Every project brief should answer 5 questions. If it helps, you can even create document headings or presentation slides with these questions to structure your brief: What, Who, Why, Why Now, and How.
What? What are we talking about? What’s the problem?
Who? Who does this impact? Who’s doing the work?
Why? Why is this important?
Why now? Why are we prioritising it now?
How? How do we plan to fix it? How might our plans change?