I'm not an Instacart recruiter but I'm in-house at a company that runs a very similar process. I've also talked to a few Instacart candidates who debriefed with me after. So this is secondhand but I think it's accurate enough to be useful.
The recruiter screen is typically 30 minutes. Don't mistake it for a warmup. Instacart recruiters are screening for fit signals before you ever talk to an engineer. Here's what they're actually evaluating:
What the recruiter is calibrating: Why Instacart specifically. 'I love grocery delivery' is not enough. They want to see you've thought about where the company is going, the business context, maybe something about their tech stack or growth priorities. A generic answer here is a yellow flag. What level you're actually coming in at. They'll ask about scope: how large was your team, what was your impact radius, who did you work with outside your immediate team. They use this to figure out if you're L4/L5/staff level before the loop even starts. Compensation expectations. Yes, this early. If your number is totally off they'd rather find out now. Why you're leaving your current role. They're listening for stability signals. If you mention interpersonal drama or seem like you're running away from something, it registers. Timeline. How urgent is your search. They use this to manage their own pipeline.
One thing that trips people up: being too vague about their experience because they haven't started prepping yet. The recruiter screen IS prep. Treat it like a light version of the behavioral round. Have 1-2 quick stories ready about scope and impact.
If the screen goes well you'll usually hear in 2-4 business days about next steps.