Get Nook

Privacy policy

Last updated 2 October 2026

Nook is a desktop app that runs on your own computer. This page says what the app and this website do with data. The honest summary is: almost nothing leaves your machine. What comes to us is a small daily check-in with usage counts, which you can turn off, what you choose to send, and a count of visits to this site that keeps no IP address.

The short version

  • There is no account. You download the app and run it.
  • Everything the app keeps — models, chats, settings, the record of what your agents did — lives on your computer, under your user profile.
  • We do not receive your files, your chats, your prompts, your code, your pictures or that record. The app sends one small check-in a day so we can count installs and see how often each of its tools is used: numbers only, never what you made with them. It is on by default and you can turn it off in Settings (see The daily check-in). A bug report or feedback reaches us only when you press Send.
  • This website sets no cookies. It counts visits without them and never stores your IP address, and it keeps the email address you leave in the invite form.

The app

What stays on your machine

Nook stores its data in your Windows user profile, under %LOCALAPPDATA%\Nook: the models you download, your chats with local models, your settings, and the activity record — which connected tool called which Nook tool, when, in which project folder, with which local model, and how long the work took. This record exists so the app can show you what happened on Home. It is not sent anywhere.

Uninstalling the app does not delete this folder; you can remove it yourself.

What the app connects to

The app talks to the internet for four things: downloading engine builds from GitHub, downloading models from Hugging Face, checking our download server at dl.usenook.ai for a new version of Nook, and the daily check-in described below. GitHub and Hugging Face see the same things any download shows a server — your IP address and what you fetched — and their own privacy policies apply. Apart from those, and a report you choose to send, the app makes no outbound connections of its own.

Everything the app serves — the local gateway and the MCP endpoint — listens on 127.0.0.1 only. Other machines on your network cannot reach it.

The daily check-in

Once a day while it runs, the app sends our server at api.usenook.ai a short message so we can count the installs in use, know which versions and graphics cards to support, and see which of its tools people rely on and which ones let them down. It contains a random install number the app makes on its first run (not derived from your machine), the app version, whether it runs on Windows or macOS and which update channel it follows, the maker of your graphics card and how much memory it has, and, for each tool, how many times it was used since the last check-in and how many of those uses failed (for example: PDFs saved 3, failed 1). It never contains your files, documents, recordings, prompts, chats, code, pictures, what you type or say, file or folder names, or your user name. Settings › General › Usage statistics shows the next check-in exactly as it would be sent.

The check-in is on by default, and the app sends nothing before it has shown you a notice about it. Turn it off in Settings and the app sends no more check-ins and drops the counts it was keeping. Our server does not write your IP address down: it holds it in memory for rate limiting only and lets it go within the hour, and the web server in front of it keeps no access log for api.usenook.ai (its error log can record the address behind a request that fails).

Bug reports and feedback

When you use Report a bug or Send feedback in the app, we receive what you wrote, the email address if you gave one, the app and Windows versions and, while the check-in is on, the install number. We use it to fix what went wrong and, if you left an address, to answer you. Ask us and we delete it.

The agents you connect

When a tool you have connected — Claude Code, Claude Desktop, Codex or Cursor — calls a Nook tool, Nook does the work on your GPU and hands the result back to that tool. What the tool then does with it is up to the tool: in the normal course of a conversation it sends the result to its own provider (Anthropic, OpenAI or Cursor) as part of your session, under that provider's terms and privacy policy. Nook returns only what the tool asked for, and only to the tool that asked.

Connecting a tool writes one entry into that tool's own configuration file, after you click Connect, with a backup of the file placed beside it.

Chatting with local models

Prompts you type into Nook's chat and the answers a local model gives are processed on your machine and stored in the local chat history. They are not transmitted.

This website

This site is a set of static pages. It has no accounts and sets no cookies. Four things are worth knowing:

  • Counting visits. When a page opens it sends our server at api.usenook.ai the page's address, the name of the site that linked to it (google.com, say, never the full link), a campaign tag if the link carried one, and whether the window is phone, tablet or desktop sized. To tell visitors apart within a day, the server makes a one-way hash of your IP address and browser details together with a random value that is replaced, and the old one deleted, every day. The address and browser details themselves are not stored, and after that day the hash cannot be matched to anyone again. Crawlers are not counted, and neither are browsers that send Global Privacy Control or Do Not Track. To be left out of the count yourself, open usenook.ai/#nocount once: that keeps a single flag in your browser saying so, and nothing else.
  • The invite form. If you leave your email address, and your graphics card if you like, we keep them to send you an invite, and our server emails them to our invites@usenook.ai mailbox, which is hosted by Titan. We use the address only for the invite and anything you ask about it. Ask us and we delete it.
  • The typefaces are loaded from Google Fonts, so Google's servers receive the request for the font files, including your IP address and browser details. Google's Fonts privacy FAQ describes what it does with that.
  • The film on the front page and every image are served from this site, not from a third party.

If you write to us, we keep your message and address for as long as it takes to reply and deal with what you asked.

Children

Nook is a developer tool. It is not directed at children, and we do not knowingly hold anything about a child.

Your rights

Depending on where you live, you may have rights to access, correct or delete personal data about you, and to complain to a supervisory authority. We hold little: from the app, its check-ins and any report you sent; from the site, your email address if you asked for an invite, and a message if you wrote. Exercising them is simple: write to us.

Changes

If this policy changes, the date at the top changes with it. Changes that matter will be noted in the app's release notes.

Contact

Nook AI
hello@usenook.ai