PreToolUse

PreToolUse is a hook for Claude Code from gpt-cmdr/ras-commander. Its token cost is not measured, scanned A, a copy of SessionStart, MIT.

A pre-tool hook that runs a Python dispatcher before the coding agent uses a tool. A hook is an automatic action triggered by a specific event.

In plain words
What is it for?
Use it to connect the agent’s tool calls to the repository’s hook-dispatch script and its associated pre-use handling.
Why use it?
It lets the repository check or handle tool-use events consistently before they happen, without relying on the agent to remember each time.

Hook for Claude Code

One of 4 entries in settings.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/gpt-cmdr/ras-commander/pre-tool-use
Clone the repo
git clone --depth 1 https://github.com/gpt-cmdr/ras-commander

Made for: Claude Code.

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/gpt-cmdr/ras-commander/pre-tool-use.svg)](https://agentmods.dev/hooks/gpt-cmdr/ras-commander/pre-tool-use)
Your own site
<a href="https://agentmods.dev/hooks/gpt-cmdr/ras-commander/pre-tool-use"><img src="https://agentmods.dev/badge/hooks/gpt-cmdr/ras-commander/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 1 finding. Scan, not verified.
Origin 89% copy Near-identical to another mod in the catalogue.
Security

Grade A, and why

PreToolUse scanned grade A with 1 finding 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 5d 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.

Runs shell commandslowCapability

Expected in a hook, worth knowing in a rule or an instructions file.

"command": "python -c \"import pathlib,subprocess,runpy,sys; root=subprocess.check_output(['git','rev-parse','--show-toplevel'], text=True).strip(); sys.argv=['hook_dispatch.py']+sys.argv[1:]; runpy.run_path(str(pathlib.
Origin

This is a copy

89% identical to SessionStart — 4 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.claude/settings.json · 14 lines

What it actually says

{
  "PreToolUse": [
    {
      "matcher": "*",
      "hooks": [
        {
          "type": "command",
          "command": "python -c \"import pathlib,subprocess,runpy,sys; root=subprocess.check_output(['git','rev-parse','--show-toplevel'], text=True).strip(); sys.argv=['hook_dispatch.py']+sys.argv[1:]; runpy.run_path(str(pathlib.Path(root,'scripts','agent_hooks','hook_dispatch.py')), run_name='__main__')\" PreToolUse",
          "timeout": 10
        }
      ]
    }
  ]
}
Same file

What else settings.json configures

This page is one entry in a file that holds 4. 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. 5d ago First seen · 14 lines scan A 33a04a9f3f8e

Subscribe to this mod's changes

PreToolUse is a hook published in the GitHub repository gpt-cmdr/ras-commander (79 stars, last pushed today), 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 1 finding (runs shell commands). It is 89% identical to SessionStart, differing in 4 lines, and is treated as a copy.