Curio

Privacy Policy

Last updated: 2026-07-14 · Applies to the Curio Chrome extension

The short version: Curio has no backend of its own. Your chapter content, chat history, and performance scores are stored securely encrypted in your browser's local storage so you don't lose your progress, and can be deleted instantly at any time. The only place your content is ever sent is the AI provider you (a parent or teacher) choose and connect with your own API key.

1. What Curio is

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.

2. What data exists, and where it lives

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
Learning progress: each chapter's key concepts with their flashcards, practice scores and next review dates	Encrypted locally in `chrome.storage.local` using AES-GCM-256	Deleting the chapter, "Clear Assessment History", or extension removal
Review reminder list: only the dates reviews are due (no chapter content), used for the toolbar badge	Plaintext in `chrome.storage.local` on this device	Updated with your learning progress; extension removal
Saved books: the readable page text and chapter list of an uploaded book (PDF/EPUB), so other chapters can be opened later	Encrypted locally in `chrome.storage.local` using AES-GCM-256	Removing the book from the library, or extension removal (oldest beyond 10 books are dropped)
Optional parent note about the learner (Settings → "About your child")	Encrypted locally in `chrome.storage.local` using AES-GCM-256; sent to your AI provider as part of the tutor's instructions	Clear the field in Settings, or extension removal

Nothing in the table above is ever sent to a server operated by us, because we do not operate one.

3. What your chosen AI provider sees

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:

OpenAI — Privacy Policy · Terms
Anthropic — Privacy Policy · Terms
Google Gemini — Privacy Policy · Terms
OpenRouter — Privacy Policy · Terms

Where a provider offers a no-training / zero-retention option for API traffic, we recommend it, especially for younger students.

3b. Web search (off by default)

If a grown-up turns on Web search in Settings, a question that the chapter doesn't cover is sent to your chosen AI provider together with an instruction to use that provider's own built-in web search tool (Anthropic web search, OpenAI web search, Google Search grounding, or OpenRouter's web plugin). The search runs on the provider's side under their policies; Curio still contacts no other server. These answers are labelled "From the web — not from your chapter" and list their sources. Providers charge a small fee per search.

3c. Videos, recordings and web pages

Video and audio files are transcribed on this device by a small speech model (Whisper) that runs in your browser; its weights download once from Hugging Face and the recording itself is never uploaded. The resulting transcript is then treated like any other chapter text.

Importing a web page reads only the tab you were on when you clicked the Curio icon, and only when you choose "Import". Curio uses Chrome's activeTab permission for this — it cannot read any other tab or site. Imported pages and transcripts are first checked by your AI provider to make sure they are suitable for a child.

3a. Voice features

Read aloud uses your browser's built-in speech voices; Curio does not send that text anywhere. Voice input is off by default. If a grown-up turns it on in Settings, Chrome's speech recognition sends the recording to Google to turn it into text, under Google's Privacy Policy.

4. One more first-run download

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.

5. Children's privacy

Curio is designed to be set up by a parent or teacher on behalf of a child. The adult provides the AI provider account and API key, sees a plain-language disclosure of what that provider will process, and explicitly consents before the child can use the tutor. We do not knowingly collect personal information from children ourselves — we have no accounts and no server. The child's chapter content and questions are only processed by the AI provider the adult selected, under that adult's account and consent.

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.

6. Security

All communication with your AI provider happens over HTTPS.
Your API key is stored only in chrome.storage.local, never synced across devices, and never logged.
Your active session extracts and assessment records are fully encrypted on disk using industry-standard AES-GCM-256.
The extension requests access only to the specific AI provider domains and the model-weights host — nothing broader.
No remote code execution: the extension runs no dynamically fetched scripts.

7. Your controls

Discard session (Chat header) — deletes the active encrypted session content and chunks from local storage immediately.
Clear Assessment History (Dashboard) — deletes all encrypted quiz score trends and weak topic histories.
Clear key (Settings) — deletes your stored API key immediately.
Clear chapter (Settings) — ends the session, deletes the active session, and returns to Upload.
Remove the extension — deletes all locally stored settings, keys, and progress records.

8. Changes to this policy

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.

9. Contact

Questions about this policy can be directed to the extension's listed support contact on its Chrome Web Store page.