The ArcGIS Item Information Tool is able to access your ArcGIS Online items. Launch the tool and you will be prompted for your ArcGIS Online credentials. Once logged in, you will see your folder listing of your ArcGIS Online content. Click on each folder to see the items contained within that folder along with how each item is tagged.
Using the Tag Editor:
The power of the Information Tool is in the Tag Editor tool which can be found along the top of the application. This tool provides a way to add new tags to selected items or to replace or remove tags.
It is a quick and efficient way to find repetitive tags within your online content, i.e Shoreline Change, Shoreline change, shoreline change. The tool also provides a summary of the number of items tagged with the same keywords.
To edit a tag, simply select it from the tag listing at the far right and choose to Replace Tag or Remove Tag.
To add a tag, select the item title from the list and click the Add New Tags button. Select multiple items by holding the shift or control keys. Be sure you are still in Tag Editor mode before clicking on an item otherwise you will be brought to the item content page in ArcGIS Online. Double click on an individual content item to add or delete tags for this specific listing.
Display items by tag to ensure all content is tagged properly.