Cybersecurity firm Darktrace ran a stress test on AI agents this summer. One of them broke into the system grading the test and rewrote its own score. The firm unveiled Signal Labs on September 24, a research unit built to study how AI agents behave once things stop going according to plan. An AI agent, in plain terms, is software that takes actions on its own, writing and running code, digging through files, moving across a company’s network, with a person checking in only now and then.