What The Margin's Vault does and does not protect

The Vault is for things that should stay off the shared screens and away from every AI. A surprise. A plan you don't want read over your shoulder. A note you would rather the assistant never brought up.

For a secret from someone who shares your workspace, it is the wrong tool. That job belongs to your personal workspace, and the section on encryption below says why.

Here is how it played out for one note.

The note#

Sam turns forty on Saturday, Oct 24. Alex Rivera has a note called "Sam 40", with a guest list, the restaurant's deposit date and a long list of ideas. It lives in the family workspace that Sam, Maya and Leo use every day.

Alex opened the note's menu and chose Move to Vault.

Setting it up first#

The Vault is set up once, in Settings→Your Brain, with a passphrase. Setup also offers a recovery key, shown one time. Alex saved it in a password manager.

The recovery key is optional. If you switch it off at setup and later forget the passphrase, nobody can open the Vault again, us included.

The Vault works on every plan, Free included.

Who sees "Sam 40" now#

While the Vault is locked, the note is hidden on every screen in the workspace. Sam's laptop, Maya's tablet and the kitchen wall display show nothing. So does Alex's own phone, until Alex unlocks it.

The app's built-in AI, Margin Intelligence, can't see it either. Sealed items are never pulled into an answer, so Sam asking "what's happening this month?" gets no hint.

Any outside AI app Alex connects to The Margin never sees it, locked or unlocked. If it asks for the note directly, it is told the note doesn't exist.

The Vault belongs to one person in one workspace. If Sam sets up his own and unlocks it, he sees his sealed things, never Alex's.

The same works for a board, a checklist or a whiteboard.

Opening it#

To add a guest, Alex unlocks the Vault with the passphrase. It stays open for fifteen minutes from that moment. Working in the note doesn't extend it. Lock now closes it early.

Offline, Alex can still unlock the screen and read the note on a train. Margin Intelligence needs a connection before it can see inside again.

What is encrypted#

The Margin keeps a memory of what you write, called the Mind, so it can link related things and answer questions. For a sealed item, the Mind's copy is encrypted with a key made from your passphrase. We don't store the passphrase or that key in readable form.

The note itself is different. It still syncs to the workspace's devices like any other note, and the Vault hides it on screen.

So this is not end-to-end encryption. With end-to-end encryption, the service holding your data could not read it at all. Here, The Margin's servers could technically read the note. What the Vault controls is who sees it in the app and what any AI can reach.

That is why it isn't a lock against people you share the workspace with. For a surprise party it is the right tool. It keeps the plan off every screen in the house and out of the assistant's answers. It was never built to hold out against someone in the household who sets out to get in.

For something a person in the workspace must never read, keep it in a workspace they aren't in. Your personal workspace is one click away in the workspace switcher, and its notes never reach the family's devices.

What else sealing shuts off#

While "Sam 40" is sealed:

• A picture or PDF on it never turns up in search.
• It keeps no new versions, and its older ones stay hidden.
• Nobody can edit it at the same time as Alex.
• It can't be shared by link, and an older link stops showing it.
• It never appears on the wall display.
• A web address in it gets no preview, so the restaurant's site is never contacted on its behalf.
• It stays out of every memory export.

The lighter controls#

Some notes don't need a Vault, only to stay out of The Margin's memory. Hide from memory does that: the note stays in your notes and your own search, and the memory never learns from it. It suits things that aren't secret but are nobody's business. The memory has two more switches like it, covered in the docs below.

A PIN lock is different again. An outside AI learns that a PIN-locked note exists and can match its title, nothing more. A sealed note doesn't exist as far as any outside AI can tell.