Typically, the term "agents" implies some autonomous collaboration. In an agent workflow, the flow itself is non-deterministic. One agent can work with another agent and keep cycling between themselves until an output is resolved that meets some criteria. An agent itself is also typically evaluating the terminal condition for the workflow.
It's also used to mean "characters interacting with each other" and sort of message passing between them. Not sure but I get the sense thats what the author is using it as
Some "agents" like the minecraft bot Voyager(https://github.com/MineDojo/Voyager) have a control loop, they are given a high level task and then they use LLM to decide what actions to take, then evaluate the result and iterate. In some LLM frameworks, a chain/pipeline just uses LLM to process input data(classification, named entitiy extraction, summary, etc).
