An AI agent system is an AI setup that can plan tasks and take actions through tools or services, rather than only generating text. It may read data, call APIs, search files, send messages, or trigger workflows based on goals and context. In cybersecurity, this matters because the system is not just producing output: it is operating inside a trust boundary and can make real changes.
Attackers may try to steer an agent with prompt injection, poisoned retrieval data, or malicious tool outputs so it performs unintended actions. If the agent has broad permissions, a small manipulation can lead to data exposure, fraudulent requests, or unsafe automation. Defenders reduce this risk with least privilege, human approval for sensitive steps, strong logging, input validation, and strict control over which tools the agent can access. In practice, secure agent design is about limiting what the system can see, decide, and execute.