agentmods.dev

js2: Hook for Claude Code

.claude/settings.json

PreToolUse is a hook for Claude Code from loopdive/js2. Its token cost is not measured, scanned A, original, Apache-2.0.

A set of checks that run before selected agent tool calls, such as shell commands, Git commits, merges, and agent starts.

In plain words
What is it for?
Use it to enforce repository workflow rules, block bypassed verification, check commit authors, validate merge steps, and protect Git operations.
Why use it?
It catches unsafe working-directory, commit, merge, push, and agent-start conditions before those actions proceed.

Hook for Claude Code

Written for Claude Code: ${CLAUDE_PROJECT_DIR variable.

This is loopdive/js2's own configuration. It tells Claude Code how to work on js2 itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything js2 configures →

One of 9 entries in settings.json upstream. Installing this one merges just its entry into your config; the other 8 are separate, each on its own page.

not rated 67repo changed 1mo ago A scan tokens not measured original Apache-2.0
View source ↗ loopdive/js2 js2.loopdive.com
Reuse

Borrowing it

Nothing to install: this file belongs to loopdive/js2. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/loopdive/js2/main/.claude/settings.json
Clone the repo
git clone --depth 1 https://github.com/loopdive/js2

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
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Your own site
<a href="https://agentmods.dev/hooks/loopdive/js2/pre-tool-use"><img src="https://agentmods.dev/badge/hooks/loopdive/js2/pre-tool-use/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for PreToolUse

Your own site · 80×15
<a href="https://agentmods.dev/hooks/loopdive/js2/pre-tool-use"><img src="https://agentmods.dev/badge/hooks/loopdive/js2/pre-tool-use.svg" alt="Reviewed on agentmods" width="80" 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. A grade says what 26 rules found in the file — not that it is safe.
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 1mo 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.

.claude/settings.json · 122 lines

How it starts

The opening of the file, as written. The whole thing — 122 lines — stays where its author put it; the contents beside it link to each section on GitHub.

{
  "PreToolUse": [
    {
      "matcher": "Bash",
      "if": "Bash(git checkout*)",
      "hooks": [
        {
          "type": "command",
          "command": "\"${CLAUDE_PROJECT_DIR:-/workspace}\"/.claude/hooks/check-cwd.sh",
          "timeout": 5
        }
      ]
    },
    {
      "matcher": "Bash",
      "if": "Bash(git add*)",
      "hooks": [
        {
          "type": "command",
          "command": "\"${CLAUDE_PROJECT_DIR:-/workspace}\"/.claude/hooks/pre-git-commit.sh",
          "timeout": 5
        }
      ]
    },
    {
      "matcher": "Bash",
      "if": "Bash(*--no-verify*)",
      "hooks": [
        {
          "type": "command",
          "command": "\"${CLAUDE_PROJECT_DIR:-/workspace}\"/.claude/hooks/block-no-verify.sh",
          "timeout": 5
        }
      ]
    },
    {
      "matcher": "Bash",
      "if": "Bash(git commit*)",
      "hooks": [
        {
          "type": "command",
          "command": "\"${CLAUDE_PROJECT_DIR:-/workspace}\"/.claude/hooks/pre-git-commit.sh",
          "timeout": 5
        }
      ]
    },
    {
      "matcher": "Bash",
      "if": "Bash(*git commit*)",
      "hooks": [
        {
          "type": "command",
          "command": "\"${CLAUDE_PROJECT_DIR:-/workspace}\"/.claude/hooks/check-commit-author.sh",
          "timeout": 5
        }
      ]
    },
    {
      "matcher": "Bash",
      "if": "Bash(git merge*)",
      "hooks": [
        {
          "type": "command",
          "command": "\"${CLAUDE_PROJECT_DIR:-/workspace}\"/.claude/hooks/pre-merge.sh",
          "timeout": 5
        }
      ]
    },
    {
      "matcher": "Bash",
      "if": "Bash(*worktree add*)",
      "hooks": [
        {
          "type": "command",
          "command": "\"${CLAUDE_PROJECT_DIR:-/workspace}\"/.claude/hooks/check-worktree-path.sh",
          "timeout": 5
        }
      ]
    },
    {
      "matcher": "Bash",
      "if": "Bash(*git push*)",
      "hooks": [
        {
          "type": "command",
          "command": "

Read the full file on GitHub · 122 lines

Same file

What else settings.json configures

This page is one entry in a file that holds 9. 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. 1mo ago Changed 8a4abb747a12
  2. 1mo ago Changed · +10 lines c57acbbe442c
  3. 2mo ago First seen · 112 lines scan A 979402dae50d

Subscribe to this mod's changes

PreToolUse is a hook published in the GitHub repository loopdive/js2 (67 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. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

Git and workflowSecurityTypeScriptaot-compilationcompilergarbage-collectionjavascriptwasm-gc
Related

PreToolUse compared with hooks from other repositories

PreToolUse next to 6 hooks from other repositories
ModTypeStarsLast pushLicenceScanTokensWorks with
PreToolUseloopdive/js2Hook67todayApache-2.0A—Claude Code
PostToolUsesupabase/supabaseHook115kyesterdayApache-2.0A—Claude Code
SessionStartsupabase/supabaseHook115kyesterdayApache-2.0A—Claude Code
SessionStartgoogle-gemini/gemini-cliHook109kyesterdayApache-2.0A—Claude Code
PreToolUseapache/supersetHook75ktodayApache-2.0A—Claude Code
PreToolUseanthropics/claude-cookbooksHook54k2d agoMITA—Claude Code
PostToolUseanthropics/claude-plugins-officialHook46kyesterdayApache-2.0A—Claude Code