Gemini CLI

A Gemini CLI BeforeTool hook sends each shell command to dagsec before it runs. Install commands are checked; everything else is allowed and nothing is stored.

Setup

1. Create an API key.
2. Add this to ~/.gemini/settings.json (merge it into existing settings), replacing YOUR_DAGSEC_API_KEY:

{
  "hooks": {
    "BeforeTool": [
      {
        "matcher": "run_shell_command",
        "hooks": [
          {
            "name": "dagsec",
            "type": "command",
            "command": "curl -s -m 15 -H \"Authorization: Bearer YOUR_DAGSEC_API_KEY\" -H \"Content-Type: application/json\" --data-binary @- https://app.dagsec.net/api/hooks/gemini",
            "timeout": 20000
          }
        ]
      }
    ]
  }
}

On Windows, write curl.exe instead of curl. The Integrations page in the dashboard shows this ready to copy.

What it does

Result	Gemini CLI
Not an install, or nothing risky	The command runs
Risky, block mode	The command is denied and the reason is shown to you and the agent
Risky, warn mode	The finding is shown and the command runs, because Gemini CLI can't ask

Warn mode: add ?mode=warn to the URL or send X-Dagsec-Mode: warn. The recognized commands and rules are the same as for Cursor.

Failure behaviour

If dagsec can't be reached or the key is wrong, the command runs.