How AI works. Not read about. Done with your own hands.
Each lesson takes one idea that is genuinely hard, explains it in plain words, then puts the real thing in front of you to operate: a model picking its next word, attention lighting up across a sentence, a reward signal shaping a personality, an agent reading a poisoned email. Where you see numbers, they come from a real model.
Start with lesson 01- 01How ChatGPT Works: It Predicts the Next Word
- 02Transformers Explained: How AI Decides Which Words Matter
- 03How ChatGPT Is Trained: RLHF and Why It Agrees With You
- 04AI Hallucination Explained: Why ChatGPT Makes Things Up
- 05Context Window Explained: Why ChatGPT Forgets
- 06AI Agents Explained: How They Work and Why They Fail
How does ChatGPT work? It guesses the next word, one token at a time
Operate a real model's next-word choice: see its odds, turn the temperature, roll the dice.
How does a transformer know which words matter? Attention, shown for real
Hover a word and see where a real model looks. Find the head that links 'she' to 'sister'.
How are ChatGPT and Claude actually trained? Pretraining, human feedback, and why they are so polite
Be the human in human feedback. Rank answers, watch the model learn to please you, catch sycophancy being born.
Why does AI hallucinate? Why ChatGPT is confidently wrong and can't say 'I don't know'
Play the calibration game: 12 questions, your confidence, your curve next to GPT-4's.
Why does ChatGPT forget? The context window, explained simply
Fill a context window with your own messages and a pasted PDF, and watch the beginning fall off.
What is an AI agent, really? The plan, act, observe loop, tools, and the ways agents go wrong
Run an agent on a fake inbox. One email is poisoned. Choose the permission mode and see what happens.
Real numbers, or we say it's a simulation.
Where a lab shows probabilities or attention, they come from a real open model (GPT-2) run once and saved into the page. Where a lab is a simulation, like the reward game or the agent inbox, it says so on the lab, and the text explains how the real thing differs.
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