Senior asks arrive vague on purpose. "Make us faster." "Get AI into the product." "Fix compliance." The executive is naming a direction and trusting someone to turn it into a thing that can actually be built. That translation is a big part of the job.
The first move is not to start working. It's to find out what success looks like to the person who asked. "Faster" for whom, measured how, by when, and what does it unlock. The same three words can mean five different programs, and building the wrong one fast is worse than building the right one a week later.
I write my interpretation down and play it back: here's what I think you mean, here's what I'd measure, here's what I'd explicitly not do. The not-doing part is where ambiguity hides. Naming what's out of scope forces the real boundaries into the open, and that's usually where the executive corrects you, which is exactly what you want before you've spent anything.
Then I size it honestly, including the parts they didn't ask about but will need. The goal of scoping isn't to make the ask sound easy. It's to make sure the thing you deliver is the thing they actually wanted.