New to Claude Skills? Learn how to install them →

trailofbits on GitHub

Audit Prep Assistant

Free

Streamline your security review preparation process.

Get this skill

Free · Opens the source repo

What Audit Prep Assistant does

The Audit Prep Assistant is designed to help developers and teams prepare their codebases for security reviews using the comprehensive checklist provided by Trail of Bits. This tool focuses on making the audit process smoother and more effective by guiding users through a structured preparation workflow. It is particularly beneficial for teams looking to enhance their security posture prior to an audit, ensuring that they address potential vulnerabilities and present a well-documented codebase.

The preparation process is divided into several key steps. First, it assists in setting clear review goals by prompting users to define their security objectives and areas of concern. This step is crucial for aligning expectations with the assessment team. Next, the tool runs static analysis on the codebase, helping to identify and fix low-hanging fruit issues while also increasing test coverage and removing dead code. This ensures that the codebase is clean and ready for scrutiny.

In addition to addressing technical debt, the Audit Prep Assistant emphasizes the importance of accessibility and documentation. It helps users create detailed build instructions, document dependencies, and generate essential documentation such as flowcharts and user stories. These outputs not only facilitate the audit process but also improve the overall maintainability of the codebase. The tool adapts to various programming languages, including Solidity, Rust, and Go, making it versatile for different development environments.

Overall, the Audit Prep Assistant is a valuable resource for any development team preparing for a security review. By following its structured approach, teams can ensure they have a thorough understanding of their codebase, address potential issues proactively, and present a well-prepared package for auditors.

When to use it

Use this tool 1-2 weeks before your scheduled security audit to ensure all necessary preparations are completed.

When not to use it

This skill may not be suitable for projects that are not undergoing a security review or for teams that do not require structured preparation.

What you can build with it

Preparing for a Security Audit

Use the Audit Prep Assistant to organize and prepare your codebase thoroughly before an upcoming security audit.

Improving Code Quality

Leverage the tool to identify and resolve static analysis findings, increase test coverage, and remove dead code.

Enhancing Documentation

Utilize the skill to generate comprehensive documentation that aids both the audit process and future development efforts.

How to install Audit Prep Assistant

View source

1. Install with the skills CLI

npx skills add trailofbits/skills/audit-prep-assistant --agent claude-code

2. Or install it manually

Download the skill folder and drop it into ~/.claude/skills/ for all projects, or .claude/skills/ to scope it to one repo. Restart Claude Code so it picks up the new skill.

Anthropic's agentic coding CLI, and the reference implementation of Agent Skills. Drop a skill folder into ~/.claude/skills and Claude Code loads it automatically whenever a task matches the skill's description. Claude Code docs

Inside SKILL.md

Written by trailofbits

Audit Prep Assistant

Purpose

Helps prepare for a security review using Trail of Bits' checklist. A well-prepared codebase makes the review process smoother and more effective.

Use this: 1-2 weeks before your security audit


The Preparation Process

Step 1: Set Review Goals

Helps define what you want from the review:

Key Questions:

  • What's the overall security level you're aiming for?
  • What areas concern you most?
    • Previous audit issues?
    • Complex components?
    • Fragile parts?
  • What's the worst-case scenario for your project?

Documents goals to share with the assessment team.


Step 2: Resolve Easy Issues

Runs static analysis and helps fix low-hanging fruit:

Run Static Analysis:

For Solidity:

slither . --exclude-dependencies

For Rust:

dylint --all

For Go:

golangci-lint run

For Go/Rust/C++:

# CodeQL and Semgrep checks

Then I'll:

  • Triage all findings
  • Help fix easy issues
  • Document accepted risks

Increase Test Coverage:

  • Analyze current coverage
  • Identify untested code
  • Suggest new tests
  • Run full test suite

Remove Dead Code:

  • Find unused functions/variables
  • Identify unused libraries
  • Locate stale features
  • Suggest cleanup

Goal: Clean static analysis report, high test coverage, minimal dead code


Step 3: Ensure Code Accessibility

Helps make code clear and accessible:

Provide Detailed File List:

  • List all files in scope
  • Mark out-of-scope files
  • Explain folder structure
  • Document dependencies

Create Build Instructions:

  • Write step-by-step setup guide
  • Test on fresh environment
  • Document dependencies and versions
  • Verify build succeeds

Freeze Stable Version:

  • Identify commit hash for review
  • Create dedicated branch
  • Tag release version
  • Lock dependencies

Identify Boilerplate:

  • Mark copied/forked code
  • Highlight your modifications
  • Document third-party code
  • Focus review on your code

Step 4: Generate Documentation

Helps create documentation:

Flowcharts and Sequence Diagrams:

  • Map primary workflows
  • Show component relationships
  • Visualize data flow
  • Identify critical paths

User Stories:

  • Define user roles
  • Document use cases
  • Explain interactions
  • Clarify expectations

On-chain/Off-chain Assumptions:

  • Data validation procedures
  • Oracle information
  • Bridge assumptions
  • Trust boundaries

Actors and Privileges:

  • List all actors
  • Document roles
  • Define privileges
  • Map access controls

External Developer Docs:

  • Link docs to code
  • Keep synchronized
  • Explain architecture
  • Document APIs

Function Documentation:

  • System and function invariants
  • Parameter ranges (min/max values)
  • Arithmetic formulas and precision loss
  • Complex logic explanations
  • NatSpec for Solidity

Glossary:

  • Define domain terms
  • Explain acronyms
  • Consistent terminology
  • Business logic concepts

Video Walkthroughs (optional):

  • Complex workflows
  • Areas of concern
  • Architecture overview

How I Work

When invoked, I will:

  1. Help set review goals - Ask about concerns and document them
  2. Run static analysis - Execute appropriate tools for your platform
  3. Analyze test coverage - Identify gaps and suggest improvements
  4. Find dead code - Search for unused code and libraries
  5. Review accessibility - Check build instructions and scope clarity
  6. Generate documentation - Create flowcharts, user stories, glossaries
  7. Create prep checklist - Track what's done and what's remaining

Adapts based on:

  • Your platform (Solidity, Rust, Go, etc.)
  • Available tools
  • Existing documentation
  • Review timeline

Rationalizations (Do Not Skip)

RationalizationWhy It's WrongRequired Action
"README covers setup, no need for detailed build instructions"READMEs assume context auditors don't haveTest build on fresh environment, document every dependency version
"Static analysis already ran, no need to run again"Codebase changed since last runExecute static analysis tools, generate fresh report
"Test coverage looks decent""Looks decent" isn't measured coverageRun coverage tools, identify specific untested code paths
"Not much dead code to worry about"Dead code hides during manual reviewUse automated detection tools to find unused functions/variables
"Architecture is straightforward, no diagrams needed"Text descriptions miss visual patternsGenerate actual flowcharts and sequence diagrams
"Can freeze version right before audit"Last-minute freezing creates rushed handoffIdentify and document commit hash now, create dedicated branch
"Terms are self-explanatory"Domain knowledge isn't universalCreate comprehensive glossary with all domain-specific terms
"I'll do this step later"Steps build on each other - skipping creates gapsComplete all 4 steps sequentially, track progress with checklist

Example Output

When I finish helping you prepare, you'll have concrete deliverables like:

=== AUDIT PREP PACKAGE ===

Project: DeFi DEX Protocol
Audit Date: March 15, 2024
Preparation Status: Complete

---

## REVIEW GOALS DOCUMENT

Security Objectives:
- Verify economic security of liquidity pool swaps
- Validate oracle manipulation resistance
- Assess flash loan attack vectors

Areas of Concern:
1. Complex AMM pricing calculation (src/SwapRouter.sol:89-156)
2. Multi-hop swap routing logic (src/Router.sol)
3. Oracle price aggregation (src/PriceOracle.sol:45-78)

Worst-Case Scenario:
- Flash loan attack drains liquidity pools via oracle manipulation

Questions for Auditors:
- Can the AMM pricing model produce negative slippage under edge cases?
- Is the slippage protection sufficient to prevent sandwich attacks?
- How resilient is the system to temporary oracle failures?

---

## STATIC ANALYSIS REPORT

Slither Scan Results:
✓ High: 0 issues
✓ Medium: 0 issues
⚠ Low: 2 issues (triaged - documented in TRIAGE.md)
ℹ Info: 5 issues (code style, acceptable)

Tool: slither . --exclude-dependencies
Date: March 1, 2024
Status: CLEAN (all critical issues resolved)

---

## TEST COVERAGE REPORT

Overall Coverage: 94%
- Statements: 1,245 / 1,321 (94%)
- Branches: 456 / 498 (92%)
- Functions: 89 / 92 (97%)

Uncovered Areas:
- Emergency pause admin functions (tested manually)
- Governance migration path (one-time use)

Command: forge coverage
Status: EXCELLENT

---

## CODE SCOPE

In-Scope Files (8):
✓ src/SwapRouter.sol (456 lines)
✓ src/LiquidityPool.sol (234 lines)
✓ src/PairFactory.sol (389 lines)
✓ src/PriceOracle.sol (167 lines)
✓ src/LiquidityManager.sol (298 lines)
✓ src/Governance.sol (201 lines)
✓ src/FlashLoan.sol (145 lines)
✓ src/RewardsDistributor.sol (178 lines)

Out-of-Scope:
- lib/ (OpenZeppelin, external dependencies)
- test/ (test contracts)
- scripts/ (deployment scripts)

Total In-Scope: 2,068 lines of Solidity

---

## BUILD INSTRUCTIONS

Prerequisites:
- Foundry 0.2.0+
- Node.js 18+
- Git

Setup:
```bash
git clone https://github.com/project/repo.git
cd repo
git checkout audit-march-2024  # Frozen branch
forge install
forge build
forge test

Verification: ✓ Build succeeds without errors ✓ All 127 tests pass ✓ No warnings from compiler


DOCUMENTATION

Generated Artifacts: ✓ ARCHITECTURE.md - System overview with diagrams ✓ USER_STORIES.md - 12 user interaction flows ✓ GLOSSARY.md - 34 domain terms defined ✓ docs/diagrams/contract-interactions.png ✓ docs/diagrams/swap-flow.png ✓ docs/diagrams/state-machine.png

NatSpec Coverage: 100% of public functions


DEPLOYMENT INFO

Network: Ethereum Mainnet Commit: abc123def456 (audit-march-2024 branch) Deployed Contracts:

  • SwapRouter: 0x1234...
  • PriceOracle: 0x5678... [... etc]

PACKAGE READY FOR AUDIT ✓ Next Step: Share with Trail of Bits assessment team


---

## What You'll Get

**Review Goals Document**:
- Security objectives
- Areas of concern
- Worst-case scenarios
- Questions for auditors

**Clean Codebase**:
- Triaged static analysis (or clean report)
- High test coverage
- No dead code
- Clear scope

**Accessibility Package**:
- File list with scope
- Build instructions
- Frozen commit/branch
- Boilerplate identified

**Documentation Suite**:
- Flowcharts and diagrams
- User stories
- Architecture docs
- Actor/privilege map
- Inline code comments
- Glossary
- Video walkthroughs (if created)

**Audit Prep Checklist**:
- [ ] Review goals documented
- [ ] Static analysis clean/triaged
- [ ] Test coverage >80%
- [ ] Dead code removed
- [ ] Build instructions verified
- [ ] Stable version frozen
- [ ] Flowcharts created
- [ ] User stories documented
- [ ] Assumptions documented
- [ ] Actors/privileges listed
- [ ] Function docs complete
- [ ] Glossary created

---

## Timeline

**2 weeks before audit**:
- Set review goals
- Run static analysis
- Start fixing issues

**1 week before audit**:
- Increase test coverage
- Remove dead code
- Freeze stable version
- Start documentation

**Few days before audit**:
- Complete documentation
- Verify build instructions
- Create final checklist
- Send package to auditors

---

## Ready to Prep

Let me know when you're ready and I'll help you prepare for your security review!

Frequently asked questions about Audit Prep Assistant

Similar skills