What a strong brief always contains
One behavioral objective. Not 'increase engagement' or 'grow brand awareness', but: what should the target audience concretely do as a result of this campaign? Make a purchase, complete a form, share something, come back. One thing. Name more than one and you are not helping the agency, you are dividing their focus.
The right audience, not the broad one. 'Women aged 25 to 45' is not an audience, it is a demographic slice. Describe the mindset, the situation, the moment. Who is the most valuable user you are trying to reach? What are they doing when they are not thinking about your brand?
What has already been tried. Agencies spend hours developing ideas that have already been rejected internally. Tell them what did not work in previous campaigns, and why. This is not admitting failure. It is providing useful information.
Constraints, not the solution. State the parameters: budget, timeline, technical limitations, required integrations. But do not write the solution into the brief. The moment a brief says 'we want to build a game' or 'make something for TikTok', it has shifted from a problem definition to a fill-in-the-blank exercise.
What success looks like. Not vague ambitions, but concrete measurement points. Which KPI decides whether the campaign succeeded? Participation rate, return visits, conversion, opt-ins? Agencies design differently when they know what they will be judged on.