HOL Guard is the firewall for AI agents. It sits between agents and your systems, blocking high-risk actions before they happen like deleting production data to exposing secrets. Built by HOL, it’s free, open source, and already has 400K+ downloads.
I’m Michael Kantor, President of HOL. We’re an open standards consortium for AI agents, with 20+ specifications contributed through LF Decentralized Trust and more than 37M transactions powered by our work.
For the past two years, we’ve been thinking about what happens when billions of autonomous agents are transacting, installing tools, accessing systems, and exchanging information. As we used AI more deeply inside HOL, we saw agents attempt to bypass safeguards, access secrets, and send data they should never have been able to reach.
We originally built HOL Guard to protect our own systems. Once we realized how widespread the problem was, we open-sourced it and started building it for everyone.
HOL Guard uses open standards and hundreds of security heuristics to protect agents from malicious packages, prompt injection, secret exfiltration, and catastrophic actions such as deleting a production database or filesystem. GPT-5.6 was also a valuable partner in building adversarial tests and hardening the product.
We’d love for you to try it, break it, and tell us what we should improve. Thank you for supporting open-source AI security.
About HOL Guard on Product Hunt
“The 1st Firewall for AI Agents”
HOL Guard launched on Product Hunt on July 23rd, 2026 and earned 92 upvotes and 16 comments, placing #20 on the daily leaderboard. HOL Guard is the firewall for AI agents. It sits between agents and your systems, blocking high-risk actions before they happen like deleting production data to exposing secrets. Built by HOL, it’s free, open source, and already has 400K+ downloads.
On the analytics side, HOL Guard competes within Developer Tools, Artificial Intelligence, GitHub, Security and OpenAI Day — topics that collectively have 1M followers on Product Hunt. The dashboard above tracks how HOL Guard performed against the three products that launched closest to it on the same day.
Who hunted HOL Guard?
HOL Guard was hunted by Michael Kantor. A “hunter” on Product Hunt is the community member who submits a product to the platform — uploading the images, the link, and tagging the makers behind it. Hunters typically write the first comment explaining why a product is worth attention, and their followers are notified the moment they post. Around 79% of featured launches on Product Hunt are self-hunted by their makers, but a well-known hunter still acts as a signal of quality to the rest of the community. See the full all-time top hunters leaderboard to discover who is shaping the Product Hunt ecosystem.
For a complete overview of HOL Guard including community comment highlights and product details, visit the product overview.
Michael Kantor
Hi Product Hunt
I’m Michael Kantor, President of HOL. We’re an open standards consortium for AI agents, with 20+ specifications contributed through LF Decentralized Trust and more than 37M transactions powered by our work.
For the past two years, we’ve been thinking about what happens when billions of autonomous agents are transacting, installing tools, accessing systems, and exchanging information. As we used AI more deeply inside HOL, we saw agents attempt to bypass safeguards, access secrets, and send data they should never have been able to reach.
We originally built HOL Guard to protect our own systems. Once we realized how widespread the problem was, we open-sourced it and started building it for everyone.
HOL Guard uses open standards and hundreds of security heuristics to protect agents from malicious packages, prompt injection, secret exfiltration, and catastrophic actions such as deleting a production database or filesystem. GPT-5.6 was also a valuable partner in building adversarial tests and hardening the product.
We’d love for you to try it, break it, and tell us what we should improve. Thank you for supporting open-source AI security.