In theory, I'm a fan of it. I think getting a working mock-up as a demonstration of an idea is far better than building something from a few napkin sketches and then iterating while we close in on the original vision.

As for my own work, I just spent a couple hours this afternoon in a back and forth discussion with claude code, asking it to mock up a UI for me before "we" start building it tomorrow. It was just a mock-up, so I didn't require precision, but I was impressed with some tidbits that came along for the ride.

Some things it did without me asking

* Mock data for the lists and pages in json format, so I could easily add records to it for different scenarios

* Working navigation between pages, including modals

* Working progress bars and timers

* Working list sorts and filters

* Toasts for functionality that was beyond the scope of the mock-up ("sending email to author of post" or "banning user")

* Not-half-bad animations and transitions between pages, screens, modals, etc

* A responsive layout that worked better than expected on mobile and desktop

* Some ideas I hadn't considered, that we then expanded upon

I would have mocked this up for a client, but not for myself. It's quite nice to have a working html / javascript / css mockup to play with while I flesh out my own ideas - with a benefit that I actually fully understand the output and can tweak it myself as needed.