Last updated: 2026-07-14 · Applies to the Curio Chrome extension
Curio is a browser extension that turns a photographed, scanned, or typed chapter into a private, age-appropriate AI tutor for that one chapter. It runs entirely in your browser — there is no Curio server, account system, or database.
| Data | Where it lives | When it's deleted |
|---|---|---|
| Uploaded chapter content (photos, text, extracted pages) and Vector database chunks | Encrypted locally in chrome.storage.local using AES-GCM-256 | When manually deleted in the library, discarded in Chat, or automatically pruned to fit the 5-session limit |
| Chat history for the current chapter | Encrypted locally in chrome.storage.local using AES-GCM-256 | When manually deleted in the library, discarded in Chat, or automatically pruned to fit the 5-session limit |
| Settings (age, language, AI provider, model, optional PIN hash) | Plaintext in chrome.storage.local on this device | When cleared in Settings, or the extension is removed |
| Your AI provider API key | Plaintext in chrome.storage.local on this device, never synced | "Clear key" in Settings, or extension removal |
| Progress record: past quiz scores and short topic labels per chapter title | Encrypted locally in chrome.storage.local using AES-GCM-256 | "Clear Assessment History" in the Dashboard, or extension removal |
Nothing in the table above is ever sent to a server operated by us, because we do not operate one.
When you upload a chapter or ask a question, Curio sends the relevant chapter content and your question directly from your browser to the AI provider you selected in Settings — currently OpenAI, Anthropic, Google Gemini, or OpenRouter. We do not see or intercept this traffic; it goes straight from your browser to their API using the key you provided.
Please review your chosen provider's own privacy policy and terms, since their data retention and training practices are set by them, not us:
Where a provider offers a no-training / zero-retention option for API traffic, we recommend it, especially for younger students.
To search your chapter privately, Curio runs a small local "embedding" model in your browser. Its
weights are downloaded once from Hugging Face (huggingface.co) and cached by your
browser — this download contains no data about you or your chapter, only the model file itself.
If you are a parent or teacher, please review the linked provider terms above — some providers set their own age or consent requirements for API use.
chrome.storage.local, never synced across devices, and never logged.If this policy changes, we'll update the "Last updated" date above. Since Curio has no account system, we cannot notify you directly — please check back if you have concerns.
Questions about this policy can be directed to the extension's listed support contact on its Chrome Web Store page.