Why this matters
As a Prompt Engineer, you often adapt large language models to speak in a specific brand voice. Real tasks include drafting product announcements in a consistent tone, rewriting customer support replies to match empathy and clarity standards, and creating templates so any team member can generate on-brand content quickly.
Who this is for
- Prompt Engineers and ML practitioners who need to align outputs to a brand or organization.
- Writers and PMs who want reliable, on-brand drafts from LLMs.
- Support and marketing teams adopting AI-assisted authoring.
Prerequisites
- Basic prompting (system and user roles, constraints).
- Familiarity with target audience and brand values.
- Ability to review outputs critically for tone, clarity, and compliance.
Learning path
- Understand brand voice components.
- Build a reusable style kit prompt.
- Practice with worked examples and constraints.
- Add evaluation rubrics and iterate.
- Ship a small project and collect feedback.
Concept explained simply
Brand voice is how a brand sounds: the tone, word choice, structure, and guardrails that make content feel consistently "us".
Mental model
Voice = Tone + Diction + Structure + Constraints + Principles
- Tone: friendly, formal, playful, empathetic, etc.
- Diction: simple vs. technical words; regional spelling.
- Structure: sentence length, headings, bullets.
- Constraints: length, banned terms, required phrases.
- Principles: values like honesty, helpfulness, inclusion.
Compact "Voice Kit" you can reuse
- Audience & context: who, channel, goal.
- Tone sliders: warmth (low/high), energy (low/high), formality (low/high).
- Diction: grade level, jargon allowed/avoided, regional spelling.
- Structure: format (bullets, email, post), sentence length, headline rules.
- Constraints: must-include phrases, banned claims/words, length limits.
- Brand principles: e.g., respectful, transparent, helpful.
Worked examples
Example 1: Formal B2B email announcement
Prompt (system extract)
Role: Write in B2B formal tone. European spelling. Clarity first. Avoid hype. No emojis. Audience: IT managers. Constraints: 150-180 words. Include subject line. Avoid "revolutionary"/"disrupt". Goal: Announce maintenance window and expected impact.
Generic output (contrast)
We are thrilled to share an awesome update! Our platform will be down briefly but it's nothing to worry about.
Brand-aligned output
Subject: Planned maintenance on Saturday, 03:00–05:00 CET We will perform scheduled maintenance to improve stability. Services may be intermittently unavailable during this window. What to expect: - Impact: brief API interruptions - Window: 03:00–05:00 CET (Saturday) - No action required from your team We will monitor closely and restore normal service as soon as work is complete. If you have questions, reply to this email and our support team will assist. Thank you for your understanding.
Example 2: Playful mobile push notification
Prompt (system extract)
Channel: push notification. Tone: playful, concise. Limit: max 120 characters. Include one emoji. CTA: "Open app".
Brand-aligned output
Your weekly stats are in—spoiler: you crushed it! 🚀 Open app to see the wins.
Example 3: Empathetic support reply
Prompt (system extract)
Role: Support agent. Tone: calm, empathetic, solution-focused. Avoid blame. Steps: acknowledge, explain, give fix. Constraints: 90–140 words. No emojis.
Brand-aligned output
Thanks for reaching out—sorry for the frustration with failed uploads. A recent update caused larger files to time out. Here’s a quick fix: 1) Try the web uploader (it handles bigger files). 2) If you prefer the app, update to v3.2.1 and retry. We’re also increasing the timeout in our next release. If it still fails, reply with the file size and timestamp and we’ll investigate.
Example 4: Blog intro with clear structure
Prompt (system extract)
Format: blog intro (120–160 words), subhead, short paragraphs. Tone: confident, non-hype. Reading level: grade 8–9.
Brand-aligned output
Subhead: Ship features faster without losing sleep Speed matters. But rushing features too often means late nights and brittle launches. There’s a better path. In this guide, you’ll learn a simple release checklist teams use to move quickly and cut risk. It takes minutes to run and saves hours of rework. Let’s walk through it step by step.
How to build a brand voice prompt
- Capture principles: Write 3–5 short brand statements (e.g., "honest, helpful, inclusive").
- Specify audience and channel: Who reads it and where it appears.
- Set tone sliders: Warmth, energy, formality.
- Control diction: Reading grade, jargon allowed/avoided, regional spelling.
- Define structure and length: Bullets vs. prose, headings, word/character limits.
- Add constraints: Must-include phrases, banned claims, compliance notes.
- Require a self-check: Ask the model to verify alignment before final output.
Reusable template
System: You write in our brand voice. Principles: [list 3–5]. Tone: warmth [low/med/high], energy [low/med/high], formality [low/med/high]. Diction: grade [x], [US/UK] spelling, [jargon allowed/avoid: ...]. Structure: [format], [length], [headings/bullets]. Constraints: must include [...]; avoid [...]; claims must be verifiable. Audience & channel: [who], [where]. Self-check: Before final, list 3 bullets showing how output matches the voice, then provide the final text.
Checklists and quick wins
- Audience and goal are stated first.
- One clear tone description (avoid stacking conflicting traits).
- Reading level fits audience.
- Specific length and format constraints.
- At least one "avoid" or banned-term rule.
- Ask for a brief self-check before final text.
Evaluation rubric (score 0–2 each)
- Tone fit (0=off, 1=mixed, 2=on-brand)
- Clarity (0=confusing, 1=ok, 2=crisp)
- Diction (0=wrong jargon/spelling, 1=minor slips, 2=consistent)
- Structure (0=unreadable, 1=partly structured, 2=well formatted)
- Compliance/honesty (0=overclaims, 1=borderline, 2=accurate)
Evaluate and iterate
Run the rubric, note the lowest score, and tighten the prompt there. For example, if tone is weak, add examples or stronger constraints (e.g., "avoid hype words: revolutionary, disrupt").
Common mistakes and how to self-check
- Vague tone labels ("professional"): replace with sliders (formality: high, warmth: medium).
- No audience specified: add who and where (e.g., "IT managers via email").
- Length drift: add explicit limits and ask model to count words/characters.
- Hype or overclaims: include banned terms and require verifiable claims.
- Conflicting instructions: remove contradictions ("formal" and "use emojis"). Choose one.
- One-shot prompts only: prefer a short style kit + self-check step.
Exercises
Exercise 1: Rewrite into brand voice
Goal: Turn a generic paragraph into on-brand copy for a B2B landing page hero.
- Set brand voice: formal, warm, UK spelling, grade 9, no hype.
- Audience: engineering leaders. Channel: website hero section.
- Constraints: headline (max 7 words), subhead (15–25 words), avoid "revolutionary", "disrupt".
- Rewrite this text: "Our tool is a game-changer that will transform your workflow instantly."
Sample solution
Headline: Reliable releases, fewer late nights Subhead: Plan, test, and ship with a simple checklist that reduces risk and keeps teams moving without burnout.
- Checklist: Did you stay within length limits?
- Checklist: Are banned words avoided?
- Checklist: Tone is formal but warm?
- Checklist: UK spelling if relevant?
Note: Anyone can do the exercises and the test. Progress is saved only if you are logged in.
Practical projects
- Project A: Create a 1-page brand voice kit for your team and test it on three channels (email, push, blog). Acceptance: rubric average ≥ 8/10 across channels.
- Project B: Build a prompt template that outputs a support reply with self-check bullets. Acceptance: three varied tickets produce consistent tone and structure.
- Project C: Assemble a banned-terms list and required phrases for a compliance-sensitive product. Acceptance: zero violations across 10 generated samples.
Mini challenge
In two sentences, explain your brand voice to a new teammate using the formula: Tone + Diction + Structure + Constraints + Principles. Then create a 60-word example that matches it.
Next steps
- Convert your best prompts into reusable templates.
- Add self-check steps to all style prompts.
- Collect examples of on-brand and off-brand outputs to refine constraints.
- Take the quick test below to confirm you can diagnose and fix voice issues.