The best non technical explanation you can give is "An AI agent is an LLM that can take actions".

While an agent doesn't necessarily have to be powered by an LLM, most modern AI agents are.

You pointing at a human brain does not change that an AI agent is not intelligent and cannot think, we are still talking about probability built on statistics with extra steps.

I am not trying to be dishonest, we should stop making analogies between AI and actual thinking, because they are two entire different concepts.

Who developed these technologies used the words "thinking" and "reasoning", this does not mean they are actually thinking and reasoning. Somewhere you still have a processor calculating, with no empathy.

So, again: stop humanizing AI. This sentence shouldn't make you angry.