Here are the scry endpoints of Dill. They require the desk in the path prefix be empty, so the general format is .^([type] %d[care] /=//=/[some-path]).
%x - /sessions
Get all sessions.
A scy with a care of %x and a path of /sessions returns a (set @tas) of the current sessions. The %$ session is the default session.
Example
> .^((set @tas) %dy /=//=/sessions){%$}
%u - /sessions/[ses]
Does session exist?
A scry with a care of %x and a path of /sessions/[ses] where [ses] is a session name returns a ? of whether [ses] exists.
Example
> .^(? %du /=//=/sessions/$)%.y> .^(? %du /=//=/sessions/foo)%.n