code-review

A pre-pull-request code review process focused on changed lines. A pull request is a request for teammates to review and merge a set of code changes.

In plain words
What is it for?
Use it to identify the right changes to inspect, give priority-based feedback, and fix review findings one at a time before submitting a pull request.
Why use it?
It helps catch correctness, product, accessibility, testing, maintainability, and project-convention problems before they reach a pull request.

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/block/berd/code-review
Any agent
npx skills add block/berd --skill code-review
Clone the repo
git clone --depth 1 https://github.com/block/berd

Made for: Claude Code, Codex.

Per session 61 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 4,389 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 $0.00061 $0.04389
Opus 5 $0.00030 $0.02194
Sonnet 5 $0.00012 $0.00878
Haiku 4.5 $0.00006 $0.00439

Measured 2d ago against content hash bc53ac99d818, 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.

.agents/skills/code-review/SKILL.md · 314 lines

How it starts

The opening of the file, as written. The whole thing — 314 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Pre-PR Code Review

You are a senior engineer conducting a thorough code review. Review only the lines that changed in this branch and provide actionable feedback on correctness, product behavior, maintainability, accessibility, tests, and project conventions. Do not flag issues in unchanged code, but follow changed code paths into surrounding modules when needed to verify a changed-line issue.

Determine Files To Review

Before starting the review, identify which files to review by checking:

  1. Resolve the review base branch:

    • Prefer the branch's upstream merge base when one exists
    • Otherwise, discover the default branch with git remote show origin
    • Fall back to origin/main only if the repo does not expose a default branch
  2. Run git commands to check both:

    • Committed changes: git diff --name-only <base>...HEAD
    • Unstaged/staged changes: git status --short
  3. Ask the user which set to review if both exist:

    • If there are both committed changes and unstaged/staged changes, ask: "I see both committed changes and unstaged/staged changes. Which would you like me to review?"
      • Option A: Committed changes in this branch (compare against the review base)
      • Option B: Current unstaged/staged changes
      • Option C: Both
  4. Proceed automatically if only one set exists:

    • If only committed changes exist, review those
    • If only unstaged/staged changes exist, review those
    • If neither exists, tell the user there are no changes to review
  5. Get the file list based on the user's choice:

    • For committed changes: use git diff --name-only <base>...HEAD
    • For unstaged/staged: use git diff --name-only and git diff --cached --name-only
    • Filter to only include files that still exist, unless deleted files are relevant to the review

Only proceed with the review once you have the specific list of files to review.

Review Passes

Run these as passes, then consolidate findings before presenting them. A finding should appear once, even if multiple sections support it.

Read the full file on GitHub · 314 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 · 314 lines · 61 tokens per session scan A bc53ac99d818

Subscribe to this mod's changes

code-review is a skill published in the GitHub repository block/berd (828 stars, last pushed 2d ago), licensed Apache-2.0. It adds 61 tokens to every session and 4,389 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.

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