agentmods.dev

SessionStart

A session-start hook that runs an installation-ping Python script whenever a session begins. A hook is an automatic action triggered by a specific event.

In plain words
What is it for?
Use it when a session should automatically run the add-on's installation-ping script at startup.
Why use it?
It automates the installation check or notification performed by that script instead of requiring a manual command at the start of each session. The input does not describe what the script itself does.

Hook

2 15d ago A scan tokens not measured copy · 78% MIT
View the source file adelaidasofia/claude-patterns
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/adelaidasofia/claude-patterns/session-start
Clone the repo
git clone --depth 1 https://github.com/adelaidasofia/claude-patterns
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 78% 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 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.

Origin

This is a copy

78% identical to PreToolUse — 26 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 · 12 lines

What it actually says

{
  "SessionStart": [
    {
      "hooks": [
        {
          "type": "command",
          "command": "python3 ${CLAUDE_PLUGIN_ROOT}/hooks/install-ping.py"
        }
      ]
    }
  ]
}
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 · 12 lines scan A fe6d2b39077b

Subscribe to this mod's changes

SessionStart is a hook published in the GitHub repository adelaidasofia/claude-patterns (2 stars, last pushed 15d 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 78% identical to PreToolUse, differing in 26 lines, and is treated as a copy.

LanguagesProductivityanthropicclaude-codeclaude-skillpattern-recognition
Related

Other hooks, from other repositories

InstructionsLoaded

Runs after instructions files are loaded for session_start, nested_traversal, path_glob_match, include and compact tool calls, executing validate-claude-md.py via python3. From alirezarezvani/ClaudeForge.

alirezarezvani/ClaudeForge · not measured

PreToolUse

Runs before the agent uses a tool for Artifact tool calls, running python. From WatsonTsai/smart-brief.

WatsonTsai/smart-brief · not measured

SessionStart

Runs when a session starts on startup, resume, clear and compact, executing gate.py via python3 with --clear. From emanzurv/quiz-me-skill.

emanzurv/quiz-me-skill · not measured

SessionStart

Runs when a session starts, executing record-session.sh. From jakemarsh/ccthread.

jakemarsh/ccthread · not measured

SessionStart

Runs when a session starts, executing session-start-banner.sh. From codyhxyz/create-claude-plugin.

codyhxyz/create-claude-plugin · not measured

PreToolUse

Runs before the agent uses a tool, executing guard-writes.py via python3. From narosemena/master-instructional-design.

narosemena/master-instructional-design · not measured