A library or a Script (as shown in the Script page in MainUI). If the latter, you can’t find the ID because it’s not a Rule so it doesn’t have an ID. If the latter, why not the former? See OH 3 Examples: Writing and using JavaScript Libraries in MainUI created Rules.
If you have a Script (i.e. it’s defined through the UI and appears in the list on the Script page, I don’t know how much I can help without more information.
I’ve circled the UID of the Create Rule Example in the screen shot above. That’s the ID you need to use.
