Assisted-by: Claude Opus 5.5 via Claude Code

diff --git a/docs/DESIGN.md b/docs/DESIGN.md
index 4e97a91..f2471b3 100644
--- a/docs/DESIGN.md
+++ b/docs/DESIGN.md
@@ -67,7 +67,15 @@ New messages arrive in Inbox. Other messages in the same thread are unaffected 
 
 There is no Read state. "Alex should read this" is Inbox, assigned to Alex. Alex reads it, then moves it on or unassigns himself.
 
-State lives in Docket's database and, on writable accounts, is mirrored as **labels**: mailboxes under a `Docket/` parent (`Docket/Do`, `Docket/Wait`, `Docket/Watch`). Inbox and Done have no label. JMAP mailbox membership is per message, so labels map directly. Labels sit alongside folders — a message can be in `Receipts` and labeled `Docket/Watch` — so state is visible (and editable) in Mail.app and Fastmail web. On read-only accounts, state is database-only.
+State lives in Docket's database. On writable accounts it is also where the message sits on the mail server:
+
+| Mailboxes | State |
+|---|---|
+| Inbox | Inbox |
+| `Docket/Do`, `Docket/Wait`, or `Docket/Watch` | Do, Wait, or Watch |
+| Neither | Done |
+
+The `Docket/` mailboxes are **labels**. JMAP mailbox membership is per message, so a message can be in `Receipts` and labeled `Docket/Watch` at once, and state is visible (and editable) in Mail.app and Fastmail web. Changing state in Docket moves the message to match: Do, Wait, and Watch take it out of the Inbox and add the label, Done takes it out of both and into Archive, and Inbox puts it back. A message in the Inbox that also has a label takes the label's state. On read-only accounts, state is database-only.
 
 Per-person read tracking lives in the database — `$seen` is shared across clients and can't say who read something. Opening a message in Docket marks it read for that user. Read tracking drives unread marks only; it never changes state or assignees.
 
@@ -82,9 +90,9 @@ Each message has zero or more assignees (me, them, or both). It's a soft signal,
 
 ### Folders and filing
 
-Folders are for filing and are managed by Fastmail (including server-side rules); Docket doesn't derive state from them. Any mailbox outside `Docket/` is a folder. Filing is a Docket action on writable accounts only, separate from state:
+Folders are for filing and are managed by Fastmail (including server-side rules). A folder is any mailbox outside `Docket/` without a JMAP role, so the Inbox, Archive, and other system mailboxes aren't folders. Filing is a Docket action on writable accounts only, separate from state:
 
-- Each message is in one folder (or Inbox/Archive). Filing moves the message out of its current folder into the chosen one; `Docket/` labels are untouched.
+- Each message is in at most one folder. Filing moves the message out of its current folder into the chosen one and leaves the Inbox and `Docket/` labels alone, so it never changes state.
 - Folders are also a filter in Docket views ("Do, in School").
 
 ### Comments
@@ -113,9 +121,9 @@ There is no toolbar and no thread-level action. Each message's state, folder, an
 
 The primary other client is **Mail.app over IMAP**; Fastmail web stays in folders mode. IMAP has no labels, so each `Docket/` mailbox appears as a folder holding its own apparent copy of the message (one message underneath — read state is shared).
 
-- Normal clients can read, file, and reply. In Mail.app, an IMAP move only affects the mailbox being moved out of, so filing Inbox → Receipts keeps the `Docket/` label.
-- Triage works from Mail.app by dragging: Inbox → `Docket/Watch` sets the state and removes it from Inbox; option-drag keeps it in both.
-- Label changes made elsewhere are user actions, and Docket adopts them rather than reverting: a `Docket/` label added sets that state; a state label removed with no replacement → **Done**; a message moved to Trash → **Done**; an Inbox message removed from Inbox → **Done**. Assignees and comments are Docket-only.
+- Normal clients can read, file, and reply. In Mail.app, an IMAP move only affects the mailbox being moved out of, so filing Inbox → Receipts keeps the `Docket/` label. Filing an unlabeled message out of the Inbox makes it Done.
+- Triage works from Mail.app by dragging: Inbox → `Docket/Watch` sets the state and removes it from Inbox; option-drag keeps it in both, and the label still sets the state.
+- Mailbox changes made elsewhere are user actions, and Docket adopts them rather than reverting, reading the new state from the table in [State](#state). Trash is the one exception: a message moved to Trash is **Done** whatever labels it keeps. Assignees and comments are Docket-only.
 - Accepted cost: filed messages with a state appear in two folders in Mail.app (and likely twice in its search). Collapsing the `Docket` parent in the sidebar hides most of it.
 - Changes made elsewhere appear in the thread as "via another client".