agentmods.dev

PreToolUse

Hooks that run before the coding agent uses a tool, especially for task-related tool calls.

In plain words
What is it for?
Use them to run configured pre-tool or pre-task commands through shell scripts before the agent starts those actions.
Why use it?
They allow required checks or preparation commands to run before work begins, reducing the chance that tools operate without the expected setup.

Hook for Claude Code

1 yesterday A scan tokens not measured original MIT
View the source file sequant-io/sequant
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/sequant-io/sequant/pre-tool-use
Clone the repo
git clone --depth 1 https://github.com/sequant-io/sequant

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.

.claude/settings.json · 22 lines

What it actually says

{
  "PreToolUse": [
    {
      "matcher": "*",
      "hooks": [
        {
          "type": "command",
          "command": "\"$CLAUDE_PROJECT_DIR\"/.claude/hooks/pre-tool.sh"
        }
      ]
    },
    {
      "matcher": "Task",
      "hooks": [
        {
          "type": "command",
          "command": "entire hooks claude-code pre-task"
        }
      ]
    }
  ]
}
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 · 22 lines scan A 0cf96e89fb39

Subscribe to this mod's changes

PreToolUse is a hook published in the GitHub repository sequant-io/sequant (1 stars, last pushed yesterday), 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.

Code reviewGit and workflowPlanningagent-orchestratorai-coding-agentautonomous-agentclaude-codeclaude-code-plugin
Related

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SessionEnd

Runs when a session ends, executing node-hook-runner.sh via bash. From uditgoenka/autoresearch.

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PostToolUse

Runs after a tool call finishes for Edit and Write tool calls, running bun run lint. From gmickel/flow-next.

gmickel/flow-next · not measured

PreToolUse

Runs before the agent uses a tool for Bash tool calls, running bash. From fvadicamo/dev-agent-skills.

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SessionStart

Runs when a session starts, executing setup_env.sh via bash. From shepsci/kaggle-skill.

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