What is AI agent security
AI agent security is the practice of monitoring and controlling what an autonomous AI agent actually does, its tool calls, its network connections, and its data access, as it runs. It is distinct from model safety (training and alignment) and from prompt guardrails (screening the text going in and out). Agent security is about the actions.
Why agents need their own security layer
An AI agent is given tools and goals and then decides, on its own, what to do. That autonomy is the value and the risk. The same agent that books travel can be steered, by a prompt injection or a compromised tool, into reading secrets or exfiltrating data, often using only actions it was technically allowed to take. Three properties make this hard:
- Allowed is not safe. An action can be permitted by policy and still be malicious in context. Allowlists and content filters pass it.
- The narration can lie. What the agent reports it did is generated text. It can be wrong or deliberately misleading.
- Behavior drifts. An agent that has acted one way for months can suddenly do something it has never done. Static rules miss the new pattern.
What a behavioral approach looks like
Kaizen treats agent security as a behavioral problem:
- Learn the baseline. For each agent, learn the tools, destinations, and patterns it normally uses.
- Judge the action, not the narration. Evaluate what the agent actually did against its baseline and what you declared, with a deterministic check and a selective reasoning check. See how Kaizen decides.
- Observe as deeply as you need. From a cooperative SDK hook up to a ground-truth egress collector, the deeper you attach, the less an agent can do that you cannot see. See observation depth.
- Decide in your tenant. The strongest mode, the Kaizen Sandbox, makes the whole decision in your own environment and sends out only the verdict.
How it compares to adjacent tools
- Sandboxes contain an agent and block unknown hosts; they cannot tell you the agent exfiltrated to an allowed host. See Kaizen and your sandbox.
- Prompt guardrails screen content; Kaizen judges behavior. See Kaizen and prompt guardrails.