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.
npx agentmods add hooks/romerma/mstack/subagent-stopgit clone --depth 1 https://github.com/romerma/mstackGrade 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 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.
What it actually says
{
"SubagentStop": [
{
"hooks": [
{
"type": "command",
"command": "${CLAUDE_PLUGIN_ROOT}/bin/mstack",
"args": [
"hook",
"subagent-stop"
],
"timeout": 10,
"description": "Confirm the subagent left its report on disk. A review subagent once went idle without writing one; the analysis lived only in its working context, which the parent never sees, so it would have vanished silently. A reply is not evidence, the file is."
}
]
}
]
}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.
- yesterday First seen · 18 lines scan A 430ead516d7e
SubagentStop is a hook published in the GitHub repository romerma/mstack (1 stars, last pushed 8d 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.
Other hooks, from other repositories
PostToolUse
Runs after a tool call finishes for Edit, Write, Edit and Write tool calls, executing auto-format-touched.sh and log-tdd-state-transition.sh (2 commands). From loiane/specs-driven-development-spring-angular.
UserPromptSubmit
Runs when you submit a prompt, before the agent sees it, executing route-natural-language-aliases.sh. From loiane/specs-driven-development-spring-angular.
SessionEnd
Runs when a session ends, executing yarbrain.py via python3. From yarlson/yarstack.
SessionEnd
Runs when a session ends, executing session-unlock.sh. From cowwoc/cat.
Stop
Runs when the agent finishes a response, executing stop-gate.sh via bash. From joanseg/specmanager.
SessionStart
Runs when a session starts, executing session-start.sh via bash. From codervisor/leanspec.