Imagination. When the AI is capable not just of describing something but of extrapolating the rest of its existence in order to complete a task. For instance, any puppy understands the basics of information flow. A dog can lie. A dog can be fed by owner A and then tell owner B that A forget. The puppy can imagine the mental states of both owners, extrapolate that they have not coordinated the meal delivery today, identify that information gap, then leverage that understanding into getting two meals instead of one. That's the level of complexity I expect before an AI can be said to be aware of its environment.