agentmods.dev

SessionStart

A startup hook that runs a session-start script when a Claude Code session starts, resumes, is cleared, or is compacted.

In plain words
What is it for?
It is for running session initialization during startup, resume, clear, and context-compaction events.
Why use it?
It lets the Patrol plugin perform its session setup automatically at those lifecycle points.

Hook

3 5mo ago A scan tokens not measured copy · 81% MIT
View the source file cukas/patrol
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/cukas/patrol/session-start
Clone the repo
git clone --depth 1 https://github.com/cukas/patrol
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 81% copy Near-identical to another mod in the catalogue.
Security

Grade A, and why

SessionStart 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

This is a copy

81% identical to SessionStart — 4 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

hooks/hooks.json · 15 lines

What it actually says

{
  "SessionStart": [
    {
      "matcher": "startup|resume|clear|compact",
      "hooks": [
        {
          "type": "command",
          "command": "${CLAUDE_PLUGIN_ROOT}/hooks/session-start.sh",
          "timeout": 10,
          "async": false
        }
      ]
    }
  ]
}
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 · 15 lines scan A 3e18b4106aa6

Subscribe to this mod's changes

SessionStart is a hook published in the GitHub repository cukas/patrol (3 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. It is 81% identical to SessionStart, differing in 4 lines, and is treated as a copy.

Code reviewDebuggingclaude-codeclaude-code-pluginclaude-code-pluginscode-qualitydebuggdeveloper-tools
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SessionStart

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SessionStart

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