What's the heart of an AI agent?

At its most fundamental form, an AI agent consists of a model, tools, and instructions^[1]. The language model powers the agent's reasoning and decision-making^[1][2]. Tools are external functions or APIs that the agent utilizes to take action^[1][2]. Instructions are explicit guidelines and guardrails defining how the agent behaves^[1].

The architecture of an AI agent also includes an orchestration layer, which is a cyclical process for assimilating information, reasoning, and using that reasoning to decide on the next action^[2]. It maintains memory, state, reasoning, and planning^[2].