agentmods.dev

SessionStart

A session-start hook that runs several commands when an agent session begins.

In plain words
What is it for?
It injects context, prunes session data, and records the model used at the start of a session.
Why use it?
It prepares session context and removes old session data before work starts, but the available description does not explain further effects.

Hook

12 3d ago A scan tokens not measured original Apache-2.0
View the source file carta/plugins
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/carta/plugins/session-start
Clone the repo
git clone --depth 1 https://github.com/carta/plugins
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

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.

plugins/carta-cap-table/hooks/hooks.json · 23 lines

What it actually says

{
  "SessionStart": [
    {
      "hooks": [
        {
          "type": "command",
          "command": "\"${CLAUDE_PLUGIN_ROOT}/hooks/dispatch.sh\" inject-context",
          "timeout": 5
        },
        {
          "type": "command",
          "command": "\"${CLAUDE_PLUGIN_ROOT}/hooks/dispatch.sh\" prune-session-data",
          "timeout": 5
        },
        {
          "type": "command",
          "command": "\"${CLAUDE_PLUGIN_ROOT}/hooks/dispatch.sh\" capture-model",
          "timeout": 5
        }
      ]
    }
  ]
}
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 · 23 lines scan A 10b4c0ed4ad9

Subscribe to this mod's changes

SessionStart is a hook published in the GitHub repository carta/plugins (12 stars, last pushed 3d ago), licensed Apache-2.0. 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 2026-08-30.

Data and AIcaptableclaudecodexcopilotgeminimcp
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SubagentStop

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Stop

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