code-review

Reviews a git diff against documented coding standards and the originating spec in parallel sub-agents.

Updated Sep 18, 2026
One-click install
npx skills add https://github.com/fern-works/greenline --skill code-review-fern-works
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: code-review
Source: https://github.com/fern-works/greenline/tree/main/corpus/upstream/mattpocock-skills/3cca18b368ae95cdbdebbff572ccafa662551015/code-review
Command: npx skills add https://github.com/fern-works/greenline --skill code-review-fern-works

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve? Reviewing a branch or PR requires checking two separate questions at once: does the code follow the repo's standards, and does it actually implement what the issue asked for. Mixing both in one review lets one axis mask the other, and doing it manually against a large diff is slow and inconsistent. ## Core Features & Use Cases - Two-axis review: Runs a Standards review (repo-documented rules plus a fixed Fowler code-smell baseline) and a Spec review (requirements coverage, scope creep, wrong implementations) as parallel sub-agents, then reports them side by side. - Fixed-point diffing: Reviews the changes since any commit, branch, tag, or merge-base using git diff <fixed-point>...HEAD, with early validation that the ref resolves and the diff is non-empty. - Spec source discovery: Locates the originating spec from issue references in commit messages, a user-supplied path, or spec files under docs/, specs/, or .scratch/. - Use Case: Before merging a feature branch, ask for a review since main and receive separate ## Standards and ## Spec reports, each citing the violated rule or spec line, plus a per-axis summary. ## Quick Start Ask the agent to review this branch since main using the code-review skill and report standards and spec findings separately.

Frequently Asked Questions about code-review

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I review all changes on a branch since main?▼

Provide a fixed point such as main, a tag, or a commit SHA, and the review compares it against HEAD using a three-dot git diff from the merge-base. The ref is validated and the diff confirmed non-empty before the review starts.

How does the code review check against coding standards?▼

The Standards axis reads documented standards files like CODING_STANDARDS.md or CONTRIBUTING.md, then applies a fixed baseline of Fowler code smells such as Duplicated Code and Feature Envy. Documented repo standards always override the baseline.

Can it review code against the original issue or spec?▼

Yes, the Spec axis locates the originating spec from issue references in commit messages, a user-provided path, or files under docs/, specs/, or .scratch/. It reports missing requirements, scope creep, and incorrect implementations, quoting the spec line for each finding.

What happens if there is no spec for the changes?▼

If no spec is found and the user confirms none exists, the Spec sub-agent is skipped and the final report notes that no spec was available. The Standards review still runs normally.

Why are standards and spec findings reported separately?▼

A change can pass one axis and fail the other, such as clean code implementing the wrong thing. Keeping the reports separate under distinct headings prevents one axis from masking the other and avoids reranking findings across axes.