This is a sample list of questions. This should be a rolling list of questions you hear from LPs.

Idea + Market Pull Why is now the right time to start this? Why couldn't this business have succeeded 24-48 months ago? What newly made it possible whereas formidable entrants couldn't exist before? If there's nothing new, incumbents would have line-extended into here already.
Idea + Market Pull Find out if they're thorough: Do they have a full understanding of the problem? - Can you describe the history of this idea and how it builds on prior attempts to solve this problem? - Ask them the why behind their decisions to help them go deeper.
Idea + Market Pull What is “hard” about what they’re trying to build?
Idea + Market Pull Do they have basic risk awareness? What are the biggest risks? Where does this fail? And what are you doing to mitigate each risk.
Economics Does the company understand its unit economics? How confident are they, and how correctly so, in their understanding of which parts of the business have operating leverage?
Economics Is it big enough? Is the addressable market big enough to support at least $200M/year in revenue?
Economics Pace of movement and capital efficiency (e.g. how far can they can on little capital).
Economics How capital intensive will this business be over time?
Economics Sanity check margin potential over time—will they get squeezed and are they raising enough money. In today's market, it's important they have a path to breakeven before running out of cash.
Team Are the founders driven to do this for a long time; is this the last business they’ll ever start. Is starting this company the natural culmination of what the founder has been working toward in the years leading up to incorporation?
Team Do the founders seem unstoppable? Find out if they're relentless: Probe what they're doing to keep learning their market and iterate faster.
Team I would tell my best friend to join this team.
Team Are they desperate for success or for their product to exist or are they larping as founders?
Team Can the founder(s) both build and sell?
Speed Are they moving fast? What do you want to get done by the end of the year?