Shipped · Zero Gravity · 2026
Built an AI tutor that coaches instead of answering
Students without a tutor at home get stuck alone, and a general chatbot just gives them the answer.
- Coaching, practice, marking and assignments as separate agents, each graded by its own evaluator, across Maths, Physics, Chemistry and Biology for AQA, Edexcel, OCR and IB.
- Red-teamed the failure that matters most: a student talking the tutor into handing over the answer. Then a pass/fail judge on every session.
- A four-agent fleet read every production trace overnight, replaced a planned ops hire and produced half the evidence in the company retro.
- 30 → 850+
- schools, from the beta to the national programme
- 67% → 99%+
- marking on the golden set: bare model, then the syllabus we covered
- 33% → 65%
- Socratic pass rate, doubled in two weeks, graded on every session
- 50,000+
- tutoring sessions
What we learned When production ran 4.6x over the cost plan, we cut it without touching quality: prompt caching, a model per task, and Opus kept on marking. Next, the Pioneers pilot measures what it does for pupils' grades.
My part Led product, a designer and six product engineers, each owning a problem from prototype to production, and wrote 28% of the commitsview the product ↗App Store ↗
