Not files, not folders, not a permission model you have to learn. Whole parts of a life, switched on per person — and everything starts shared with nobody until you say otherwise.
Giving someone access is not giving them authority. A seat is not an account, not a login, and not a copy — it is permission to ask a question, and nothing else in the product will answer to it.
A lock is a fact about you that you did not mean to disclose. It tells them something is there.
Marcus is never told there is more. There is no greyed row, no count of what he cannot reach, and no way to work out what he is missing.
Every answer they get carries the document behind it. Every time they come, you see it — what they asked, what opened, and when.
She cannot browse, cannot list what exists, and cannot tell an empty answer from an absent one. You can read all of it.
One link, sent once. It becomes theirs and cannot be forwarded into working for someone else. Close it and the next question returns nothing — not a warning, not a cached answer, nothing.
A copy cannot be taken back. That is the entire reason this is a seat.
Give a seat to an assistant the same way you give one to a person — the same parts of your life, the same log of every question. The difference is what it can do with one.
Every other product waits for an event before it lets anyone in: a certificate, a form, a timer that has to run out. A seat is already working, so there is nothing to wait for and nothing to produce.
A seat your children keep. Every answer is something you wrote — a message you sent, or a note you sat down and left on purpose.