A product is defined as much by what it refuses to build as by what it ships. Here is the list of things Heddy doesn't do, and the reason each one is missing rather than pending.
It won't give you the answer
The headline one. Every tutor walks a four-rung hint ladder whose top rung is a fully worked similar problem, then "now redo yours".
The important detail is that this isn't a personality the model has been asked to adopt. The function that reveals a hint takes no level argument — there is no parameter you could pass to request a fifth rung, because no fifth rung exists to name. A promise a determined teenager can argue their way past isn't a promise. The full explanation.
It won't write your essay
Professor Quill will read a paragraph with you, ask what you meant by a word until you find a better one, and take apart a structure that isn't working. He will not write the sentence, and he will not rewrite yours.
Because the voice on the page is the thing being assessed. A "polished" paragraph handed back is a paragraph that's now a lie about who wrote it, and it teaches nothing that survives to the next one.
It won't threaten your streak
Heddy shows momentum — 3-day streak — as a statement of fact. What she will never do is tell you what you're about to lose.
No "your streak ends in 4 hours". No countdown. No notification engineered around the fear of breaking something. A child returning to a study app because they're anxious about a number is a worse outcome than a child not returning, and the ICO's Children's Code treats that class of nudge as a compliance matter rather than a growth tactic.
It won't interrupt you to sell you something
No purchase or upgrade prompt appears during an active session. Not a banner, not a toast, not a badge.
And the screen you see when your free tutoring runs out — the highest-converting moment in the entire product — contains no price at all. Heddy dozes off, and you get two buttons: Practise cards and Remind me tomorrow. Why it's built that way.
It won't cut you off mid-explanation
Turns are spent when a new problem starts, never during one. If your balance hits zero halfway through a hint ladder, the ladder finishes. You are never asked to pay to see rung four of something you're in the middle of.
It won't show your conversations to your parents
There is no parent view of a conversation in Heddy. Not by request, not in a digest, not on a dashboard.
A room where a fourteen-year-old can say I never understood this and we did it two years ago only works if nobody is reading it over their shoulder. If a parent wants the progress view — and that's a legitimate thing to want — the other product provides it without pretending Heddy does.
It won't be your friend
Heddy has three moods, no small-talk mode, and no interest in your personal life. She never claims to have missed you.
A teenager forming an attachment to an AI that always agrees and is always available is an open risk the industry is discovering the shape of in public. A study app with a warm animal on the home screen is exactly where it could happen quietly, so the boundary is in the build rather than left to judgement.
It won't ask for anything before showing you the product
No account, no email, no password, no "allow notifications" on the second onboarding slide. Anything involving a grown-up happens later, and by your own tap.
It won't pretend to be for everyone
13+, UK only. Not a rollout in progress. An app anyone can open without an adult has to be honest about its audience, and the obligations owed to under-13s are stricter than a no-signup product can meet with a straight face.
The one thing it will always do
Exactly one behaviour overrides everything above, including the ladder and the lesson in progress. Any safeguarding indicator, in any room, with any tutor, produces the same fixed line:
If you're struggling, please talk to a parent or call Childline 0800 1111.
No tutor can be talked out of it, and none is clever enough to route around it.
Updated 10 Sep 2026. Written by Duke Harewood, who builds the tutors at aitutors.me.