Parry

Parry-guard

[](https://github.com/vaporif/parry/actions/workflows/check.yml) [](https://github.com/hesreallyhim/awesome-claude-code)

Prompt injection scanner for Claude Code hooks. Scans tool inputs and outputs for injection attacks, secrets, and data exfiltration attempts.

**Early development** — this tool is under active development and may have bugs or false positives. Tested on linux/macOS.

Prerequisites

The ML models are gated on HuggingFace. Before installing:

1. Create an account at huggingface.co
2. Accept the DeBERTa v3 license (required for all modes)
3. For full mode: also accept the Llama Prompt Guard 2 license (Meta approval required)
4. Create an access token at huggingface.co/settings/tokens

Usage

Add to `~/.claude/settings.json`:

**With [uvx](https://docs.astral.sh/uv/):**

{
  "hooks": {
    "PreToolUse": [{ "command": "uvx parry-guard hook", "timeout": 1000 }],
    "PostToolUse": [{ "command": "uvx parry-guard hook", "timeout": 5000 }],
    "UserPromptSubmit": [{ "command": "uvx parry-guard hook", "timeout": 2000 }]
  }
}

**With [rvx](https://github.com/vaporif/rvx):**

{
  "hooks": {
    "PreToolUse": [{ "command": "rvx parry-guard hook", "timeout": 1000 }],
    "PostToolUse": [{ "command": "rvx parry-guard hook", "timeout": 5000 }],
    "UserPromptSubmit": [{ "command": "rvx parry-guard hook", "timeout": 2000 }]
  }
}

**With parry-guard on PATH** (via [Nix](#nix-home-manager), cargo install, or [release binary](https://github.com/vaporif/parry/releases)):

{
  "hooks": {
    "PreToolUse": [{ "command": "parry-guard hook", "timeout": 1000 }],
    "PostToolUse": [{ "command": "parry-guard hook", "timeout": 5000 }],
    "UserPromptSubmit": [{ "command": "parry-guard hook", "timeout": 2000 }]
  }

...