# Gate.cat: Stopping AI Agents from Running rm -rf

> Source: <https://promptcube3.com/en/threads/2489/>
> Published: 2026-07-23 19:02:11+00:00

# Gate.cat: Stopping AI Agents from Running rm -rf

*after*the command finishes. Gate.cat actually intercepts the execution before the shell even sees the command.

The core logic here is fail-closed: if the tool can't parse the command, it blocks it. Crucially, there is no LLM call in the veto path. This means a clever prompt injection can't "convince" the gate to let a dangerous command through because the gate isn't listening to the model; it's analyzing the string and path.

## Deployment Options

Depending on your AI workflow, there are three ways to plug this in:

1. ** Claude Code hook**: This is the most secure method since enforcement happens in the harness. Run

`pip install gate.cat`

and update your `.claude/settings.json`

by adding `gatecat-hook`

to the matcher for `Bash|Write|Edit`

.2.

**Gated shell**: Works for any CLI agent that honors the

`$SHELL`

variable (like aider or Codex) via `gatecat-shell`

.3.

**Local proxy**: For those using Ollama, vLLM, or OpenRouter, you can just swap the

`base_url`

to route through the proxy.## Performance Data

The project includes a `FACTS.md`

file with reproducible artifacts. According to their data:

**Command Testing:** 1,085,159 unique agent commands from public datasets were replayed; zero misses after adjudication.**Bypass Suite:** 178/178 dangerous shapes were successfully caught.**Intervention Rate:** Only ~0.6% of real-world commands are actually blocked, meaning it doesn't get in the way of actual work too often.**Policy Walls:** Comes with 71 default policy walls.

## The Reality Check

This isn't a magical "safety proof." It's a wall against known-dangerous patterns. If a command doesn't match a danger shape, it goes through. It should be used as a layer of defense *alongside* a sandbox, not as a replacement for one.

It's Apache-2.0 and has a zero-dependency core.

```
pip install gate.cat
```

Specific project details:

```
https://github.com/BGMLAI/gate.cat
```

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