Doesn't help the conversation that some LLM chat systems call minor customization of the prompt making an agent.

Under duress I use CoPilot Chat at work. No, the basic sad customization I did along the lines of "don't be sycophantic, always cite sources, use these specific official documentation sites as sources before searching outside of them and clearly call out when you search outside them" that customization isn't making a damn agent, it's adjusting the prompt and saving those changes you disingenuous marketing fucks!