agentmods.dev

PreToolUse

PreToolUse is a hook for coding agents from es6kr/skills. Its token cost is not measured, scanned A, original, MIT.

Checks that run before the agent uses tools such as Bash, file editing, skills, workflows, or other agents. The listed scripts inspect commands and block several risky or disallowed actions.

In plain words
What is it for?
Use it to review Bash commands, block compound commands, protect production branches, prevent malformed workflows, and enforce project rules before tool use.
Why use it?
They add guardrails before actions happen, helping prevent unsafe shell commands, repeated triggers, unsuitable branch operations, and other workflow violations.

Hook

Part of the es6kr plugin — 32 skills, 5 hooks shipped together

One of 5 entries in hooks.json — they are configured in one file and arrive together.

2 3d ago A scan tokens not measured original MIT
View the source file es6kr/skills
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/es6kr/skills/pre-tool-use
Clone the repo
git clone --depth 1 https://github.com/es6kr/skills

Or install es6kr, the plugin that ships this one along with the rest of its 32 skills, 5 hooks.

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 · 217 lines

How it starts

The opening of the file, as written. The whole thing — 217 lines — stays where its author put it; the contents beside it link to each section on GitHub.

{
  "PreToolUse": [
    {
      "matcher": "Bash",
      "hooks": [
        {
          "type": "command",
          "command": "${CLAUDE_PLUGIN_ROOT}/skills/hook-kit/resources/bash-guard.py"
        },
        {
          "type": "command",
          "command": "${CLAUDE_PLUGIN_ROOT}/skills/hook-kit/resources/block-compound-commands.sh"
        },
        {
          "type": "command",
          "command": "python3 ${CLAUDE_PLUGIN_ROOT}/skills/hook-kit/resources/block-copilot-rate-limit.sh"
        },
        {
          "type": "command",
          "command": "bash ${CLAUDE_PLUGIN_ROOT}/skills/hook-kit/resources/block-squash-subject-without-pr.sh"
        },
        {
          "type": "command",
          "command": "bash ${CLAUDE_PLUGIN_ROOT}/skills/hook-kit/resources/block-bot-re-trigger.sh"
        },
        {
          "type": "command",
          "command": "bash ${CLAUDE_PLUGIN_ROOT}/skills/hook-kit/resources/block-long-silent-watcher.sh"
        },
        {
          "type": "command",
          "command": "bash ${CLAUDE_PLUGIN_ROOT}/skills/hook-kit/resources/block-prod-branch-autonomous-ops.sh"
        },
        {
          "type": "command",
          "command": "bash ${CLAUDE_PLUGIN_ROOT}/skills/hook-kit/resources/block-delegation-in-github-body.sh"
        },
        {
          "type": "command",
          "command": "bash ${CLAUDE_PLUGIN_ROOT}/skills/hook-kit/resources/block-taskcreate-error-unretried.sh"
        },
        {
          "type": "command",
          "command": "bash ${CLAUDE_PLUGIN_ROOT}/skills/consolidate/resources/block-noncompliant-review-comment.sh"
        },
        {
          "type": "command",
          "command": "bash ${CLAUDE_PLUGIN_ROOT}/skills/consolidate/resources/block-summary-fabricated-claims.sh"
        }
      ]
    },
    {
      "matcher": "Edit",
      "hooks": [
        {
          "type": "command",
          "command": "node ${CLAUDE_PLUGIN_ROOT}/skills/fix-plan/resources/block-direct-checklist-edit.js"

Read the full file on GitHub · 217 lines

Same file

What else hooks.json configures

This page is one entry in a file that holds 5. 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 · 217 lines scan A ad37c18236ee

Subscribe to this mod's changes

PreToolUse is a hook published in the GitHub repository es6kr/skills (2 stars, last pushed 3d 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.

Security
Related

Other hooks, from other repositories

PostToolUse

Runs after a tool call finishes for Write and Edit tool calls, executing format_and_lint.sh. From supabase/supabase.

supabase/supabase · not measured

SessionStart

Runs when a session starts, executing on-start.js via node. From google-gemini/gemini-cli.

google-gemini/gemini-cli · not measured

SessionStart

Runs when a session starts on startup, executing install_pkgs.sh. From supabase/supabase.

supabase/supabase · not measured

PreToolUse

Runs before the agent uses a tool for Bash tool calls, running an inline shell check. From apache/superset.

apache/superset · not measured

PreToolUse

Runs before the agent uses a tool, executing pre-write.sh and pre-bash.sh (2 commands). From anthropics/claude-cookbooks.

anthropics/claude-cookbooks · not measured

SessionStart

Runs when a session starts, executing session-start.sh. From anthropics/claude-cookbooks.

anthropics/claude-cookbooks · not measured