You write on parchment, paper, or some other suitable writing material and imbue it with a magical script that lasts for the duration.

The script automatically rewrites itself to track the number and type of items in a container or shelf that fits within a 5-foot cube. Items removed from the container are crossed out but still visible on the list. When the spell ends, the script remains but no longer rewrites itself.

At Higher Levels. When you cast this spell using a 3rd-level spell slot, the duration is 30 days. When you use a 4th-level spell slot, the duration is a year and a day. When you cast this spell using a spell slot of 5th level or higher, it lasts until dispelled.