The foaf:yahooChatID property relates a foaf:Agent to a textual identifier assigned to them in the Yahoo online Chat system. See Yahoo's the Yahoo! Chat site for more details of their service. Yahoo chat IDs are also used across several other Yahoo services, including email and Yahoo! Groups.

See foaf:OnlineChatAccount (and foaf:OnlineAccount) for a more general (and verbose) mechanism for describing IM and chat accounts.