I’m a bit confused.
The documentation says that $input.item is not available in code node:
But when adding a Code node and switching the mode to “Run once per item”, the default code gives you an example which uses $input.item.
It makes seens for the “Run once for all items” mode, but not the other one.
Maybe the last column in the documentation table should be split in two columns for each code node mode.
Change my mind if I have a thinking error.