ThumbGate — PreToolUse Agent Firewall for Gemini CLI

io.github.igorganapolsky/thumbgate

Sub-ms PreToolUse firewall, feedback memory, and single-use permits for AI coding agents.

client:Gemini CLI transport:stdio runtime:npm

Install ThumbGate — PreToolUse Agent Firewall in Gemini CLI

~/.gemini/settings.json · windows: %USERPROFILE%\.gemini\settings.json

{
  "mcpServers": {
    "thumbgate": {
      "command": "npx",
      "args": [
        "-y",
        "thumbgate"
      ]
    }
  }
}

Gemini expands $VAR and ${VAR} inside env values, so a secret can live in your shell rather than this file. Gemini CLI docs