You have already trained a model and used it inside a program. Today the question is different: what happens when software is given a goal and allowed to plan, use tools, and act in a loop until the job is done?
That kind of software is called an AI agent. You will direct one on the board, then take turns being the agent yourselves.
A chatbot answers. You ask a question, it replies with text. The conversation stops until you type again.
An AI agent is a model given a goal. It works through four phases:
| Phase | What the agent does |
|---|---|
| Plan | It plans the steps needed to reach the goal. |
| Act | It uses tools: it writes a file, runs code, searches or sends a message. |
| Observe | It looks at what happened: an error message, a result or a web page. |
| Adjust | It adjusts the plan and tries the next step. |
It keeps looping through plan, act, observe, adjust until the goal is met or it is stopped. A chatbot waits; an agent keeps going.
Your class is about to direct an AI coding agent. One person is the error-spotter: their job is to call out when something looks wrong. Everyone else confirms the goal, predicts the next step before it happens, and names which phase is running: plan, act, observe, or adjust.
Write a short program that asks for two numbers and prints their sum. If anything breaks, fix it.
Your teacher will run a live agent on the board, or walk through a worked example one move at a time. Before each new move is shown, write or say: next phase = ? next action = ?
The worked example
Show move 1
Plan. The agent says: "I will write a short program that asks for two numbers, adds them, and shows the total."
Predict: what tool will it use first?
Show move 2
Act. The agent writes this program:
a = input("First number: ")
b = input("Second number: ")
print(a + b)Predict: what will it print when someone types 3 and then 4?
Show move 3
Observe. It runs. The output is 34, not 7.
Error-spotter: what went wrong?
Show move 4
Adjust. The agent says: "The inputs were treated as text, so + joined them together. I need to convert them to whole numbers first."
Predict: what will it change in the program?
Show move 5
Act again. The agent changes the program and runs it with 3 and 4:
a = int(input("First number: "))
b = int(input("Second number: "))
print(a + b)Predict: what will it print now, and what will the agent do after that?
Show move 6
Observe. The output is 7. The goal is met, so the agent stops.
After the run, answer as a class:
- Which steps were plan, act, observe, adjust?
- Where did the agent need a human watching it?
- How is this different from a chatbot that only explains how to add two numbers?
- Observe and adjust is debugging: the agent runs a test, reads what went wrong, and fixes it. Where did you see that today?
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