Request or topic?
Before you size it, schedule it or say yes, look for three things.
The need
What should change, or what problem exists.
If it is missing, ask:"What should be different afterwards?"
The impact
Who is affected, and what happens if nothing changes.
If it is missing, ask:"Who does this affect, and what happens if we leave it?"
Why now
The deadline, event or pressure behind it.
If it is missing, ask:"What makes this matter now?"
Decidable = the need, plus the impact or why now.
A deadline and a senior name are not a need. If nobody can say what should be different afterwards, it is a topic, however urgent it sounds. Send one question back, not a meeting.
Dashboard. Customers keep asking. Before the conference would be great.
Send it back. There is pressure and there is a date, so it feels urgent and real — but nobody knows what the dashboard should show. A date on an unknown is how the worst commitments get made.
The quarterly revenue report takes 40 minutes to run and it blocks the close. Can it run in under five?
Decidable as it stands. No deadline, and it does not need one: the need and who it hurts are both stated. Short is not the same as vague.