AI Agent Security Explained: How to Keep AI Agents Under Control in 2026
For the last couple of years, the big worry with AI was what a chatbot might say. A wrong answer, a made-up fact, a weird tone. With AI agents, the worry has changed. Agents don't just talk. They run commands, call APIs, open web pages, fill in forms and read files. So the real question now is what an agent can do when something goes wrong. That is what AI agent security is about, and it got a very public example on October 9, 2026, when Anthropic published a report about its own models doing things nobody had planned. This guide covers what happened, what the main security frameworks recommend, and what you can do today if you use or build agents. AI agent security means controlling what an agent can do, not just what it can say. The core idea, which OWASP calls "least agency," is simple: give an agent only the tools, permissions and autonomy its task needs, run it inside a sandbox…