lean-review

A review focused only on code that may be more complicated than needed. It identifies candidates for deletion, standard-library or built-in replacements, and shorter equivalent code.

In plain words
What is it for?
Reviewing a diff or selected files for dead code, unused flexibility, one-use abstractions, avoidable dependencies, and other possible reductions without editing them.
Why use it?
It helps separate unnecessary complexity from real correctness, security, or performance problems, which belong in a normal code review.

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/ezbuilder/code-brain/lean-review
Any agent
npx skills add ezBuilder/code-brain --skill lean-review
Clone the repo
git clone --depth 1 https://github.com/ezBuilder/code-brain

Made for: Claude Code, Codex.

Per session 22 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 344 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 $0.00022 $0.00344
Opus 5 $0.00011 $0.00172
Sonnet 5 $0.00004 $0.00069
Haiku 4.5 $0.00002 $0.00034

Measured 2d ago against content hash b1fe56b63cd7, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

lean-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.

kits/global-agent-kit/.claude/skills/lean-review/SKILL.md · 33 lines

What it actually says

현재 diff나 지정 범위를 correctness/security가 아니라 과설계 관점으로만 검토한다.

찾을 항목:

  • delete: 죽은 코드, 투기적 기능, 사용되지 않는 유연성
  • stdlib: 표준 라이브러리로 대체 가능한 직접 구현
  • native: 플랫폼/DB/CSS/브라우저 기본 기능으로 대체 가능한 코드나 의존성
  • yagni: 구현체 하나뿐인 abstraction/factory/wrapper, 설정값 하나뿐인 config
  • shrink: 같은 동작을 더 짧게 표현할 수 있는 코드

보고 형식:

<file>:L<line>: <delete|stdlib|native|yagni|shrink>: <cut>. <replacement>.

끝에 net: -<N> lines possible.을 적는다. 줄일 것이 없으면 Lean already. Ship.만 적는다.

범위:

  • 수정하지 않고 보고만 한다.
  • correctness, security, performance 이슈는 일반 code-review로 넘긴다.
  • 최소 smoke/self-check는 과설계로 보지 않는다.

KEEP(과설계로 보지 않는다 — 삭제 후보로 올리지 말 것):

  • 경계 입력 검증, I/O·외부호출 예외 처리, 데이터 손실/유실 방지 코드
  • 비자명한 이유를 설명하는 WHY 주석
  • 접근성·보안·검증 로직, 명시적 요구사항
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 · 33 lines · 22 tokens per session scan A b1fe56b63cd7

Subscribe to this mod's changes

lean-review is a skill published in the GitHub repository ezBuilder/code-brain (11 stars, last pushed 2d ago), licensed Apache-2.0. It adds 22 tokens to every session and 344 once invoked, about $0.0001 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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