The rubric heavily draws from what questions the candidate asks, and which topics they choose to zoom in and spend time on. It's interesting; I warn candidates that studying for it ahead of time (for instance: for a long time our workdays were all based on a block storage problem) puts you at a disadvantage, by robbing you of good questions to ask. It's not a big disadvantage, but interview-style preparation isn't doing much to help you either.
I'm always reluctant to talk too much about the workday process, in particular because the more I describe it the less chill it sounds. In reality, it's you joining a Slack channel with an engineer from our team and just shooting the shit about something we're (in the simulation) planning to build.
A lot of what that challenge is evaluating is communication. We're an all-remote company with team members in virtually ever time zone; being able to work out in the open in the environment we've created is important.
I think our workdays are a pretty quirky feature of our process. You could instead do a scripted interview, where everybody gets precisely the same questions or prompts. The big thing we do with the workday that I think everyone should clone is: deliver the interview over Slack, and don't allow the person delivering the interview to grade it; instead, have someone else grade from the transcript. It was like a light went off (on?) for us when we figured out to stop having workday participants offer performance feedback about candidates.
(One thing you immediately get from it is a process to iterate on the quality of your staff delivering the workday/interview; you can immediately see which team members click with candidates and which don't, and then nudge people in the right direction. It is wild to me that people do free-form interviews without this kind of iteration system in place.)