emails with your brand, written for each customer.
heysteff is the AI platform for customer support and sales over WhatsApp, Instagram, Messenger, Gmail and Shopify; Steff is the AI agent that runs it. Email is still where a good share of repeat purchases closes, but sending the same text to the whole list returns less every year. Here you build the template once and the AI personalises what should change on every send.
Built from blocks, not by writing HTML
You compose the email by combining blocks: header, text, product list, button, image, divider and footer. If you need something the blocks do not cover, there is a custom HTML block for putting in exactly what you want.
Underneath, the template is stored as a data structure rather than a tangle of HTML: the visual editor and the code view are two ways of looking at the same thing. You can move between them without the design degrading along the way.
The AI fills specific slots, it does not write the offer
Inside the template you leave slots for the AI to complete on each send — typically the opening line and the button label. You control everything else: the content, the prices, the links.
That split is deliberate. The AI contributes what keeps the email from reading like a mass template, and you keep control of what cannot go wrong. Nobody wants to find out a model improvised a discount.
What the AI generates cannot break anything
The slots the AI fills accept plain text only: never URLs, never HTML, and what it generates is sanitised before insertion. A model that goes off track has nowhere to put a link and cannot dismantle the layout, because the email structure does not depend on what it writes.
It is the same principle applied across the rest of the platform: the AI contributes language, not permissions.
Opt-out comes solved, not left to you
The footer with the unsubscribe link always renders and cannot be switched off from the editor. On top of that, every send carries the headers that make Gmail show its own "unsubscribe" button above the message, with one-click opt-out — what mailbox providers now expect from anyone sending volume.
The unsubscribe link is signed, so nobody can unsubscribe someone else by tampering with the URL. Rather than leaving you responsible for configuring it right, it comes solved by default.
Frequently asked questions
Does the AI write the whole email?
No, and that is deliberate. You build the email structure from blocks and leave specific slots for the AI to fill — the opening line and the button label, for example. You control everything else: the content, the prices, the links. The AI personalises the tone of each send; it does not improvise the offer.
Can the AI invent a link or break the layout?
No. The slots the AI fills accept plain text only: never URLs, never HTML, and what it generates is sanitised before being inserted into the template. A model that goes off track has nowhere to put a link and cannot dismantle the layout, because the email structure does not depend on what it writes.
How does it comply with email marketing rules?
The footer with the unsubscribe link always renders and cannot be switched off from the editor. On top of that, every send carries the headers that make Gmail show its own “unsubscribe” button above the message, with one-click opt-out. The unsubscribe link is signed, so nobody can unsubscribe someone else by tampering with the URL.
◆ next step
Build your template once and let Steff personalise every send in your brand voice.
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