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Skill · .md packageTrail of Bits/10 trustVerified

harness-writing

Designs and improves fuzzing harnesses for C/C++ and Rust.

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About

Designs and improves fuzzing harnesses for C/C++ and Rust. Covers mapping raw bytes onto a target API, generating structured inputs, avoiding non-determinism and false crashes, and deciding what to fuzz together. Use when writing a first LLVMFuzzerTestOneInput or fuzz_target! harness, when a campaign finds nothing or reports crashes that will not reproduce, or when the target API needs structured rather than raw input.

What it can do

  • Designs and improves fuzzing harnesses for C/C++ and Rust. Covers mapping raw bytes onto a target API, generating structured inputs, avoiding non-determinism and false crashes, and deciding what to fuzz together. Use when writing a first LLVMFuzzerTestOneInput or fuzz_target! harness, when a campaign finds nothing or reports crashes that will not reproduce, or when the target API needs structured rather than raw input.

Setup

  1. Install: npx skills add trailofbits/skills --all
  2. The skill auto-loads when relevant, or invoke it by name in your agent.

Prerequisites

A compatible AI coding agent (Claude Code, Cursor, etc.).

Use cases

codedesignsecuritywriting

Works with

Claude CodeAny agent (.md)

Trust score — 9/10

/10 trustVerified

Trail of Bits is a top-tier security research firm; their skills are professional-grade auditing and fuzzing playbooks used by their own engineers. Open source.

Sources

Every fact above was checked against these sources. Where a claim comes from the provider and couldn't be independently verified, the text says so.