Purpose & Goals
Why are you having the workshop? Goals?
The purpose is the one sentence everything else in the workshop has to serve.
Purpose and goals are the spine of the whole design. Purpose is why the workshop exists at all: what change, decision, output or shared understanding you are trying to create. Goals are the specific things the group should leave with. Without a clear purpose, every other decision in the planning becomes harder, because you have no anchor to test choices against.
A well-written purpose statement is specific enough to use as a design tool. 'Align the team on the product roadmap for Q3' is a purpose you can build a programme around. 'Have a good team session' is not. The test is whether you could use the statement to decide what goes in and what stays out.
The purpose also belongs to the group, not just the organizer. Experienced facilitators check that participants understand why they are there and what they are expected to contribute. A group that does not know the purpose of their own session is hard to engage, because they cannot see what their effort is for.