code-review

A review of an existing code change, such as a patch, commit, pull request, or working-tree difference. It checks whether the change works correctly and safely within the project's existing conventions.

In plain words
What is it for?
Use it to inspect proposed changes, understand their effect on related modules and interfaces, and identify important problems without changing the code.
Why use it?
It helps catch defects, regressions, security problems, data risks, compatibility issues, and missing tests before the change is accepted.

Skill for Claude CodeCodex

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 skills/arroyo-gonzalo/codex-devkit/code-review
Any agent
npx skills add Arroyo-Gonzalo/codex-devkit --skill code-review
Clone the repo
git clone --depth 1 https://github.com/Arroyo-Gonzalo/codex-devkit

Made for: Claude Code, Codex.

Per session 60 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,375 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 $0.00060 $0.01375
Opus 5 $0.00030 $0.00687
Sonnet 5 $0.00012 $0.00275
Haiku 4.5 $0.00006 $0.00137

Measured 2d ago against content hash 43a13e643356, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

code-review 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.

skills/code-review/SKILL.md · 287 lines

How it starts

The opening of the file, as written. The whole thing — 287 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Code Review

Purpose

Evaluate a code change for correctness, safety, compatibility, and maintainability.

Prioritize defects with real impact over subjective style preferences.

Do not modify the code unless the user explicitly requests corrections.

Review workflow

1. Establish the review scope

Determine what must be reviewed:

  • current working tree changes;
  • staged changes;
  • a commit;
  • a branch comparison;
  • a pull request;
  • specific files;
  • a supplied patch or diff.

Identify the intended behavior of the change before judging its implementation.

Do not expand the review into unrelated parts of the repository without a concrete reason.

2. Inspect repository guidance

Before reviewing:

  • read applicable AGENTS.md files;
  • inspect relevant project documentation;
  • identify language, framework, runtime, and package manager;
  • inspect testing, linting, formatting, and build conventions;
  • understand established architectural patterns.

Review the change against the repository's actual conventions, not generic preferences.

3. Understand the change

Determine:

  • what behavior is being added or changed;
  • which modules and contracts are affected;
  • what assumptions the implementation makes;
  • what data enters and leaves the changed code;
  • whether persistence, authentication, authorization, concurrency, or external integrations are involved.

Read enough surrounding code to understand the changed behavior, but avoid scanning the entire repository.

4. Review functional correctness

Check for:

  • incorrect conditions;
  • incomplete branches;
  • wrong return values;
  • broken state transitions;
  • incorrect asynchronous behavior;
  • unhandled errors;
  • improper null or undefined handling;
  • invalid assumptions about data;
  • incorrect ordering;
  • off-by-one errors;
  • unintended side effects;
  • behavior that contradicts the requested change.

Focus first on defects that could produce incorrect results.

5. Review contracts and compatibility

Read the full file on GitHub · 287 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. 2d ago First seen · 287 lines · 60 tokens per session scan A 43a13e643356

Subscribe to this mod's changes

code-review is a skill published in the GitHub repository Arroyo-Gonzalo/codex-devkit (2 stars, last pushed 1mo ago), licensed MIT. It adds 60 tokens to every session and 1,375 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 2026-08-31.

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