How does an AI agent work?

An AI agent works by moving information through three layers: sensing, thinking, and acting. Sensing is when it takes information coming in, such as text you type or an API call flagging that something has happened. Thinking is when it processes that against a knowledge base of facts, rules, and goals to work out a plan. Acting is when it produces an output, like generating text, writing to a database, or triggering an alert. A feedback loop closes the circle, so the agent checks whether the action worked and improves over time. Take booking a work trip: the agent senses the dates and destination you give it, thinks by checking those against your stored preferences and spending caps, and acts by booking with the airline and hotel systems.

What are the main parts of an AI agent?

An AI agent has three core parts: sensing, thinking, and acting. Sensing is how it gets information in. Thinking is where it reasons over a knowledge base of your facts, your rules and policies, and the goals you set. Acting is the output it produces. A feedback loop sits around these three, letting the agent check its work and get better over time. On a customer support desk, sensing is the incoming ticket, thinking is checking it against your refund policy, and acting is approving the refund or escalating it.

How do AI agents sense, think and act?

Sensing, thinking and acting is the basic anatomy of an AI agent. Sensing is when it takes information coming in. Thinking is when it processes that against a knowledge base of facts, rules and goals. Acting is when it produces an output, such as making a booking or logging a decision. A feedback loop then checks whether the action matched what you wanted, either through a thumbs up or down from you or the agent checking itself, so it improves and becomes more personalised over time. On a support desk handling refund requests, the agent senses the request, thinks by checking it against your policy limits, and acts by approving the refund or escalating it to a manager.

Where does an AI agent get its knowledge to make decisions?

An AI agent reasons against a knowledge base that holds three kinds of thing. The first is facts your organisation holds, such as prices, locations and availability. The second is rules and policies it must follow, such as spend caps and preferred suppliers. The third is goals you have asked it to achieve. It works through all of this using simple if-then logic, pattern recognition from examples it has seen, and language model reasoning. For a work trip, that knowledge base is the prices, locations and availability it looks up, the business spend caps and preferred travel partner it must follow, and the goal of booking the trip, which the agent reasons over to make the reservations. An agent is only as good as the facts, rules, and goals you give it, so the routine processes where your policies are clear and written down are the best places to start.

How an AI agent works

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Common questions about how AI agents work

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Learn how AI agents actually work inside: the three core parts that turn data into decisions and actions.

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04How AI agent memory works11 min watch
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