I may offer anecdata on Claude and P4. I asked it to prototype some code and move what it generated into separate header and source files. In the process of doing it Claude decided to move every edited file from the workspace into its own CL. Then it noticed that something was up and tried to put everything back. I found the part of the comment from Claude suggesting that I may go recheck that it managed to put everything back to be hilarious. Just my 2c, I guess Claude is really comfy with tools that are mostly used in training and not old monster systems like P4.