What does it mean to you?
1. Have a goal (hard-coded, taken as input, etc)
2. Create a plan (of steps or tasks) to achieve the goal
3. Execute (the steps or tasks in) the plan to achieve the goal (often including tool use)
4. Sometimes they check for success against the goal and/or re-plan based on current status
Love your blog BTW
For another definition that incorporates these elements (explicitly or implicitly), see Llamaindex's high level concepts page [1]:
"Agents: An agent is an automated decision maker powered by an LLM that interacts with the world via a set of tools. Agents can take an arbitrary number of steps to complete a given task, dynamically deciding on the best course of action rather than following pre-determined steps. This gives it additional flexibility to tackle more complex tasks."
[1] https://docs.llamaindex.ai/en/stable/getting_started/concept...