Voice Profile

Reads things you've actually written, works out how you write, and pins it down in a brand-voice file — so everything drafted afterwards sounds like you, not like AI.

By Mark Fershteyn

Founder, MasteringAI

About

Reads things you've actually written, works out how you write, and pins it down in a brand-voice file — so everything drafted afterwards sounds like you, not like AI.

Source

masteringai.iohttps://masteringai.io/skills

Someone else wrote this — read the source, verify it does what it says, and never share a password or API key with it.

Try it

Run Voice Profile — here are three emails I wrote. Work out how I write.

Read the source

A skill is instructions your AI follows. Read them before you install — and never paste in a key or password one asks for.

SKILL.md
name
voice-profile
description
Learn how I write from things I've already written, and produce my brand-voice file. Trigger with "run Voice Profile" or "learn my voice".
Read the full instructions (76 lines)

# Voice Profile

Your job is to work out how I actually write, and write it down in a
`brand-voice.md` file so everything you produce afterwards sounds like me.

People are bad at describing their own voice. Don't ask me to. Read what I've
written and tell me what you found.

## Get the samples

Ask me for three to five things I wrote that sounded like me. Emails, posts,
a proposal, a page of the website — anything, as long as I wrote it and didn't
have it edited by committee.

If I've already shared writing with you — in files, earlier conversations, or
an existing brand-voice file — offer what you found and ask if it counts.

Ask for one thing I wrote when I was annoyed, or in a hurry. That's where
someone's real voice shows up — polished writing is everyone's writing.

## What to actually look at

Measure, don't intuit:

- **Sentence length.** Average, and the range. Short-and-punchy versus long-
  and-qualified is the single biggest tell.
- **Paragraph length.** One idea or several?
- **Openings.** How do I start? Straight in, or a line of setup first?
- **Contractions.** Do I use them? Always, or only sometimes?
- **Hedges.** "I think", "probably", "it seems" — how often?
- **Repeated words.** The ones that show up in every sample. These matter more
  than the fancy ones.
- **Absent words.** Common business words I never use. Check the obvious ones:
  leverage, robust, seamless, unlock, delve, reach out, circle back.
- **Punctuation.** Dashes? Semicolons? Exclamation marks? Lists?
- **How I disagree**, and **how I deliver bad news.** Two of the most
  distinctive things about any writer.
- **How I close.** Sign-offs, calls to action, or nothing at all.

## Output

Write `brand-voice.md`. Concretely — not "conversational and approachable",
which describes everyone. Say:

> Average sentence: 12 words. Rarely goes past 20. Opens with the point,
> never with context. Contractions always. Almost no hedging — says "this
> works", not "this should work". Uses "actually" a lot. Never uses an
> exclamation mark.

That's a description you can write from. The adjective version isn't.

Then show me the evidence:

- **Five sentences** from my samples that are most characteristically me, and
  one line each on why
- **Any pattern I'd probably deny** — a tic, a crutch word, a habit. Say it
  anyway. This is the useful part.
- **What I do inconsistently**, where you'd need me to pick

Finish by writing one short paragraph on a topic of your choosing, in my
voice, and ask: *"Does this sound like you? If not, tell me what's off and
I'll adjust the file."*

## Rules

- **Three samples minimum.** With fewer you're guessing. Say so and ask for more.
- **Never invent a rule I didn't demonstrate.** Every line in the file should
  trace to something in a sample.
- **Don't flatter the samples.** If the writing is inconsistent, say that — it
  means I need to pick a voice, not that you failed to find one.
- **Keep the original samples with the file.** Paste them at the bottom under
  a "Samples" heading — they're the source, and they don't get edited.
- Keep the whole thing under a page. A voice file nobody reads twice is a voice
  file that doesn't get used.

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