A good brief is specific. The clearer you are, the better the result.
Describe what it does One sentence on the product. Then one sentence on the user — who they are, what they're trying to do. Then one sentence on why it exists.
List the features Bullet them. "Users can sign up, browse a feed, save items, message each other." We need to know the surface area.
Show us, don't tell us References are gold. Three to five sites or apps whose vibe you want, with one sentence each on why. "Linear — clean technical feel. Vercel — confident, modern. Resend — direct, no marketing fluff." That's worth more than ten adjectives.
Skip the strategy We don't need your mission statement, target market analysis, or competitive matrix. We need what you want built and what it should feel like.
Be honest about constraints If you have a logo already, send it. If you have brand colors locked, send them. If your domain is registered, share it. Anything we can skip designing means more time on the things that matter.