PreToolUse

Commands that run before the agent uses Bash, Read, or Grep tools. They take repository snapshots, check documentation, guard Git operations, validate pull-request text, and run local commit and lint checks.

In plain words
What is it for?
Use them to enforce project-specific checks around shell commands, file reads, searches, commits, pull requests, and staged files.
Why use it?
They catch unsafe repository actions and common quality problems before the agent's tool use proceeds.

Hook for Claude Code

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/optave/ops-codegraph-tool/pre-tool-use
Clone the repo
git clone --depth 1 https://github.com/optave/ops-codegraph-tool

Made for: Claude Code.

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 yesterday.

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

Copies of this mod

1 near-identical copy found in the catalogue:

.claude/settings.json · 64 lines

How it starts

The opening of the file, as written. The whole thing — 64 lines — stays where its author put it; the contents beside it link to each section on GitHub.

{
  "PreToolUse": [
    {
      "matcher": "Bash",
      "hooks": [
        {
          "type": "command",
          "command": "p=\"${CLAUDE_PROJECT_DIR}\"; [ -d \"$p/.claude/hooks\" ] || p=\"$(git rev-parse --show-toplevel 2>/dev/null)\"; [ -d \"$p/.claude/hooks\" ] || exit 0; bash \"$p/.claude/hooks/snapshot-pre-bash.sh\"",
          "timeout": 5
        },
        {
          "type": "command",
          "command": "p=\"${CLAUDE_PROJECT_DIR}\"; [ -d \"$p/.claude/hooks\" ] || p=\"$(git rev-parse --show-toplevel 2>/dev/null)\"; [ -d \"$p/.claude/hooks\" ] || exit 0; bash \"$p/.claude/hooks/check-readme.sh\"",
          "timeout": 10
        },
        {
          "type": "command",
          "command": "p=\"${CLAUDE_PROJECT_DIR}\"; [ -d \"$p/.claude/hooks\" ] || p=\"$(git rev-parse --show-toplevel 2>/dev/null)\"; [ -d \"$p/.claude/hooks\" ] || exit 0; bash \"$p/.claude/hooks/guard-git.sh\"",
          "timeout": 10
        },
        {
          "type": "command",
          "command": "p=\"${CLAUDE_PROJECT_DIR}\"; [ -d \"$p/.claude/hooks\" ] || p=\"$(git rev-parse --show-toplevel 2>/dev/null)\"; [ -d \"$p/.claude/hooks\" ] || exit 0; bash \"$p/.claude/hooks/guard-pr-body.sh\"",
          "timeout": 10
        },
        {
          "type": "command",
          "command": "p=\"${CLAUDE_PROJECT_DIR}\"; [ -d \"$p/.claude/hooks\" ] || p=\"$(git rev-parse --show-toplevel 2>/dev/null)\"; [ -d \"$p/.claude/hooks\" ] || exit 0; bash \"$p/.claude/hooks/commitlint-local.sh\"",
          "timeout": 10
        },
        {
          "type": "command",
          "command": "p=\"${CLAUDE_PROJECT_DIR}\"; [ -d \"$p/.claude/hooks\" ] || p=\"$(git rev-parse --show-toplevel 2>/dev/null)\"; [ -d \"$p/.claude/hooks\" ] || exit 0; bash \"$p/.claude/hooks/pre-commit.sh\"",
          "timeout": 60
        },
        {
          "type": "command",
          "command": "p=\"${CLAUDE_PROJECT_DIR}\"; [ -d \"$p/.claude/hooks\" ] || p=\"$(git rev-parse --show-toplevel 2>/dev/null)\"; [ -d \"$p

Read the full file on GitHub · 64 lines

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. yesterday First seen · 64 lines scan A c055b118165a

Subscribe to this mod's changes

PreToolUse is a hook published in the GitHub repository optave/ops-codegraph-tool (92 stars, last pushed 3d ago), 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.