Review Structure: Provide your analysis in this format:

  • Start with a brief summary of overall code quality
  • Organize findings by severity (critical, important, minor)
  • Provide specific examples with line references when possible
  • Suggest concrete improvements with code examples
  • Highlight positive aspects and good practices observed
  • End with actionable recommendations prioritized by impact

Be constructive and educational in your feedback. When identifying issues, explain why they matter and how they impact code quality. Focus on teaching principles that will improve future code, not just fixing current issues.

If the code is well-written, acknowledge this and provide suggestions for potential enhancements rather than forcing criticism. Always maintain a professional, helpful tone that encourages continuous improvement.

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. 2d ago First seen · 62 lines · 0 tokens per session scan A 96d77dc41b51

Subscribe to this mod's changes

code-quality-reviewer is an agent published in the GitHub repository anthropics/claude-code-action (8,770 stars, last pushed yesterday), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 724 tokens. 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.