You do not need a brief with diagrams. You do need a few honest answers. They keep the project small and they tell you quickly if you are not ready.
1. What is the task, in one sentence?
“Answer the after-hours call and write down what they need.” “Turn a walkthrough into a quote brief.” “Collect a special order without retyping it.” If the sentence needs a comma and three departments, split it.
2. What does a miss cost?
Lost work, a second visit, an hour of cleanup, a customer who does not call back. You do not need a spreadsheet. You need a cost you believe. If the miss is only irritating, fix the irritation with a simpler change.
3. Where does a person take over?
Write that line down. Price. Schedule. Exception. Advice. Complaint. The application should be proud of that line. If you cannot find it, the project is asking software to do a job you have not defined.
4. What is version one?
One service, one channel, one kind of request. Name what is out of scope on purpose. A first version that tries to cover the whole company will be late and vague, and your team will not trust it.
5. Who can say the design is wrong?
Someone who does the work, not only someone who owns it. Owners miss the step that happens in the truck or behind the counter. Give that person permission to reject a question that looks tidy and is useless.
6. What will you refuse to automate?
Naming the refusal is a design tool. It keeps the project from drifting into a demo of technology. It also makes the sales conversation shorter: you already know the boundary.
Bring those answers to a discovery conversation, or send them in a request. A sentence each is enough. If you want a guided pass first, the self-check on this site walks the same ground and does not keep your answers.
Related: what we can build, a short self-check, and how a project runs.