Code Review plugin for Claude Code: review, how it works and whether it is worth it (2026)

What you get in one minute#

The code-review plugin is one prompt file that makes Claude review a GitHub pull request with five parallel reviewers and post one comment; it is a niche tool now, because Claude Code has a built-in /code-review that does more.

Logo: the official Claude Code logo from Anthropic's press kit (anthropic.com/press-kit)

The marketplace page shows 438,525 installs (October 2026).

What it does#

You give it a pull request, and it decides whether to review it, checks it against your CLAUDE.md files and posts the findings as one comment. It adds one slash command and nothing else.

• 1 command: /code-review:code-review <PR number or URL> (the namespaced name; a bare /code-review is the built-in skill).
• 0 skills, 0 agents, 0 hooks, 0 MCP servers. The "agents" are sub-agents the prompt asks Claude to start.
• Needs the GitHub CLI gh, logged in.
• Skips closed, draft, trivial and already-reviewed pull requests.

How it works in the background#

One 92-line prompt is the whole program: Claude follows its steps and launches cheap and strong sub-agents in turn. The picture follows one review.

• Step 5 reviewers: CLAUDE.md compliance, a shallow bug scan, git blame history, comments on earlier PRs, and code comments.
• Nothing forces the steps. Claude may skip some; see the complaints below.

Under the hood: dissection#

The plugin is four files and no code that runs by itself; the only logic is a Markdown prompt.

The file tree#

code-review/
├── .claude-plugin/
│   └── plugin.json            name, description, author (no version)
├── commands/
│   └── code-review.md         the prompt: steps, rubric, comment format
├── LICENSE                    Apache 2.0
└── README.md                  says 4 agents; the prompt has 5

What each file is#

Key excerpts#

commands/code-review.md, the permission line:

allowed-tools: Bash(gh issue view:*), Bash(gh search:*), Bash(gh issue list:*),
Bash(gh pr comment:*), Bash(gh pr diff:*), Bash(gh pr view:*), Bash(gh pr list:*)

The same file, the filter step:

6. Filter out any issues with a score less than 80.
   If there are no issues that meet this criteria, do not proceed.

Disk and network#

• Writes: nothing locally. The prompt posts one comment with gh pr comment.
• Network: only GitHub through gh, plus the model calls.
• Needs: gh and a GitHub remote. Two other copies exist (anthropics/claude-plugins-public is identical; anthropics/claude-code has a newer four-agent variant with --comment).

Chart: file sizes from the GitHub tree at commit 41f619d, 27 October 2026. The prompt is the only part Claude reads.

What users say#

25 GitHub issues read: 0 praise, 3 mixed, 22 complaints, but the split is skewed. Issue trackers collect problems, and many reports come from unattended CI runs. Reddit was not read. The Hacker News comments we found were about the built-in command or Anthropic's managed service, so they are not counted.

Chart: our count of the 25 reports, October 2026. Not a satisfaction rate.

Chart: themes of the 22 complaints, labelled by DIY Lab Hub, October 2026.

Pros: why it is useful#

It is a small, readable recipe for a multi-agent PR review, and it respects your CLAUDE.md.

• Cheap gatekeeping: Haiku does the eligibility and scoring steps; Sonnet does the review.
• Fewer nitpicks: the prompt lists false positives to drop (linter issues, old code, style).
• Traceable output: every finding links to code with a full SHA.
• Easy to inspect and fork: 92 lines, Apache 2.0.

Cons: why it is not useful#

It overlaps with a stronger built-in command, and its own prompt has known holes.

• Built-in wins on features: /code-review runs on any plan, reviews local branches, takes effort levels, --fix and --comment.
• Threshold maths: the rubric scores 0, 25, 50, 75, 100 but the filter drops below 80, so a 75 never shows (issue, May 2026).
• Re-reviews never happen: "already reviewed" has no commit check (issue, September 2026).
• Silent failures in CI and a "version unknown" update notice.

Should you consider it? When it is useful#

Consider it for one case only: you want a CLAUDE.md-aware review posted to a GitHub PR from the terminal or a workflow. Otherwise use the built-in /code-review.

Install and check it#

You install it from Anthropic's official marketplace with one command, and gh must be logged in.

Linux#

Install gh from cli.github.com and run gh auth login. Then, inside Claude Code:

/plugin install code-review@claude-plugins-official

Or from your shell:

claude plugin install code-review@claude-plugins-official

Windows (PowerShell)#

winget install --id GitHub.cli
gh auth login
claude plugin install code-review@claude-plugins-official

Mac (Terminal)#

brew install gh
gh auth login
claude plugin install code-review@claude-plugins-official

Check it worked#

claude plugin list
claude plugin details code-review

Type / and look for /code-review:code-review. Run it on a small test PR first.

Things to keep in mind#

• Security. It runs no hooks or scripts, but the command pre-approves gh pr comment with any flags, and it posts publicly on your PR.
• Cost. Each run starts at least 9 sub-agents plus one scorer per issue; watch /usage.
• Updates. Auto-update is on for the official marketplace; the "unknown" version can repeat "plugin updated" notices.
• Your repository: it only reads and comments, but one reporter saw Claude stash work and switch branch (issue, September 2026); commit first.
• Organisations can restrict marketplaces.

Troubleshooting#

FAQ#

Is this the same as /code-review? No. The bare /code-review is a built-in skill; the plugin is /code-review:code-review.

Can I change the 80 threshold? Only by editing the command file in the plugin cache, and updates overwrite it.

Does it work with GitLab? Not in this copy; the built-in --comment supports GitLab merge requests.

Sources#

• anthropics/claude-plugins-official: plugins/code-review/, marketplace entry, commit 41f619d (October 2026).
• Code Review on the Claude marketplace: 438,525 installs (October 2026).
• Claude Code docs: Review locally with /code-review, Code Review service, Install and manage plugins, what's new, week 21 (October 2026).
• User reports: official-repo issues 5596, 6026, 1700, 1852, 4853, 5910; claude-code issues 91167, 85275, 38964, 33357 (2026).

Not run by DIY Lab Hub: we read the files and docs but did not install the plugin on a test machine.

Checked against the official docs on 2026-10-27