PreToolUse

PreToolUse is a hook for coding agents from VersoXBT/claude-initial-setup. Its token cost is not measured, scanned A, original, MIT.

Rules that run before selected shell commands and display reminders for potentially risky or long-running actions.

In plain words
What is it for?
Use them before starting development servers, pushing code, or installing packages. The listed rules suggest using a persistent session, checking package legitimacy, and reviewing changes.
Why use it?
They prompt the developer to consider persistence, package safety, and review before commands that can affect the project or repository.

Hook

Part of the claude-initial-setup plugin — 24 skills, 15 commands, 14 agents, 2 hooks shipped together

One of 2 entries in hooks.json — they are configured in one file and arrive together.

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 hooks/versoxbt/claude-initial-setup/pre-tool-use
Clone the repo
git clone --depth 1 https://github.com/VersoXBT/claude-initial-setup

Or install claude-initial-setup, the plugin that ships this one along with the rest of its 24 skills, 15 commands, 14 agents, 2 hooks.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for PreToolUse

README.md
[![agentmods](https://agentmods.dev/badge/hooks/versoxbt/claude-initial-setup/pre-tool-use.svg)](https://agentmods.dev/hooks/versoxbt/claude-initial-setup/pre-tool-use)
Your own site
<a href="https://agentmods.dev/hooks/versoxbt/claude-initial-setup/pre-tool-use"><img src="https://agentmods.dev/badge/hooks/versoxbt/claude-initial-setup/pre-tool-use.svg" alt="Measured on agentmods" height="20"></a>
Per session not measured What this adds to a session before it is invoked.
When invoked not measured Not applicable: nothing here is loaded into a session.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Security

Grade A, and why

PreToolUse 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 3d ago.

A static scan of the commands this hook runs, not an audit. A hook is shell that executes on your machine at the event it names, which is why every command in it is printed with what was found.

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.

hooks/hooks.json · 34 lines

What it actually says

{
  "PreToolUse": [
    {
      "matcher": "tool == \"Bash\" && tool_input.command matches \"(npm run dev|pnpm( run)? dev|yarn dev|bun run dev)\"",
      "hooks": [
        {
          "type": "command",
          "command": "echo '[Hook] Consider running dev servers in tmux for session persistence' >&2"
        }
      ],
      "description": "Remind to use tmux for dev servers"
    },
    {
      "matcher": "tool == \"Bash\" && tool_input.command matches \"git push\"",
      "hooks": [
        {
          "type": "command",
          "command": "echo '[Hook] Review changes before pushing. Run git diff and git status first.' >&2"
        }
      ],
      "description": "Reminder before git push"
    },
    {
      "matcher": "tool == \"Bash\" && tool_input.command matches \"(npm|pnpm|yarn|bun) (install|add)\"",
      "hooks": [
        {
          "type": "command",
          "command": "echo '[Hook] Verify package legitimacy before installing. Check for typosquatting.' >&2"
        }
      ],
      "description": "Security reminder before installing packages"
    }
  ]
}
Same file

What else hooks.json configures

This page is one entry in a file that holds 2. Installing the file brings all of them; each is measured and scanned on its own page.

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. 3d ago First seen · 34 lines scan A 5f0a6d96c5f7

Subscribe to this mod's changes

PreToolUse is a hook published in the GitHub repository VersoXBT/claude-initial-setup (4 stars, last pushed 3mo ago), licensed MIT. Its token cost is not measured: a hook is shell that never enters the context. 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 2026-08-31.