What is an AI agent? Explained with an assistant you send on errands
An AI agent takes a goal, plans the steps and carries them out with software tools, checking each result as it goes. Explained with an assistant you send on errands.
- Author
Umair Mateen- Published
- Reading time
- 5 min
- Category
- AI
In one sentence: an AI agent is an AI system that takes a goal from you, plans the steps, and carries them out on its own by using software tools, checking each result and deciding what to do next until the job is done or it needs you.
The everyday picture
Think of an assistant you can send on errands. You do not hand them a list of every step. You give them a goal: "Get everything we need for Friday's team lunch."
The assistant works out the plan. They visit the shops, check what is in stock, and read each receipt. If the bakery is sold out, they go to the next one. Before spending a lot of money, they call you to check.
A plain AI chatbot is more like someone who answers questions at a desk. An agent leaves the desk and gets things done.
You give the agent a goal. It uses a tool, reads what comes back and picks its next step, looping until the job is done. Before a risky step, it checks with you.
How it works, step by step
- You set the goal (you send the assistant out). You describe the task in plain words, along with any rules, such as a budget or what it must not touch.
- The AI model plans (the assistant thinks it through). A large language model, the "brain" of the agent, decides the first step. The company or developer setting it up gives it instructions, like a written job description.
- It uses a tool (the assistant visits a shop counter). Tools are pieces of software the agent is allowed to use: search the web, read a calendar, look up an order, send an email.
- It reads the result and decides again (the assistant reads the receipt). Each tool sends back a result. The agent checks it and picks the next step. This repeats in a loop until the goal is met or a set limit is reached.
- It checks in with you (the phone call before a big purchase). A well-built agent stops and asks a person before risky steps, such as making a payment or sending a refund.
Where the picture stops
- It is not a person with common sense. The agent is an AI model making predictions. It can misread a result, and on a long errand one small mistake can lead to the next. Anthropic warns that errors can build up over many steps.
- It can only visit the shops you open to it. A human assistant can wander anywhere. An agent can only use the tools it has been given, which is also how you keep it safe.
- It does not always call you on its own. The check-in has to be built in by whoever sets up the agent. It is a rule in the software, not good manners.
Why it matters for your business
- Speed on messy tasks. Agents suit work that needs judgement and many steps, and that is hard to write down as fixed rules. OpenAI's guide points to tasks with complex decisions, rules that are hard to maintain, or lots of emails and documents.
- Cost to watch. Every step of the loop uses the AI model again, so agents usually cost more and take longer than a single answer. Anthropic advises starting with the simplest solution and adding an agent only when it clearly helps.
- Risk to manage. An agent that can act can also act wrongly. Give it only the tools it needs, test it safely first, and keep a person approving actions that move money or customer data.
- Standards are forming. In February 2026, the US standards body NIST launched an initiative on agent security and on how agents prove who they act for. Expect more guidance on safe use.
An example
Imagine a 12-person interior design studio that spends hours each week chasing supplier quotes.
They set up an AI agent with three tools: read the shared inbox, look up the studio's price list, and draft replies. When a client asks for a sofa in a new fabric, the agent finds the supplier email, checks the price list, notices the fabric is missing, and asks the supplier for a quote. When the quote arrives, it drafts the order. It then waits for a designer to approve before anything is sent.
Frequently asked questions
What is the difference between an AI agent and a chatbot?
A chatbot answers you in a conversation. An AI agent works towards a goal by taking actions with tools, such as looking things up or updating a system, and decides its own next steps.
What is the difference between an AI agent and an automated workflow?
A workflow follows a fixed path that someone designed in advance. An agent chooses its own path as it goes, which makes it more flexible but less predictable.
Can AI agents make mistakes?
Yes. They can misunderstand a goal or a result, and mistakes can grow over many steps. That is why good agents have limits, testing and a person approving risky actions.
Do I need to code to use an AI agent?
Not always. Many AI apps now include agent features you can use by typing a request. Connecting an agent safely to your own business systems usually needs technical setup.
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