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PreToolUse

PreToolUse is a hook for Claude Code from Cotal-AI/Cotal. Its token cost is not measured, scanned A, a copy of SessionStart, Apache-2.0.

A pre-tool hook is a script that runs before the coding agent uses a tool. This configuration runs a Node.js file supplied by the plugin.

In plain words
What is it for?
Running a Node.js hook before tool calls, such as for validation or setup when the plugin provides that behavior.
Why use it?
It lets the plugin check or prepare each tool action before it happens. The description does not say what checks the script performs.

Hook for Claude Code

Written for Claude Code: ${CLAUDE_PLUGIN_ROOT} variable.

Runs only inside its plugin — its command needs a path that Claude Code sets for a plugin’s own hooks and for nothing else. Install the plugin, not this.

Part of the cotal plugin — 7 hooks, 1 MCP server shipped together

One of 7 entries in hooks.json — they are configured in one file and arrive together.

not rated 258 +3 today A scan tokens not measured copy · 58% Apache-2.0
View the source file Cotal-AI/Cotal cotal.ai
Install

Getting it into your agent

This one installs as part of its plugin. Adding the marketplace and installing the plugin brings it with everything else the plugin ships.

Claude Code
/plugin marketplace add Cotal-AI/Cotal
Claude Code
/plugin install cotal

Made for: Claude Code.

Or install cotal, the plugin that ships this one along with the rest of its 7 hooks, 1 MCP server.

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/cotal-ai/cotal/pre-tool-use.svg)](https://agentmods.dev/hooks/cotal-ai/cotal/pre-tool-use)
Your own site
<a href="https://agentmods.dev/hooks/cotal-ai/cotal/pre-tool-use"><img src="https://agentmods.dev/badge/hooks/cotal-ai/cotal/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 58% copy Near-identical to another mod 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 6d 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.

Origin

This is a copy

58% identical to SessionStart — 7 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.

extensions/connector-claude-code/hooks/hooks.json · 12 lines

What it actually says

{
  "PreToolUse": [
    {
      "hooks": [
        {
          "type": "command",
          "command": "node \"${CLAUDE_PLUGIN_ROOT}/dist/hook.cjs\""
        }
      ]
    }
  ]
}
Same file

What else hooks.json configures

This page is one entry in a file that holds 7. 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. 6d ago First seen · 12 lines scan A 995d8a06a20d

Subscribe to this mod's changes

PreToolUse is a hook published in the GitHub repository Cotal-AI/Cotal (258 stars, last pushed today), licensed Apache-2.0. 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. It is 58% identical to SessionStart, differing in 7 lines, and is treated as a copy.

a2aagent-orchestrationaiai-agentsinfrastructureprotocol
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