The bar you want to fill

With the Firestore optimization shipped, the design question becomes pricing display, and the answer is elegant because it’s true. Severo will charge by tokens consumed, which is to say by how much of the teacher’s memory, “la RAM de la IA”, la ventana de contexto ▸ 4:44, your learning has filled. So the UI is a single bar that rises as you study, modeled on AI Studio’s own token counter ▸ 6:12, with tier lines drawn at the thresholds: reach one and the app offers the next plan, or free up memory ▸ 6:30.

He calls it “un arma de doble propósito” ▸ 5:08. Purpose one is transparency: the user sees exactly the resource they’re consuming, no mystery meter, just the real quantity with the jargon removed (“obviamente no les vamos a decir que es tokens”). Purpose two is psychology: “a la gente le gusta completar las cosas” ▸ 6:56, so the same line that meters billing also whispers what happens when I fill it?, converting the paywall’s approach into a tiny motivation to study more.

el mejor medidor de cobro es el recurso real, dibujado bonito →

It’s a neat inversion of the dark-pattern economy they were dreading a day earlier: the manipulative version of this bar would decouple from reality and fill whenever the business wanted money. This one can’t lie without breaking, because it is the database counter, the aggregate document built two days ago finally wearing clothes. When the honest number and the engaging widget are the same object, pricing stops needing persuasion…