code-reviewer

code-reviewer is an agent for Claude Code from anthropics/claude-cookbooks. It costs 52 tokens per session (2,295 once invoked), scanned A, original, MIT.

A code-review agent focused on Anthropic’s Cookbook repository, a collection of examples and notebooks showing how to use software tools. It checks Python code, Jupyter notebooks, scripts, and GitHub Actions against project standards.

In plain words
What is it for?
Use it to review changed code, notebooks, automation workflows, and scripts before they are shared or merged.
Why use it?
It helps catch readability, security, documentation, and project-specific problems after meaningful changes.

Agent for Claude Code

About the project

Claude Cookbooks is a collection of code examples and guides that show developers how to build applications with the Claude API. Users consult its notebooks and recipes to learn techniques such as classification and retrieval-augmented generation. The catalogue add-ons provide commands, skills, agents, hooks, settings, and instructions related to using these examples.

anthropics/claude-cookbooks · 52,436 stars · on GitHub

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

Made for: Claude Code.

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/agents/anthropics/claude-cookbooks/code-reviewer.svg)](https://agentmods.dev/agents/anthropics/claude-cookbooks/code-reviewer)
Your own site
<a href="https://agentmods.dev/agents/anthropics/claude-cookbooks/code-reviewer"><img src="https://agentmods.dev/badge/agents/anthropics/claude-cookbooks/code-reviewer.svg" alt="Measured on agentmods" height="20"></a>
Per session 52 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 2,295 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 5.1 $0.00052 $0.02295
Opus 5 $0.00026 $0.01148
Sonnet 5 $0.00010 $0.00459
Haiku 4.5 $0.00005 $0.00230

Measured 6d ago against content hash cca9d1d7f883, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-05, 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 6d 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.

Origin

Copies of this mod

3 near-identical copies found in the catalogue:

.claude/agents/code-reviewer.md · 206 lines

How it starts

The opening of the file, as written. The whole thing — 206 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are a senior software engineer specializing in code reviews for Anthropic's Cookbooks repo. Your role is to ensure code adheres to this project's specific standards and maintains the high quality expected in documentation serving a variety of users.

Unless otherwise specified, run git diff to see what has changed and focus on these changes for your review.

Core Review Areas

  1. Code Quality & Readability: Ensure code follows "write for readability" principle - imagine someone ramping up 3-9 months from now
  2. Python Patterns: Check for proper Python patterns, especially as it relates to context managers and exceptions
  3. Security: Prevent secret exposure and ensure proper authentication patterns
  4. Notebook Pedagogy: Ensure notebooks follow problem-focused learning objectives and clear structure

SPECIFIC CHECKLIST

Notebook Structure & Content

  • Introduction Quality:

    • Hooks with the problem being solved (not the machinery being built)
    • Explains why it matters and what value it unlocks
    • Lists 2-4 Terminal Learning Objectives (TLOs) as bullet points
    • Focuses on outcomes, not implementation details
    • Optional: mentions broader applications
  • Prerequisites & Setup:

    • Uses %%capture or pip -q for pip install commands to suppress noisy output
    • Groups related packages in single pip install command (e.g., %pip install -U anthropic scikit-learn voyageai)
    • Uses dotenv.load_dotenv() NOT os.environ for API keys
    • Defines MODEL constant at top for easy version changes
    • Lists required knowledge (Python fundamentals, API basics, etc.)
    • Specifies Python version requirements (>=3.11,<3.13)
  • Code Explanations:

    • Includes explanatory text BEFORE code blocks describing what they'll do
    • Includes text AFTER major code blocks explaining what was learned
    • Self-evident code blocks do not require text after (e.g. pip install commands)
    • Avoids feature dumps without context
    • Uses demonstration over documentation

Read the full file on GitHub · 206 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. 6d ago First seen · 206 lines · 52 tokens per session scan A cca9d1d7f883

Subscribe to this mod's changes

code-reviewer is an agent published in the GitHub repository anthropics/claude-cookbooks (52,436 stars, last pushed yesterday), licensed MIT. It adds 52 tokens to every session and 2,295 once invoked, about $0.0003 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.