Smile offers a special AppleScript terminal, Worksheet. By default Smile opens the Worksheet when it launches. When you quit Smile, Smile automatically saves it, as a text file in Users/[you]/Library/Application Support/Smile/.

You can switch off the automatic opening of the Worksheet in the Preferences dialog. If you closed the Worksheet and later you want to re-open it, use the open now button in the Preferences dialog.