---
title: README
emoji: 🛡️
colorFrom: indigo
colorTo: gray
sdk: static
pinned: false
---

# 🛡️ Patronus Protect

**An on-device AI firewall.** It watches the AI traffic going in and out of your apps —
browsers, IDEs, native apps, MCP servers — and blocks what shouldn't get through: prompt
injections, leaked secrets, shadow AI. Everything runs locally, nothing is sent to a cloud,
and it works with any provider (Claude, OpenAI, Gemini, Copilot, Ollama, …).

## Patronus Ark

**Patronus Ark** is the scanning engine underneath the app: a Rust core with Python
bindings that scans in three escalating layers, so most traffic is resolved before a
transformer ever runs.

| Layer | What runs | Cost |
| --- | --- | --- |
| **L1** | Native rule-based detectors | microseconds |
| **L2** | Small classifiers sharing one encoder | milliseconds |
| **L3** | Full quantized transformers, lazily loaded | only for the uncertain rest |

Across those layers it catches prompt injection and jailbreaks, PII, secrets and DLP leaks,
sensitive documents, risky agentic tool use and MCP policy violations, plus routing and
threat classification — all on the endpoint.

Ark will be open source (dual license available). It is **not public yet**
— the repository link will appear here at launch.

## The models 🤗

Our detectors, trained for the firewall and shared openly — use them, fine-tune them,
benchmark against them, and tell us where they fall short:

- 🐺 **Wolf Defender** — prompt-injection detection and threat classification (EN/DE)
- 🫍 **Orca Sonar** — document classification for DLP and sensitive-document routing
- 🦁 **Lion Warden** — one unified seven-head AI-security model
- 🐕 **Husky** (Sight / Paw / Nose) — agentic tool use: tool type, operation, data-flow risk
- 🐆 **Panther Read** — user-intent and request routing
- 🦈 **Shark Scent** — PII detection
- **GLiNER Edge** — quantized zero-shot entity extraction (upstream GLiNER, Apache-2.0)

Deliberately small: ModernBERT under the hood, ONNX-quantized (INT8/INT4), a few hundred
MB of RAM — they run happily on a laptop instead of a GPU rack.

The app, with downloads for macOS and Windows, lives at
[patronus.studio](https://patronus.studio). Come say hi.