Automator Folder Script to TAG files with a Dialog Box

Ok. Have a functionally correct Automator Folder Action that retrieves all available Tag names, and presents this as a selectable list once files are dropped on the assigned folder. It then sets each dropped file with these selected Tag(s). The dropped files are not moved out of this folder, per your requirements, but proper Folder Action implementation recommends they do not remain in the drop folder.

I have tested this on Yosemite and macOS Sierra without issue. Works as it should. With the exception of your specific folder name, you copy/paste the entire AppleScript below, into an Automator Run AppleScript action — after you have selected the default content, and removed it. How to configure in Automator was described in a similar post recently.

Save the Automator Folder Action (e.g. selTags), and selTags.workflow will be written into your ~/Library/Workflows/Applications/Folder Actions location. You can open this workflow using the Finder secondary menu's Open With : Automator, or by accessing Automator's Open Recent menu.

AppleScript:

In AppleScript, the possibility exists to get all of the active Finder tag names (those with their boxes checked in Finder Preferences : Labels, and present this as a scrollable list. You select the tag name from this list, and then that tag name (and its color) can be applied to the particular active file that was dropped on the folder.

I wrote a folder action on Jul 2 that applied a specific tag name (and color) to any file dropped on a specified folder. It shouldn't be too much work to adapt it to the first paragraph.

I don't have a complete integrated example. I have code that can retrieve all System and user-defined tag names into an AppleScript list. That tag list can be fed to a choose list prompt as input, so the tag names appear in a scrollable list for single, or multiple selection.

Questions for you before I can make modifications and post a custom solution:

1. Will you ever drop more than one file?
2. Will you need the ability to set more than one tag name on a dropped file? The choose list feature can be set for single, or multiple selection.
3. Are the freshly tagged files to be then moved/copied to a folder outside of the dropped folder?

When dropping more than one file, is it your expectation that you will be prompted once, for the list of tag(s) to set on all dropped files? Once I have that information, I can finish the code, test, and post.

Once you have dropped the file(s), and set the initial tag(s), you cannot run the script again to change them.

You can however, interactively add, change, or remove the tag(s) on single/multiple file(s) in the drop folder. Right-click/control-click/two-finger tap on the tagged file, and from the secondary menu, choose Tags... . Depending where your insertion point is located, you can add, change, or remove tags on one, or multiple files. Always press return in the Tags... field to set the changes.

Working on the drop folder script now...

Good.

I found a custom Swift function on stackoverflow that retrieves all System plus User Tag names. However, it does require at minimum that one has the non-default Swift interpreter/compiler installed, and mixing AppleScript and Swift together remains taboo.

I did not want to hold up your script solution while I attempted to translate that Swift code into AppleScript/Objective-C, or PyObjC, so the do shell script approach was effective use of time.

Sorry, there is still no action to Tag a file. You can use the old Label, but that is limited to the seven Label colors. It will Tag the files, but with "Green", "Yellow", etc.