code-review

name	Code Review
description	Use when reviewing a diff or pull request — find correctness bugs first, then reuse/simplification cleanups, and report each finding with a concrete failure scenario ranked by severity.
version	1.0.0

Code Review

A review's job is to catch what tests and the type checker won't. Read the diff for correctness first; treat style and cleanup as secondary.

Scope

• The diff is the scope. But read the enclosing function of each hunk — a change can re-expose or fail to fix a bug in nearby lines.
• Check callers and callees of anything the diff changes: a new precondition, a changed return shape, or a new thrown error can break a call site the diff doesn't touch.

Look for, in order

1. Correctness — the highest-value findings:
   • Inverted/wrong conditions, off-by-one, wrong variable (copy-paste).
   • Null/undefined access, missing await, unhandled promise rejection.
   • Falsy-zero / empty-string bugs (if (!count) when 0 is valid).
   • Removed guards or validation with nothing re-establishing them.
   • Error swallowed in a catch that should propagate.
2. Cleanup — only after correctness:
   • Reinvented helpers that already exist in the codebase.
   • Duplicated logic, dead code, needless complexity, redundant state.
   • Wasted work: repeated I/O, sequential calls that could be parallel.
3. Conventions — clear violations of the repo's stated rules, quoted.

Reporting a finding

Every finding needs a concrete failure scenario, not a vibe:

src/foo.ts:42 — parseId returns undefined for empty input, but the caller indexes into it → TypeError when the list is empty.

• Rank most-severe first. A correctness bug always outranks a cleanup.
• Say how sure you are. If you can't name inputs that break it, mark it as "possible" rather than asserting a bug.
• Prefer "here's the failing case" over "consider refactoring."

Restraint

Don't flag style the linter already enforces, don't rewrite to personal taste, and don't invent requirements. A short list of real bugs beats a long list of nitpicks. See references/review-checklist.md.