Keeping your brand voice when AI drafts
Give the model a voice it can follow, examples it can match, and a review that catches the drift.
Ask a model for a product description and you get competent, friendly, slightly excitable copy. Ask again for a different brand and you get much the same thing. Left alone, AI drafts drift towards an average voice that belongs to nobody.
If your brand has a way of speaking, the model can follow it. It needs more than “make it sound like us”. It needs the voice written down in a form it can act on.
Describe the voice in terms you can check
Words such as “warm”, “bold” and “human” appear in most brand guidelines and tell a writer very little. Describe choices instead. Nielsen Norman Group’s four dimensions of tone of voice are a useful starting point: funny or serious, formal or casual, respectful or irreverent, enthusiastic or matter-of-fact. Decide where you sit on each one.
Then add rules a reviewer could tick off. Sentence length. Whether you use contractions. Whether you speak as “we”. How you handle numbers, prices and technical terms.
Show the voice with real examples
Models match examples more reliably than they follow adjectives. Collect five to ten short pieces of your own writing that you consider right: a product description, an email, an error message, a social post. Label each with what it is for.
Pairs work especially well. For a fictional bicycle repair shop, a pair might look like this:
- Not us: “We’re passionate about delivering world-class cycling solutions for every rider’s journey.”
- Us: “We fix bikes. Most repairs are done the same day. If yours will take longer, we say so before we start.”
The second version shows short sentences, plain verbs and a specific promise. The model can copy that pattern. It cannot copy “authentic”.
Keep a list of words you do and do not use
Every brand has vocabulary. The shop above says “repair”, not “service solution”; “bike”, not “cycle”; “today”, not “same-day turnaround”. Write two short lists: preferred terms, and terms to avoid. Include the stock phrases that mark copy as generic, so the model is told not to reach for them.
Put it all in one reusable brief
Combine the description, the examples and the word lists into a single voice brief. Use it at the start of every writing task, or save it wherever your tool keeps standing instructions. Everyone on the team should use the same version.
Then give each task its own details: who the reader is, what they need to know, what they should do next, and how long the piece should be. Voice tells the model how to speak. The task brief tells it what to say.
Supply the facts yourself
A model asked for persuasive copy will supply persuasive details, whether or not they are true. Give it the prices, opening hours, materials and guarantees you want mentioned, and tell it to use nothing else. Treat any claim you did not provide as an error to remove, however well it reads.
Review for drift, not just for mistakes
A draft can be accurate and still not sound like you. Read it aloud and check it against the brief:
- Voice: does it sit where you decided on each tone dimension?
- Vocabulary: are any avoided words present?
- Specifics: is every fact one you supplied?
- Padding: can any sentence go without losing meaning?
- Ending: does it stop when it has said what it needs to?
When you correct a draft, note what you changed. If the same correction keeps appearing, the brief is missing a rule. Add it, and the next draft starts closer.
Decide what a person always writes
Some writing carries more weight than a draft should bear: an apology, a reply to a complaint, a statement about a mistake. Decide in advance which pieces a person writes from the start, and which a person approves before they go out. Voice consistency matters less than judgement in those moments.
A voice the model can follow is a voice you have written down.
The work of defining the voice is useful with or without AI. New team members and freelancers benefit from the same brief. The model simply makes the gap obvious sooner, because it will fill any silence with the average.
Sources and further reading
Tone framework: Nielsen Norman Group: The four dimensions of tone of voice, checked on 10 November 2026. The bicycle shop and its copy are fictional examples, not reported client work.