Intentionality implies self-awareness and drive
Human actions are driven by needs to achieve physical homeostasis, to repeat a past behavior that resulted in dopamine reward or other physical drive (Antonio Damasio). Over time, self-awareness has evolved that enables the mind to consider oneself as an agent, project outcomes of actions and intentionally select optimal ones. Neither all mental states nor mother nature are necessarily intentional, but a mental state, mother nature or robot might have intention.