Systematic code maturity assessment using Trail of Bits' 9-category framework. Analyzes codebase for arithmetic safety, auditing practices, access controls, complexity, decentralization, documentation, MEV risks, low-level code, and testing. Produces professional scorecard with evidence-based ratings and actionable recommendations.
differential-review
differential-review is an open-source testing skill for Claude Code and compatible agents, published by trailofbits. Its author describes it as: “Performs security-focused differential review of code changes (PRs, commits, diffs). Adapts analysis depth to codebase size, uses git history for context, calculates blast radius, checks test coverage, and generates c…”. The project has 6.6k stars on GitHub and is available under the CC-BY-SA-4.0 license. Add it to your setup with `/plugin marketplace add trailofbits/skills`.
What differential-review does
Security-focused code review for PRs, commits, and diffs.
Installation
Add differential-review to your agent with:
/plugin marketplace add trailofbits/skillsAlways review a skill's source before installing it. This command comes from the skill's public repository; the linked repo is the source of truth for exact setup steps.
What's inside
The SKILL.md for differential-review is organised into these sections:
- Core Principles
- Rationalizations (Do Not Skip)
- Quick Reference
- Codebase Size Strategy
- Risk Level Triggers
- Workflow Overview
- Decision Tree
- Agents
- Quality Checklist
- Integration
- Example Usage
- Quick Triage (Small PR)
When to use it
Reach for differential-review when you want testing help from your agent without writing the same instructions every session. Load the skill and the agent picks it up automatically for relevant tasks.
Strengths
- Clear CC-BY-SA-4.0 license — safe to read and adapt
- Ships in trailofbits/skills, an established project with 6,646 GitHub stars
- Actively maintained (recent commits)
Topics
Frequently asked questions
- What does differential-review do?
- Performs security-focused differential review of code changes (PRs, commits, diffs). Adapts analysis depth to codebase size, uses git history for context, calculates blast radius, checks test coverage, and generates comprehensive markdown reports. Automatically detects and prevents security regressions.
- How do I install differential-review?
- Run /plugin marketplace add trailofbits/skills in your agent, then reload your skills. Review the source at https://github.com/trailofbits/skills before installing.
- Is differential-review free to use?
- Yes. differential-review is free and open source under the CC-BY-SA-4.0 license, so you can read, run, and adapt it within that license's terms.
- Where does differential-review come from?
- differential-review ships inside trailofbits/skills, a repository that contains 41 catalogued skills in total. The repository's 6,646 GitHub stars apply to that whole collection, not to this skill on its own.
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