Define a item with the key vfs.file.contents[/etc/zabbix/scripts/lectura] and data type Float

Define a preprocess step check for non supported with a default value of -123

Create the file empty -> the item will be unssuported with no value, error messate "String "" is not siutable for ..."

Delete the fiel -> the imte wil be supported with -123 value

I think that in both cases the item should not be unsupported and with the value -123