sandbox-exec is so frustrating. It could be a genuinely excellent solution to a whole bunch of sandboxing problems, except...
1. Documentation is virtually nonexistent. I think that is inexcusable for a security tool!
2. The man page says that it's deprecated, and has done for around a decade. No news on when they will actually remove it, maybe they never will? Hard to recommend it with that axe hanging over it though.