How to write a website brief for an AI builder

Why the brief matters more than the prompt tricks

A model fills every gap you leave with the most common answer it has seen. Leave out the audience and you get a page for everyone, which persuades no one. Leave out your prices and you get invented ones. The fix isn't clever phrasing; it's giving the model the five pieces of information that decide what the site is. Everything else, from layout to colour, is easier to adjust afterwards than to get right by describing it in advance.

The five parts of a brief

Audience: One kind of person, described by their situation: "parents of under-fives in Bristol looking for a weekday nursery", not "families".
The single job: What a visitor should do before leaving: book a slot, send an enquiry, join a list, buy one product. Pick one. A second action can exist, but the page is built around the first.
Pages or sections: What has to be there: services with prices, an about section, opening hours, an FAQ, a contact form. Say whether you want one page or separate pages.
Facts: The details only you know: business name, location, prices, hours, team names, years trading, what makes you different. Facts beat adjectives every time.
Tone: Two or three words with an example: "calm and plain, like a good GP's leaflet" says more than "professional".

A template to fill in

Copy this and replace each bracketed description with your own words. Delete any part that doesn't apply rather than leaving it vague.

Worked example: a clinic

"A booking site for Hollis Physio, a two-room sports injury clinic in Headingley, Leeds. It's for runners and club players who've picked up an injury and want to be seen this week. The main thing visitors should do is book an assessment. It needs services with prices, the two physios with their specialisms, opening hours and an FAQ about what to wear. Facts: initial assessment 45 minutes, follow-ups 30 minutes, open 7am to 8pm weekdays, parking behind the building. Tone: calm, direct, no gym slang. Leave out testimonials until we have real ones."

Worked example: a product waitlist

"A one-page waitlist for Tallyroll, an app that chases unpaid invoices for freelance illustrators. The main action is joining the list with an email address. It needs a headline, three short points on what the app does, and a line saying we'll launch in spring and write monthly. Tone: dry and friendly, like a good accountant. No pricing, no feature grid, no logos."

What to leave out

Pixel instructions. "Make the header 80px with a blue gradient" fights the design system. Describe the feeling you want; adjust details in the editor afterwards.
Every feature you might want one day. A brief listing a shop, a blog, a booking system and a members' area produces a crowded plan. Build the first job well, then add.
Borrowed claims. Don't paste a competitor's copy. The model will paraphrase it, and you'll end up with their promises on your site.
Superlatives. "The best bakery in town" gives the model nothing to work with. "Sourdough baked at 4am, sold out most days by noon" does.

How Anticode uses your brief

In Anticode the brief goes to the Architect, the model that plans the build. It replies first rather than building straight away, asks up to three questions where the answer would change the result (each with suggested answers to tap), and then shows a short plan: the name, the kind of site, its sections, the look and the features. If you include a link, such as your current site, the page is read once and summarised into the brief, which saves retyping your hours and services.

Two things in your brief map directly onto the build. The kind of site (landing page, online store, booking app, dashboard, portfolio, or an interactive app) decides the structure. Must-haves such as a booking calendar, contact form, pricing, reviews or FAQ are added as sections. Tone and audience steer which of the seven design systems fits and how the model writes the words. If the plan comes back wrong, correct the plan rather than building and fixing; the guide to building a website with AI step by step covers the rest of the sequence.

Check your brief before you send it

Could a stranger tell from the brief alone what the business sells and where?
Is there exactly one main action?
Does every section you've listed have real content waiting for it?
Have you given at least three concrete facts (a price, a time, a name, a place)?
Is the tone described with a comparison, not a single adjective?

Limits

A brief can't make the model know things it hasn't been told, and it won't stop the draft from being generic where your facts run out. Anticode builds sites in English only, so write the brief in English. Features it doesn't offer, such as a shopping cart or visitor accounts on published sites, won't appear however clearly you ask; the plan will tell you what it can build instead. For the words themselves, see writing website copy that doesn't sound AI-generated.

Questions people ask

How long should my brief be?

One paragraph of four to eight sentences is usually enough. Longer briefs tend to bury the main action under detail the model then tries to fit onto the page.

Can I just write one sentence?

Yes, and the Architect's questions will fill some gaps. But the facts only you know, like prices and hours, still have to come from you, either in the brief or in your edits afterwards.

Should I describe colours and fonts?

Describe the mood instead. Anticode holds each site to one design system with one font family and one action colour, and you can switch the system or the colour later in the editor.