How a marketing team keeps AI writing in one brand voice

What the guide holds

A worked example

Illustration: a made-up business. Ridgeway, an outdoor-gear shop, has a four-person marketing team, and each person's AI writes differently: one adds exclamation marks, another opens with "unleash your next adventure". The content lead gives the brand-voice skill ten emails and product pages that customers replied to, and gets back a guide. Sentences average 11 words, "you" comes three times as often as "we", there are no exclamation marks, and numbers are numerals. The traits: practical, not preachy (do, from a sample: "Pack it at the top of your bag; it's the first thing you'll need when the rain starts."); warm, not gushing; expert, not technical.

The rewrite keeps every fact and adds none. The writer adds who it's for, and checks both numbers against the spec sheet before it ships; see rules for AI-written marketing claims.

Roll it out

1. Collect ten pieces customers responded to, from more than one writer.
2. Build the guide with numbers and quoted lines, not adjectives.
3. Share it once as a skill everyone's AI reads: on Claude Team or Enterprise, or ChatGPT Business, Enterprise or Edu. Retire the personal prompts.
4. Give it one owner, who changes it when the team agrees.
5. Read five drafts a week and fix the guide, not the writers, when they drift.

Next step: the rest of the marketing skills

A voice skill is the base the other marketing skills read from. Claude skills for marketing covers the next ones to set up. For a support team's replies, the same method is in making your support team's AI replies sound like you.

Questions

How do I keep AI writing in our brand voice?

Give every writer's AI the same short voice guide built from your best real samples, not from adjectives: measured patterns (sentence length, "you" against "we", exclamation marks), three or four "this, not that" traits each proved with a quoted line, a word list and the mechanics. Share it as a skill so everyone's AI reads one version, and give it one owner.

What goes in a brand voice guide for AI?

Patterns with numbers from your samples; where you sit on Nielsen Norman Group's four tone dimensions; three or four traits as "this, not that" pairs, each with a do quoted from a sample and a don't; the words you use and avoid; the mechanics the samples settle, such as headline case and numerals; and how the tone shifts for bad news.

Can a voice guide fix weak copy?

No. Voice changes wording, order and length, not substance. If a draft has no proof, no clear offer or no reader, the guide should say so instead of polishing it, and claims still need checking against the evidence before anything ships.