Prompt for AI assistants

Paste this into ChatGPT, Claude, Gemini or any coding assistant, then describe the tool you want. You'll get a single HTML file that works in a browser and as a Kapsula app with real alarms.

How to use

Copy the prompt below and paste it into the chat.
Add one line describing your tool: "A tea timer with 3/5 minute buttons", "A Pomodoro with a daily count", "A medication reminder at 9:00 and 21:00".
Copy the resulting HTML into Kapsula: Add project → paste code → Run. Or save it as an .html file and pick it.

The prompt

Build me a single-file HTML app for Kapsula (kapsula.app) — an Android/iOS app that runs one HTML file as a real app with native alarms. Follow these rules exactly.

OUTPUT: one complete .html file (inline CSS and JS, no external scripts, no build step). Mobile-first layout, large tap targets, dark theme, works offline.

SANDBOX CONSTRAINTS:
- No network requests (fetch/XHR are blocked). No external CDNs. Google Fonts are allowed.
- localStorage, IndexedDB and cookies do NOT persist. Persist ALL state with kapsula.storage and restore it on load.
- The host may recreate the page at any moment (e.g. after a notification tap), so the app must rebuild its UI from stored state on every load.

THE BRIDGE (window.kapsula, all methods return Promises; it is absent in a plain browser — detect it with `const K = window.kapsula || null` and keep the app usable without it):
- K.app.info() -> {name, projectId, platform: 'android'|'ios'|'web', version, lang, limits:{alarms:16}}
- K.notify.schedule({at, title, body}) -> {id}. `at` = epoch ms or Date, must be in the future. Creates a REAL OS alarm that fires even if the app is closed. title <= 120 chars, body <= 300. Max 16 pending alarms per project — call K.notify.cancel() before rescheduling.
- K.notify.cancel(id?) -> cancels one alarm, or all of this project's alarms if no id.
- K.notify.list() -> [{id, at, title, body}]
- K.storage.get(key) -> value | null; K.storage.set(key, value) (any JSON); K.storage.remove(key)
- K.sound.play('beep'|'triple'|'alarm'); K.haptics.vibrate(ms)
- Use the language from K.app.info().lang (or navigator.language) for UI text when it makes sense.

PATTERNS:
- Timers: store the absolute end time (Date.now() + ms) in storage, render the countdown from it; schedule an alarm for that end time. Never rely on setInterval alone.
- Daily reminders: compute the next occurrence (today or tomorrow), schedule it, and after it fires (on next load, if Date.now() > at) schedule the following one.
- Wrap every bridge call in try/catch and show the error message in the UI.
- Keep the code readable and commented; no frameworks.

Now build: [describe your tool here]

Why the prompt matters

Assistants don't know Kapsula's bridge yet. The prompt teaches them the five things that make a page behave like an app: the sandbox rules, where state must live, how alarms are scheduled, the 16-alarm limit, and graceful fallback in a normal browser. Full details: bridge API reference.

Kapsula runs only code you add yourself. Nothing is sent to Kapsula's servers — there are none.