atbridge Compose — AI in the compose window

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atbridge Compose is the AI panel that docks right in Thunderbird’s compose window. Click the @b button in the compose toolbar and the atbridge pane opens beside your draft — with your draft already handed to it as context. Ask the AI of your choice to improve, rewrite, shorten, change the tone, or translate what you’ve written, then Insert or Replace the result back into the message. Everything runs on your machine.

Compose vs. Branded Email

Branded Email is a part of atbridge Compose, not a separate thing. Compose is the whole AI-writing surface in the compose window; Branded Email is one thing it can produce — a polished, on-brand HTML email. Everything else on this page (improve, rewrite, tone, translate) is plain-text writing help.

What you can do

Improve a rough draft

Write the gist, then ask atbridge to make it clear and polished — in one click, without leaving the compose window. Switch the AI provider mid-draft (a cloud model for one pass, a local one for the next).

Rewrite & retone

Shorter. Friendlier. More formal. Ask for the version you need and Replace the draft, or Insert an alternative below it.

Translate

Turn the open draft into another language in place — same layout, your words, translated.

Turn it into a branded email

Hand your content to atbridge Branded Email to render a fully-styled, on-brand HTML email — charts, tables, your theme — from the same window.

One-click draft actions

The panel’s ☰ menu (next to the message box) has a Draft actions section for the open draft: Improve Draft, Make Branded Email, Save as Template and Insert Image. Turned a feature off in Settings → Preferences → Optional features? Its action disappears from this menu.

Draft-as-context, and the two ways to apply a reply

When you open atbridge in the compose window, your current draft becomes the context for the conversation — you don’t paste anything. Ask “tighten this and make the ask clearer” and the reply is about your email.

Every reply carries two buttons. They do very different things, and the difference is worth knowing before you press one.

Replace Draft — mechanical, predictable

The reply you just read is written into your draft as-is; only Markdown is converted into real formatting. No further AI step runs, which is why the result is exactly what you saw in the panel.

Blend into email — a second AI step, on purpose

Use this when you have already written something yourself and want the assistant’s point folded into it, instead of a second email pasted on top.

To do that atbridge sends the model your current draft plus the reply as an instruction, and applies what comes back. Which of two routes runs is decided automatically from what your draft contains — there is no toggle:

• Your draft is plain typed text → the model returns only a short new passage (usually 1–3 sentences, matched to your tone and language) and the place it belongs. Everything you already wrote stays exactly as it is, character for character. Note that the inserted passage is newly written, so it will not be word-for-word the reply you read in the panel.
• Your draft already contains formatting (a table, headings, a bullet list, a coloured band) → the email is rebuilt as one designed branded email with your change woven in. Here the whole email is rewritten and re-laid out, and it counts as one Branded Email against your plan.

You can tell which one is running from the progress message: “Designing your branded email…” is the branded route, “Preparing email draft…” is the plain one.

In both routes the quoted original of a reply or forward, and your signature, are put back untouched.

Which one do I want?

Use Replace Draft when you want the text you just read, verbatim. Use Blend into email when the draft is already yours and the assistant’s point needs to land inside it.

The compose pane runs ephemeral sessions with the AI of your choice — any provider, or a private local model via Ollama. It can also reach your knowledge base while drafting: atbridge Notes, other emails, and your own OpenAI Vector Store.

Branded Email — one of its outputs

The headline capability of Compose is Branded Email: describe what you need (“invoice Example Bakery for analytics onboarding and dashboard setup”) and atbridge renders a polished, on-brand HTML email — your AI writes the content, atbridge builds the email-safe HTML.

atbridge Branded Email → AI-designed, on-brand HTML emails — invoices, newsletters, proposals and more. The full guide + every template.

Where else it runs

Compose lives in the Thunderbird compose window, but the same rendering is available everywhere atbridge runs — the atbridge AI Chat, over MCP, and from the CLI (atbridge compose …). See the CLI reference for the compose commands.