According to Daniel Dennett, agents are things in the world that benefit from a rational system—that is, their actions have rationale—without necessarily understanding the system. For example, a thermostat adjusts activity and exploits information in the environment for a reason: to regulate temperature.
Unlike non-human agents such as animals and AlphaGo, humans evolved to comprehend a space of reasons and are uniquely “obliged to articulate our reasons.” However, in general, the rationale behind our actions is subconscious. As another example, @1975griceLogic’s maxims of conversation explicitly state the “free-floating rationales of human communication”—the reasons that communication works the way it does—but no one actually references these when having a conversation.