Data Jar is a Shortcuts-adjacent app that lets you store data for use in a shortcut as persistent key-value pairs. You can store text, numbers, booleans, lists, dictionaries, and files. This lets you read and update data directly from Shortcuts. As an example of how I use Data Jar, I have a shortcut that lets me rename a bunch of files at once. Some files are renamed sequentially and Data Jar helps me store the latest number for the files, and it gets updated with every new file I rename with it. It’s a great app, free for Mac and I personally recommend giving a big tip to the developer if you find Data Jar useful.