The four lines that change the output
Long briefs are not better briefs. In practice, output quality is dominated by four things, and everything else is context.
- Who, specifically. "Millennials" is not an audience. "People who have just inherited a house they cannot afford to keep" is.
- The tension. What does this person believe, want, or fear that makes the category difficult? No tension, no idea.
- What has to be true afterwards. A behaviour change, not an awareness metric.
- What you will not do. The boundary is the most generative line in any brief. It forces specificity faster than any amount of description.
What to leave out
Background that exists to justify the budget adds nothing. Neither does a competitor audit written to show diligence, or a tone-of-voice paragraph that could be pasted into any brief in the building.
If a line would be equally true for a rival brand, cut it. It is costing you specificity and buying you nothing.
Write for a collaborator, not a search box
The habit of prompt-writing pushes people towards keyword-stuffed instructions. Briefs work the other way. Write the way you would brief a sharp freelancer who has never heard of your client: plain sentences, real detail, honest about what is unresolved.
Saying "we genuinely do not know whether the problem is price or trust" is more useful than pretending to a certainty you do not have. It tells the engine where the real work is.
Then argue with what comes back
A brief is the start of a conversation. The first response is a draft position, not an answer. Push on it, say what is wrong, and let the next round be sharper.
That back-and-forth is where the idea gets built. A tool that only accepts a brief and returns a finished artefact has skipped the part that mattered.