Individual subscribers can add custom entries and notes on AP Stylebook entries.
If you have an AP Stylebook Online site license, your account manager can add custom entries and notes that are available to all the users on your site license. This custom content will appear in searches and in the custom stylebook section of your site license. (https://www.apstylebook.com/custom_ap_entries)
Individual users on a site license can add custom entries and notes as well, but that content is only available to that user. It is not visible to other users on the site license.
Create a note on an AP Stylebook entry
Go to the entry and click the "add note" button below the AP Stylebook entry.
You can edit or delete a note after you save it.
Create a custom entry
Go to Custom Stylebook on your dashboard and click "add an entry." That will take you to this form to create an entry: https://www.apstylebook.com/custom_ap_entries/new
Each custom entry must have a title. A definition is optional. If you only wanted to show the styling of a person's name, a city, a company name or a product, you could enter that in the title without anything in the body. Everything you enter in the title and the body copy will be searchable.