HOL Guard: Open-Source Antivirus for AI Agents

	Stop risky AI actions before they compromise your machine. HOL Guard is a local-first security layer for AI agents, tools, plugins, skills, MCP servers, and package installs.Install HOL GuardRead the documentationPyPI Package (hol-guard)Report an Issue

HOL Guard reviews agent actions before they run: shell commands, file access, package installs, and MCP tool calls. It detects secret exposure, destructive operations, prompt injection, and supply-chain risks, then allows, blocks, or requests approval according to your policy.

Run it locally without an account. Use the CLI and local dashboard to manage protection, resolve approvals, and inspect decision history. Optional Guard Cloud adds shared history, team policy, and fleet management.

Get started · Supported agents · Plugin scanner · Documentation · Contribute an extension · Development

Install HOL Guard

Requires Python 3.10 or newer and pipx.

pipx install hol-guard
hol-guard init

The first-run wizard discovers supported agents and walks you through protection setup. It asks before each setup change, including opening the dashboard, installing agent integrations, and connecting optional cloud services.

Check your installation:

hol-guard --version
hol-guard status

To update an existing installation:

hol-guard update

For manual setup, see the installation guide. Annotated release notes with upgrade context live at hol.org/guard/releases; raw releases and prereleases are on the GitHub releases page.

What HOL Guard Protects

Surface	Protection
Shell commands and file access	Reviews destructive operations, sensitive file access, credential exposure, and suspicious outbound commands.
Package installs	Evaluates supported package-manager operations against supply-chain intelligence before installation.
Plugins, skills, and agent configuration	Inventories local artifacts and reviews new or changed tools before launch.
MCP servers and tools	Inspects server configuration and reviews tool calls through supported hooks and managed proxies.
Prompts and tool results	Screens supported events for prompt injection and sensitive content.
Approvals and evidence	Routes decisions to native prompts or the approval center, and records local receipts for review.

Guard connects through native agent hooks, managed MCP proxies, and launch integrations. Coverage depends on the events each agent exposes; the support matrix documents enforcement, approval delivery, and failure behavior per integration.

Supported AI Agents