Delegated Contributors are users you wish to delegate as contributors of bots who can only work on content they create or content that has been shared with them. Once added, these users can use a subset of the AtBot Admin Portal. See Permissions for more information.
To add a contributor, click the button and type in the UPN (login name) of the user. The field will perform a search and come back with the best match. Click Add User to add that user as a contributor