Everything you have built so far is reactive.
User sends a message. System processes it. System sends a response. Done.
An agent is different. An agent receives a goal, not a message. It decides what steps to take to achieve that goal. It uses tools. It observes the results. It adjusts its plan. It continues until the goal is achieved or it determines the goal cannot be achieved.
"Summarize this document" is a task. One call. One response.
"Research recent papers on transformer efficiency, write a comparison table, and save it as a CSV" is a goal. An agent needs to search the web multiple times, decide which papers are relevant, extract data from multiple sources, format it consistently, handle failures, and write to disk. Five to twenty tool calls. Dynamic decisions at each step.
