When do you actually need to open Xcode if you have XcodeBuildMCP [0]?

I haven't opened Xcode in months. My terminal: Claude writes code. build_sim. launch_app_sim. screenshot describe_ui.

What still requires Xcode: Instruments profiling, Signing/provisioning

For UI iteration, describe_ui returning the accessibility tree might actually be more useful to an agent than a preview screenshot.

Multiple config files of Xcode projects are not publicly documented as far as I remember and personally I have preferred to require my agents not to modify them out of fear it might break something and be hard to fix. I don't know how agentic programming will work in Xcode but I would expect it to do it using a safer approach, so that's also another case where it might have an advantage.

Your workflow looks very interesting especially the describe_ui part, are you already able to do this today?

Can XcodeBuildMCP spit out definitions of C++ symbols? Did Apple just accidentally release a LSP server for Xcode projects? That would be sick.

I still open Xcode for every branch after having Claude do an initial implementation, to review the changes using its version editor, step through code using the IDE’s various code navigation features, and build/run to manually validate the changes. I do have claude analyze and test, though.

I still haven't found a useful way to replicate preview when iterating quickly on a view (though it's an edge case)