What an Agent Actually Is

1. The Defining Property: Who Chooses the Next Step

Strip the hype away and there is one test that matters. In a workflow, the engineer decided the steps ahead of time, at design time. The model just fills in the slots along a fixed path: transcribe, then summarize, then extract action items. That is three LLM calls and zero decisions about what happens next. In an agent, the model itself chooses the next step, at runtime, based on what it has seen so far.