---
description: Turn 3-5 real samples of your content (posts, emails, site pages, past articles) into a reusable brand-voice.md file. Extracts your voice across 6 dimensions and outputs a short, actionable file you paste into a CLAUDE.md or reference from any prompt. Use when your copy still sounds generic even though you re-paste your rules every time. Upstream companion of writing-unslop: unslop cleans one piece, brand-voice defines the permanent template. Sibling of setup-claude-md on the context side.
allowed-tools: Read, Write, Glob, Grep, WebFetch
argument-hint: "<paths or pasted samples of your real content> (optional)"
---

# Brand Voice — Freeze your voice into a reusable file

Take real samples of what you have already published and distill them into a `brand-voice.md`: a short, actionable file that carries your voice by example, ready to paste into a CLAUDE.md or reference from any prompt or Skill. This is the concrete artifact behind the idea "show your voice, don't describe it": the model generalizes better from examples than from a list of adjectives.

The output is not a brand book. It is one page the AI loads so its first draft sounds like you, without you re-pasting your rules every time.

## When to use

- Your copy sounds generic even though you re-paste your tone, your banned words, and two examples in every conversation.
- Your voice lives in your head and in a Google Doc nobody reopens, never next to the output.
- You want the permanent template, not a one-off brief. A brief frames one task and dies with it; the voice file does not change from one task to the next.

Where this sits among the neighbors:
- **Upstream of `writing-unslop`.** Unslop is a filter that cleans a single piece after the fact. Brand-voice defines the template once, so drafts start closer to right. Use brand-voice to set the mold, unslop to scrub each output.
- **Sibling of `setup-claude-md`.** Both produce a permanent context file. `setup-claude-md` covers who you are, your stack, your hard rules. This one covers only how your brand sounds, and can live inside a CLAUDE.md or on its own.

## Input

Samples of your real, published content, in any of these forms:
- Pasted directly as the argument
- File paths or a folder to read (`Glob`/`Grep` over past articles, drafts, exports)
- A URL to fetch (a live site page, a newsletter archive)

Ask for 3 to 5 pieces you are proud of, across the channels that matter (a post, an email, a site page, an old article). If the user gives fewer than 3, ask for more: two samples are not enough to separate voice from accident.

## Workflow

### Phase 1 — Gather the samples

Collect or read the 3 to 5 pieces. Prefer content the user has corrected until it sounded right: that is where the voice is sharpest. If a project has a CLAUDE.md or an existing brand doc, skim it too, but treat the samples as the source of truth. You deduce voice from what exists; you never invent it.

### Phase 2 — Extract the six dimensions

Read across the samples and pull out what is constant, not what appears once. For each dimension, quote the sample line that proves it: the file must show, not assert.

1. **Register and address.** Formal or casual, `tu` or `vous`, first person singular or plural. Set a formality cursor per channel when it varies (a LinkedIn post and a legal page do not speak alike). Note the cursor as a number out of 10 per channel.
2. **Sentence rhythm.** Short punches, long explanatory sentences, or a deliberate mix. Fragments allowed or not. Typical paragraph length. This is what makes copy feel like a person, and it is invisible in a list of adjectives.
3. **Signature lexicon and banned words.** The words the brand actually uses (quote real ones from the samples) and the words it never uses. Write the banned list in caps as `NEVER ...`: default model mistakes are predictable ("Nous sommes ravis de", "solution", "innovant"), and caps signal priority.
4. **Recurring figures.** The moves that repeat: analogies, headline formats, opening hooks, the way lists or callouts are built, a signature closing. Name the pattern and give one instance.
5. **Stances.** What the brand asserts and what it refuses. The opinions it takes, the claims it will not make, the tone it rejects (no hype, no corporate-therapist voice, no unquantified superlative).
6. **Do and don't, shown by pairs.** Three to five before/after pairs pulled from the real samples: a first draft and its corrected version. The pair carries the movement no instruction can transmit. This is the most important block.

### Phase 3 — Write brand-voice.md

Turn the six dimensions into one page. Structure with `#` titles and `-` bullets, banned words in caps, before/after pairs at the end. Dense, no filler, no brand-story. Every line must change a sentence the AI would write; if it does not, cut it. Keep it to one screen: the useful rules must not drown in narrative.

Hand the file back in a copyable block, and tell the user where to put it: a CLAUDE.md for Claude Code, a Project or account instructions for Claude, custom instructions for ChatGPT. One file, pasted where it persists, replayed on every output.

### Phase 4 — Non-regression test

Prove the file works before shipping it. Open the mental equivalent of a blank session: pick a real task the user does often (a launch post, an email), and regenerate a short excerpt using only `brand-voice.md` as context, nothing re-pasted. Read it against the samples: does it sound like the brand at the right register? If it drifts, trace the miss back to a weak dimension (usually a described rule that should be a shown pair) and tighten that block. Re-run until the excerpt sounds right, then the file is done.

## Output example

```markdown
# Brand voice: Facturo

## Register and address
Tu, never vous. First person "on".
Cursor: LinkedIn 6/10, email 5/10, legal page 9/10.

## Sentence rhythm
Short punches, one idea per sentence.
Fragments allowed for emphasis. Paragraphs of 2-3 lines.

## Lexicon
Use: facture, relance, encaisse, en retard, deux clics, tranquille.
NEVER: "solution", "innovant", "revolutionnaire", "ecosysteme".
NEVER: "Nous sommes ravis de". No unquantified superlative.

## Recurring figures
Hook = a dated scene ("Mardi, 14h."). Close = one-line payoff.

## Stances
We assert: admin should take minutes, not hours.
We refuse: hype, corporate tone, promises without a number.

## Do / don't (before -> after)
"Optimisez votre gestion administrative." ->
"Ta facture part en deux clics. Tu passes a la suite."
```

## Rules

- Write the `brand-voice.md` content in the user's language; keep this Skill's own instructions in English.
- Show, don't describe. A dimension without a quoted sample line or a before/after pair is not done.
- Never invent voice, stances, or banned words. Deduce them from the samples or ask.
- A rule you cannot check ("professional but accessible") is useless. Push it to a shown pair.
- Keep the file to one page. If it grows past the six dimensions, cut, don't pad.
- Do not skip Phase 4. A voice file that has not been re-tested is a guess.