Supermail Email Plain Speak

What it is

Plain Speak is the reading shortcut next to Catch me up. Where Catch me up summarizes a thread in two paragraphs, Plain Speak answers the question a busy reader actually has: "Do I need to do anything, and by when?" — in one glance.

The card carries five things:

• TLDR — one or two short sentences on what the thread is about.
• What they want — what the sender asks of you, or nothing.
• Deadline — any date or deadline the email states, exactly as written.
• Next step — exactly one of Reply, Archive, Schedule or Ignore.
• Heads up — one short line, only when something is genuinely notable.

Where to find it

Open any email thread in Supermail. A small arrow-swap button sits in the thread toolbar next to Catch me up (only when the feature is turned on). Click it — or press v — to flip to the card; click it again, press v, or choose Show original email to go back.

It is in development and off by default — hidden until you turn it on in Settings → Features (the Plain Speak toggle). When it is off, nothing runs and no button appears.

How it behaves

• It never slows down opening mail. The card is written in the background, after the conversation is already on screen. While it is being written the button shows a quiet spinner.
• It never pays twice for the same thread. A finished card is remembered for that thread and its newest message. Re-opening the same thread costs nothing, and a new message produces a fresh card.
• It is cost-capped. Plain Speak has its own daily spend limit in the app. At the limit, the card says the limit was reached rather than failing vaguely.
• It fails honestly. If the AI cannot answer, the card says so in plain words: a connection, rate-limit or key problem is named as that, and an unusable answer says it could not summarize this email right now. A provider problem is never remembered, so opening the thread again tries again instead of staying broken. Those failures are counted, so a broken path is visible in the app's usage report instead of looking like nobody uses the feature.
• It uses the AI model you already chose. Plain Speak uses the same Summary model setting as Catch me up (Settings → Supermail), with the same cheap default and the same automatic Claude backup.
• Its wording follows the email. The card is written in the language of the thread.
• Where your email goes. Writing the card sends the thread's text to the app's AI providers — the same destination Catch me up already uses, under the same protections. It runs only after you turn it on, and the feature's Settings description says so plainly.
• Desktop only. On a phone the button does not appear, because this path spends AI credit and carries full email bodies.
• Read-only. Plain Speak reads the thread and suggests a next step; it never replies, archives or changes anything for you.
• One click back. The card never hides the email — the toggle and Show original email both return you to the conversation.

Related

• Supermail AI Summary ("Catch me up") — the two-paragraph summary of a thread.
• Supermail AI Filtering — decides what to do with new mail.
• Supermail Assistants — opens a working conversation from a thread.