SubagentStop

SubagentStop is a hook for coding agents from GaZmagik/claude-memory-plugin. Its token cost is not measured, scanned A, original, MIT.

A hook that runs when a subagent finishes and starts a script to extract its agent ID. A subagent is a secondary agent working on part of a larger task.

In plain words
What is it for?
Automatically recording subagent IDs after subagents stop, using a Bun script.
Why use it?
It preserves the identifier needed to refer to a completed subagent or continue work associated with it.

Hook

Part of the claude-memory-plugin plugin — 1 skill, 5 commands, 2 agents, 7 hooks shipped together

One of 7 entries in hooks.json — they are configured in one file and arrive together.

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/gazmagik/claude-memory-plugin/subagent-stop
Clone the repo
git clone --depth 1 https://github.com/GaZmagik/claude-memory-plugin

Or install claude-memory-plugin, the plugin that ships this one along with the rest of its 1 skill, 5 commands, 2 agents, 7 hooks.

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 SubagentStop

README.md
[![agentmods](https://agentmods.dev/badge/hooks/gazmagik/claude-memory-plugin/subagent-stop.svg)](https://agentmods.dev/hooks/gazmagik/claude-memory-plugin/subagent-stop)
Your own site
<a href="https://agentmods.dev/hooks/gazmagik/claude-memory-plugin/subagent-stop"><img src="https://agentmods.dev/badge/hooks/gazmagik/claude-memory-plugin/subagent-stop.svg" alt="Measured on agentmods" 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. Scan, not verified.
Origin original No closer match found in the catalogue.
Security

Grade A, and why

SubagentStop 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 · 13 lines

What it actually says

{
  "SubagentStop": [
    {
      "hooks": [
        {
          "type": "command",
          "command": "bun ${CLAUDE_PLUGIN_ROOT}/hooks/subagent-stop/extract-agent-id.ts",
          "timeout": 5
        }
      ]
    }
  ]
}
Same file

What else hooks.json configures

This page is one entry in a file that holds 7. 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 · 13 lines scan A a33c939cbd22

Subscribe to this mod's changes

SubagentStop is a hook published in the GitHub repository GaZmagik/claude-memory-plugin (6 stars, last pushed 5mo 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.