bug-hunt

An adversarial code review that uses three isolated agents to search for bugs, challenge reported findings, and judge which issues are real. It can scan a whole project, a path, a file, or the files changed on a Git branch.

In plain words
What is it for?
It is for hunting bugs before a release or review, checking a specific part of a codebase, or examining branch changes compared with a base branch.
Why use it?
It reduces false bug reports by having separate reviewers verify one another's findings. It also focuses the scan on a branch's changed files when needed.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/danpeg/bug-hunt/bug-hunt
Any agent
npx skills add danpeg/bug-hunt --skill bug-hunt
Clone the repo
git clone --depth 1 https://github.com/danpeg/bug-hunt

Made for: Claude Code, Codex.

Per session 69 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 946 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00069 $0.00946
Opus 5 $0.00034 $0.00473
Sonnet 5 $0.00014 $0.00189
Haiku 4.5 $0.00007 $0.00095

Measured 2d ago against content hash 65ccf0b872fd, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

bug-hunt scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

SKILL.md · 89 lines

How it starts

The opening of the file, as written. The whole thing — 89 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Bug Hunt - Adversarial Bug Finding

Run a 3-agent adversarial bug hunt on your codebase. Each agent runs in isolation.

Usage

/bug-hunt              # Scan entire project
/bug-hunt src/         # Scan specific directory
/bug-hunt lib/auth.ts  # Scan specific file
/bug-hunt -b feature-xyz              # Scan files changed in feature-xyz vs main
/bug-hunt -b feature-xyz --base dev   # Scan files changed in feature-xyz vs dev

Target

The raw arguments are: $ARGUMENTS

Parse the arguments as follows:

  1. If arguments contain -b <branch>: this is a branch diff mode.
    • Extract the branch name after -b.
    • If --base <base-branch> is also present, use that as the base branch. Otherwise default to main.
    • Run git diff --name-only <base>...<branch> using the Bash tool to get the list of changed files.
    • If the command fails (e.g. branch not found), report the error to the user and stop.
    • If no files changed, tell the user there are no changes to scan and stop.
    • The scan target is the list of changed files (scan their full contents, not just the diff).
  2. If arguments do NOT contain -b: treat the entire argument string as a path target (file or directory). If empty, scan the current working directory.

Execution Steps

You MUST follow these steps in exact order. Each agent runs as a separate subagent via the Agent tool to ensure context isolation.

Step 1: Parse arguments and resolve target

Follow the rules in the Target section above to determine the scan target. If in branch diff mode, run the git diff command now and collect the file list.

Step 2: Read the prompt files

Read these files using the skill directory variable:

  • ${CLAUDE_SKILL_DIR}/prompts/hunter.md
  • ${CLAUDE_SKILL_DIR}/prompts/skeptic.md
  • ${CLAUDE_SKILL_DIR}/prompts/referee.md

Step 3: Run the Hunter Agent

Launch a general-purpose subagent with the hunter prompt. Include the scan target in the agent's task. If in branch diff mode, pass the explicit file list so the Hunter only scans those files (full contents). The Hunter must use tools (Read, Glob, Grep) to examine the actual code.

Read the full file on GitHub · 89 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 89 lines · 69 tokens per session scan A 65ccf0b872fd

Subscribe to this mod's changes

bug-hunt is a skill published in the GitHub repository danpeg/bug-hunt (144 stars, last pushed 6mo ago), licensed MIT. It adds 69 tokens to every session and 946 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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