Qt C++ Code Review
x-tools-author/x-tools
Read-only review of Qt6 C++ code that combines a deterministic lint script with six parallel analysis agents and reports only high-confidence issues.
Expert code review specializing in simplicity and correctness.
Install Review
$ npx skills add cashew-labs/libretto --skill review -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install cashew-labs/libretto review --agent claude-codeProject scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).
$ git clone --depth 1 https://github.com/cashew-labs/libretto.git skills-src && mkdir -p .claude/skills && cp -r skills-src/.agents/skills/review .claude/skills/review && rm -rf skills-srcUse ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.
Claude Code skills documentation · loads skills from .claude/skills/
Install the "review" agent skill from https://github.com/cashew-labs/libretto/tree/main/.agents/skills/review into .claude/skills/review/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "review", then confirm the skill loads.Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$skill-installer install https://github.com/cashew-labs/libretto/tree/main/.agents/skills/reviewType this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.
$ npx skills add cashew-labs/libretto --skill review -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install cashew-labs/libretto review --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/cashew-labs/libretto.git skills-src && mkdir -p .agents/skills && cp -r skills-src/.agents/skills/review .agents/skills/review && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "review" agent skill from https://github.com/cashew-labs/libretto/tree/main/.agents/skills/review into .agents/skills/review/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "review", then confirm the skill loads.Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add cashew-labs/libretto --skill review -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install cashew-labs/libretto review --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/cashew-labs/libretto.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/.agents/skills/review .cursor/skills/review && rm -rf skills-srcUse ~/.cursor/skills/ instead of .cursor/skills for a personal install.
Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/
Install the "review" agent skill from https://github.com/cashew-labs/libretto/tree/main/.agents/skills/review into .cursor/skills/review/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "review", then confirm the skill loads.Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gemini skills install https://github.com/cashew-labs/libretto.git --path .agents/skills/review--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.
$ npx skills add cashew-labs/libretto --skill review -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install cashew-labs/libretto review --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/cashew-labs/libretto.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/.agents/skills/review .gemini/skills/review && rm -rf skills-srcUse ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.
Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/
Install the "review" agent skill from https://github.com/cashew-labs/libretto/tree/main/.agents/skills/review into .gemini/skills/review/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "review", then confirm the skill loads.Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gh skill install cashew-labs/libretto reviewInstalls for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).
$ npx skills add cashew-labs/libretto --skill review -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/cashew-labs/libretto.git skills-src && mkdir -p .github/skills && cp -r skills-src/.agents/skills/review .github/skills/review && rm -rf skills-srcUse ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.
GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/
Install the "review" agent skill from https://github.com/cashew-labs/libretto/tree/main/.agents/skills/review into .github/skills/review/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "review", then confirm the skill loads.GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add cashew-labs/libretto --skill review -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install cashew-labs/libretto review --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/cashew-labs/libretto.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/.agents/skills/review .opencode/skills/review && rm -rf skills-srcUse ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.
OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/
Install the "review" agent skill from https://github.com/cashew-labs/libretto/tree/main/.agents/skills/review into .opencode/skills/review/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "review", then confirm the skill loads.OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
Facts
- Skill name
review- GitHub stars
- 904
- Token cost
- ~1.4k tokens
- SKILL.md length
- 656 words
- Files
- 1
- Skills in repo
- 21
- Repo updated
- First seen
- Licence
- MIT
At a glance
Expert code review specializing in simplicity and correctness.
- Works in 5 steps: Find all the changes in this branch → Understand the Goals → Review Implementation → …
- Tasks that involve Code quality
- SKILL.md covers Step 1: Find all the changes…, Step 2: Understand the Goals, Step 3: Review Implementation and Step 4: Check for Orphan Edits, plus 2 more sections
- Calls git
What it does
Review is an agent skill from cashew-labs/libretto. Expert code review specializing in simplicity and correctness. Use after completing implementations to ensure code quality.
Its SKILL.md is about 1.4k tokens, which your agent loads only when the skill is triggered. It is a single SKILL.md file with no bundled scripts.
It sits in Development, covering Code quality and Code review. It works with Git. The repository describes itself as: The AI toolkit for building reliable browser automations. The licence is MIT.
When your agent uses it
- Tasks that involve Code quality
- Tasks that involve Code review
Example prompts
- “/review”
Workflow steps
5 steps, taken from the step headings in SKILL.md.
What it can do on your machine
Read from SKILL.md and the folder at commit 41ab782. It shows what the files ask for, not the result of running them.
Tool permissions
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
Runs code
Shell commands in SKILL.md call:
git
From the folder's file list and the shell code blocks in SKILL.md.
Network
No URLs in SKILL.md. Its commands use git, which can reach the network depending on how they are called.
From URLs in SKILL.md, links to its own repository left out.
Credentials
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.
Context cost
Review loads about 1.4k tokens when it runs. Until then it costs about 33 tokens; SKILL.md has 656 words of instructions outside code blocks.
Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.
Safety
Auto-check passed
The automated check found no risky patterns in SKILL.md.
Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.
SKILL.md
The full file from cashew-labs/libretto at commit 41ab782, republished under its MIT licence (© cashew-labs). 656 words, ~1,393 tokens.
Download SKILL.mdSave it as
.claude/skills/review/SKILL.md (or your agent's skills folder).- name
- review
- description
- Expert code review specializing in simplicity and correctness. Use after completing implementations to ensure code quality.
You are an expert code reviewer specializing in evaluating implementations for simplicity and correctness. Your primary mission is to ensure code achieves its specified goals with the absolute minimum necessary complexity - no more, no less.
Your review process follows these strict steps:
- Find all the changes in this branch
- Understand the goals
- Review implementation
- Check for orphan edits
- Structure your response
Step 1: Find all the changes in this branch
Run git diff main..HEAD --name-only to find all the files that changed in this branch and the most recent commit messages via git log main..HEAD.
IMPORTANT: Ignore any lock-file (e.g. pnpm-lock.yaml) changes. They are almost always irrelevant.
Step 2: Understand the Goals
If a spec file has been created in this branch (a .md file in specs/ directory), read it thoroughly first. Use sub-agents if needed to deeply understand complex requirements.
If no spec exists, use a Task to first infer the goals. Prompt the task to look at:
- The actual changes which you can get by iterating over all of the changes in each of the files using
git diff main..HEAD -- <filename> - Comments and documentation
- Function and variable names
- Overall context of modifications
The sub-agent should give you back thorough documentation about what it believes are the goal(s) of the PR. It's vital that it's detailed - this forms the baseline for your entire review.
Step 3: Review Implementation
For each changed file, read both:
- The diff:
git diff main..HEAD -- <filename> - The full file in its current state
The diff shows what changed; the full file provides context for how those changes integrate with surrounding code. You need both to evaluate correctness and simplicity accurately.
Start with the "root changes" first. For each file's changes, ask:
Simplicity Evaluation
- Could this exact goal be achieved with fewer lines of code?
- Are there abstractions that don't provide clear value?
- Would a more direct approach work just as well?
- Are there entire files or functions that could be eliminated?
- Is there duplicated logic that could be consolidated?
- Are there multiple ways to access the same functionality? There should be exactly one canonical way to access any package, command, or symbol
- Are index.ts files being used for re-exports? These create unnecessary indirection - import directly from source files or direct entry points instead
- Is the same concept implemented in multiple places? Consolidate to a single authoritative implementation
Be specific: Instead of "this could be simpler", explain exactly how. Reference specific line numbers and provide concrete alternatives.
Show full SKILL.md (238 more words)Show less
Correctness Evaluation
- Does the implementation actually fulfill each requirement?
- Will this code work in all expected scenarios?
- Are there obvious edge cases that will cause failures?
- Do the changes properly integrate with existing code?
Focus ONLY on actual functionality. You must NOT comment on:
- Performance (unless it would literally break the system)
- Code style or formatting preferences
- Potential future features or extensibility
- Backwards compatibility (unless it breaks core functionality)
- Testing coverage (unless tests themselves are the goal)
IMPORTANT: Ignore any lock-file changes. They are almost always irrelevant.
Step 4: Check for Orphan Edits
Cross-reference your review against the original diff. Any files you haven't examined yet need attention:
- Are these changes necessary for the stated goals?
- Do they represent scope creep?
- Should they be removed from this changeset?
Step 5: Structure Your Response
Your output must follow this exact format:
# PR Review Results
## Spec Analysis
[If spec exists: Concise bullet points of actual requirements]
[If no spec: Clear statement of inferred goals based on the implementation]
## Changed Files
- [filename]: [one-line description of changes]
- [Continue for all modified files]
## Simplicity Assessment
- [Specific evaluation with file paths and line numbers]
- [Example: "The validation in ./src/auth.ts:45-67 could be replaced with a single regex check"]
- [Be precise: always include relative paths and line numbers]
## Correctness Assessment
- [Specific issues with exact locations]
- [Example: "Missing null check in ./api/handlers.js:102 will crash on empty input"]
- [Include line numbers for every issue mentioned]
## Summary
[2-3 sentences only. Overall assessment of whether the implementation achieves its goals appropriately.]
## Required Actions
[List only blocking issues that MUST be fixed. If none exist, explicitly state "None"]
## Suggestions
[List non-blocking improvements and suggestions. If none exist, explicitly state "None"]Critical Reminders
- Your job is to ensure the code does what it needs to do, as simply as possible
- Every piece of feedback must include specific file paths and line numbers
- Suggest removal of code more often than addition
- If something works and meets requirements, don't suggest changes just for preference
- Be direct and actionable - vague feedback wastes everyone's time
- Remember: Perfect is the enemy of good. Focus on what matters.
You are the guardian against complexity creep. Be thorough but pragmatic. Your review should make the code better, not just different.
© cashew-labs, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file
Files
Just SKILL.md in .agents/skills/review of cashew-labs/libretto.
Open the folder on GitHubat commit 41ab782
Compare with similar skills
Review next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.
| Skill | Stars | Used in | Tokens | Auto-check | Licence | Repo updated |
|---|---|---|---|---|---|---|
| Review this skillcashew-labs/libretto | 904 | — | ~1.4k | Automated safety check: Pass | MIT | |
| Qt C++ Code Reviewx-tools-author/x-tools | 1.1k | 2 repos | ~4.3k | Automated safety check: Pass | BSD-3-Clause | |
| Adversarial Reviewer302ai/302-AI-Studio | 132 | 1 repos | ~3k | Automated safety check: Pass | MIT | |
| Feature-Level Code Reviewdataelement/bisheng | 12k | — | ~1k | Automated safety check: Pass | Apache-2.0 | |
| Two-Axis Code Reviewrengwu/wayfinder-maps | 137 | — | ~1.8k | Automated safety check: Pass | MIT | |
| Code Revieweralirezarezvani/claude-code-tresor | 777 | — | ~1.8k | Automated safety check: Pass | MIT |
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Feature-Level Code Review
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Runs a seven-dimension code review on a finished feature, comparing the diff against a base branch and the feature's spec, design and task files.
Two-Axis Code Review
rengwu/wayfinder-maps
Reviews the changes since a commit, branch or tag along two separate axes: the repo's documented coding standards and fidelity to the originating spec or PRD.
Code Reviewer
alirezarezvani/claude-code-tresor
Automatic code quality and best practices analysis. An agent skill from alirezarezvani/claude-code-tresor.
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Review completed implementation batches for spec compliance and code quality.
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Related
Works with
Categories
Questions about Review
What does Review do?
Expert code review specializing in simplicity and correctness. Review is an agent skill from cashew-labs/libretto. Expert code review specializing in simplicity and correctness.
When should I use Review?
Review fits situations like: tasks that involve Code quality; tasks that involve Code review.
How do I install Review in Claude Code?
Run `npx skills add cashew-labs/libretto --skill review -a claude-code`. Or copy the skill folder (.agents/skills/review in cashew-labs/libretto) into .claude/skills/review in your project. Claude Code loads it when a task matches its description.
How do I install Review in Codex?
Run `npx skills add cashew-labs/libretto --skill review -a codex`. Or copy the skill folder (.agents/skills/review in cashew-labs/libretto) into .agents/skills/review in your project. Codex loads it when a task matches its description.
Can I use Review in Cursor, Gemini CLI or GitHub Copilot?
Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add cashew-labs/libretto --skill review -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/review, .gemini/skills/review, .github/skills/review and .opencode/skills/review in your project.
What does Review need to run?
Going by SKILL.md and its folder, Review needs the command-line tools its instructions call (git).
Does Review access the network?
SKILL.md contains no URLs. Its commands use git, which can reach the network depending on how they are called. This is read from the text; nothing was executed.
Is Review safe to install?
Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.
What licence does Review use?
Review is published under the MIT licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.
How many tokens does Review use?
About 1.4k tokens (SKILL.md is roughly 5.6k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full.
What are the alternatives to Review?
Skills that share tags, products or a category with Review: Qt C++ Code Review (x-tools-author/x-tools, 1.1k stars), Adversarial Reviewer (302ai/302-AI-Studio, 132 stars), Feature-Level Code Review (dataelement/bisheng, 12k stars) and Two-Axis Code Review (rengwu/wayfinder-maps, 137 stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
Who maintains Review?
cashew-labs (a GitHub organization) maintains it in cashew-labs/libretto, which has 904 GitHub stars. The repository holds 21 skills in this directory. The repository was last updated on August 21, 2026.
Source: cashew-labs/libretto on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.