Brilliant's new AI tutor refuses to give you the answers

Most students use AI as an overqualified homework-copying machine: paste the problem into a chat box, copy the result, and move on.

That creates a quiet disaster for learning. Every time an algorithm hands a kid a solution, it steals an opportunity to actually think.

Interactive learning platform Brilliant rolled out Koji, dubbing it the world's first graphical tutor. Its core rule is simple: it flat-out refuses to give you the answer.

It watches where you hesitate and draws on your screen

Trained alongside learning experts from MIT and Harvard, Koji is built directly into Brilliant's visual, hands-on lessons.

Instead of sitting in a separate sidebar chatting away in text, Koji can see your screen in real time. If you are dragging tangent lines to understand derivatives, it notices your wrong guesses and flags the exact moments you freeze up to guess why you are stuck.

From there, Koji does not drop paragraphs of explanation. It reaches directly into the interactive canvas: highlighting a specific coordinate, scribbling annotations over a graph, or throwing in an intermediate micro-puzzle to nudge your intuition.

Brilliant also made Koji speak first by default. Testing showed waiting for students to raise their hand created friction, but having the tutor casually point out what changed from the previous problem dramatically lowered the barrier to engage.

The team even tried killing off the mascot character in favor of a sleek, modern sparkle icon. Students hated that. As 10-year-old Arthur noted, most kids just use AI to cheat on homework, but having an actual character watching makes you want to try harder.

Koji is already live across most math and coding courses on Brilliant with multilingual speech support, with personalized school assignment tutoring slated next.

Why it matters

We think Brilliant nailed what everyone else has been getting wrong about AI in education.

Slapping a chatbot wrapper on an LLM just turns AI into a shortcut machine. Students feel like they understand because they read a clean explanation, but the knowledge evaporates five minutes later. Koji treats real learning as a struggle, using AI to provide handholds rather than an escalator.

This also showcases a serious moat for Brilliant. You cannot build a graphical tutor like this on top of static PDFs. It requires years of modular, interactive code blocks that a model can read, manipulate, and annotate on the fly.

The real test will come when Brilliant expands Koji beyond its tightly controlled in-house curriculum into messy, real-world school homework. But right now, showing the restraint to withhold answers makes Koji one of the smartest agentic designs we have seen.