L026 · Under the hood · 2 min · Interactive
AI agents: AI that takes action
An agent is AI that does not just answer but takes steps: it plans, uses tools, checks the result, and keeps going.
01 · The idea
A chatbot answers. An agent acts. Give it a goal like "find three flats in Lisbon under 1,200 euros and put them in a table", and it will search, open pages, compare and write the table.
Agents work in a loop: plan the next step, act with a tool (search, browser, code, email), look at what happened, and repeat until done.
In 2026, many assistants have agent modes that browse the web, write and run code, or work inside your apps. They are useful for research and repetitive tasks, but still make mistakes and can go off track.
Keep a human in charge of anything that spends money, sends messages or deletes things. Try it below: step through an agent's loop.
02 · Think of it like this
A chatbot is like asking a friend for directions. An agent is like giving the friend your car keys and asking them to pick up the groceries.
03 · Try the toy
Watch an agent work
An agent is an AI that loops: plan, use a tool, look at the result, decide. Step through it with Next.
Goal: Book a table for 4 near the office on Friday.
- Plan
- Act
- Observe
- Decide
04 · Do it now
05 · Quick check
Words in this lesson
See also
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Every connector is a door between the AI and your data, so check who made it, what it can touch and what text it lets in.
L169Under the hood · 2 min
Guardrails on the way in
Input guardrails check what users send before the model sees it, catching private data, abuse and tricks early.
L187Under the hood · 2 min
Browser agents: AI that uses websites for you
A browser agent looks at web pages, decides where to click and type, and repeats until a task is done, a handy trick that is slower and riskier than it looks.
L052Staying safe · 3 min
Prompt injection: hidden orders in the text
Prompt injection is when a web page, email or file contains hidden instructions that an AI reads and follows as if you had written them.