Agents are LLM responses that are feed with tools, like calculate(expression). When it encounters a thing it needs to do to meet desired output, it will run the tool. That is defining a simple agentic workflow.

A complicated workflow may involve other tools. For example, the input to the LLM may produce something that tells it to set the user-agent to such and such as string:

  set_user_agent("Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36");