What is SessionStart?

A session-start hook that runs five setup and maintenance commands when a coding-agent session begins, including loading context and merging settings.

Repairing hooks, preserving the Kitty terminal environment, loading context, refreshing cached information and combining system and user settings.

It prepares the session automatically and keeps context, settings and cached information up to date.

SessionStart — Hook by danielmiessler

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/danielmiessler/lifeos/session-start

Clone the repo

git clone --depth 1 https://github.com/danielmiessler/LifeOS

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 B 1 finding. Scan, not verified.

Origin original No closer match found in the catalogue.

Security

Grade B, and why

SessionStart scanned grade B with 1 finding 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.

Reads agent configuration directoriesmediumAgent snooping

.claude/, .codex/, .gemini/ hold keys, settings and other credentials a mod has no legitimate need for.

"command": "bun $HOME/.claude/LIFEOS/TOOLS/SettingsBackport.ts; bun $HOME/.claude/LIFEOS/TOOLS/MergeSettings.ts --system $HOME/.claude/settings.system.json --user $HOME/.claude/LIFEOS/USER/CONFIG/settings.user.json --out

LifeOS/install/hooks/hooks.json · 33 lines

What it actually says

{
  "SessionStart": [
    {
      "hooks": [
        {
          "type": "command",
          "command": "bun $HOME/.claude/hooks/HookHealer.hook.ts",
          "timeout": 10
        },
        {
          "type": "command",
          "command": "$HOME/.claude/hooks/KittyEnvPersist.hook.ts"
        },
        {
          "type": "command",
          "command": "$HOME/.claude/hooks/LoadContext.hook.ts"
        },
        {
          "type": "command",
          "command": "bun $HOME/.claude/LIFEOS/TOOLS/FreshnessCache.ts --quiet",
          "timeout": 5,
          "async": true
        },
        {
          "type": "command",
          "command": "bun $HOME/.claude/LIFEOS/TOOLS/SettingsBackport.ts; bun $HOME/.claude/LIFEOS/TOOLS/MergeSettings.ts --system $HOME/.claude/settings.system.json --user $HOME/.claude/LIFEOS/USER/CONFIG/settings.user.json --output $HOME/.claude/settings.json",
          "timeout": 15,
          "async": true
        }
      ]
    }
  ]
}

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.

yesterday First seen · 33 lines scan B 714051ef5046

Subscribe to this mod's changes

SessionStart is a hook published in the GitHub repository danielmiessler/LifeOS (18,798 stars, last pushed 17d ago), licensed MIT. Its token cost is not measured: a hook is shell that never enters the context. A static security scan graded it B with 1 finding (reads agent configuration directories). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

Productivity ai ai-harness augmentation humans intent-engineering

SessionStart

Getting it into your agent

Grade B, and why

Reads agent configuration directoriesmediumAgent snooping

What it actually says

What this file has done since we first saw it

Other hooks, from other repositories

PreCompact

SessionStart

PreToolUse

PostToolUse

UserPromptSubmit

Stop