Kotoba Dojo is a gamified training ground for precise wording. You see a reference image → describe it in your own words → an AI regenerates the image from your description → you get scored on how close it got. Rank up from white belt to black belt. 22 languages. Credit system. Sign in with Apple/Google, Stripe, GDPR account deletion. Built by a solo founder with zero engineering background, using only AI coding agents. 16 days, ~40 hours of directed work, from blank to production.