agentmods.dev

PostToolUse

A hook that runs a shell script after certain coding-agent actions finish, such as editing, writing, or using another agent. A hook is an automatic step attached to an event.

In plain words
What is it for?
Use it to capture records after task, agent, edit, write, multi-edit, or notebook-edit operations in the supported coding-agent environment.
Why use it?
It records evidence of completed tool actions without requiring a separate manual command. The supplied configuration calls a witness-record script after matching actions.

Hook

4 2d ago A scan tokens not measured original MIT
View the source file armanfatemi/nullius
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/armanfatemi/nullius/post-tool-use
Clone the repo
git clone --depth 1 https://github.com/armanfatemi/nullius
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

PostToolUse 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 2d 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.

plugin/hooks/hooks.json · 13 lines

What it actually says

{
  "PostToolUse": [
    {
      "matcher": "^(Task|Agent|Edit|Write|MultiEdit|NotebookEdit)$",
      "hooks": [
        {
          "type": "command",
          "command": "\"${CLAUDE_PLUGIN_ROOT}/hooks/witness-record.sh\""
        }
      ]
    }
  ]
}
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. 2d ago First seen · 13 lines scan A 616f615cd71d

Subscribe to this mod's changes

PostToolUse is a hook published in the GitHub repository armanfatemi/nullius (4 stars, last pushed 2d 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.

adrai-agentsciclaude-codecli
Related

Other hooks, from other repositories

SessionStart

Runs when a session starts on startup and resume, running bun run hook:session-start. From archgate/cli.

archgate/cli · not measured

WorktreeCreate

Runs when a git worktree is created, running bun run hook:worktree-create. From archgate/cli.

archgate/cli · not measured

PreToolUse

Runs before the agent uses a tool for Write, Edit and MultiEdit tool calls, running an inline shell check. From get-tmonier/argot.

get-tmonier/argot · not measured

SubagentStart

Runs when a subagent starts, executing run-hook.cmd. From rvdbreemen/adr-kit.

rvdbreemen/adr-kit · not measured

PostToolUse

Runs after a tool call finishes for Read, Write, Edit and AskUserQuestion tool calls, executing cli.mjs via node with --host and --model-provider (3 commands). From isaacriehm/cairn.

isaacriehm/cairn · not measured

UserPromptSubmit

Runs when you submit a prompt, before the agent sees it, executing cli.mjs via node with --host and --model-provider. From isaacriehm/cairn.

isaacriehm/cairn · not measured