Useful query to get basic overview of extended events, actions and targets and their description.
SELECT p.name AS [Package-Name], o.object_type, o.name AS [Object-Name], o.description AS [Object-Descr], p.guid AS [Package-Guid] FROM sys.dm_xe_packages AS p JOIN sys.dm_xe_objects AS o ON p.guid = o.package_guid WHERE o.object_type = 'event'
SELECT p.name AS [Package-Name], o.object_type, o.name AS [Object-Name], o.description AS [Object-Descr], p.guid AS [Package-Guid] FROM sys.dm_xe_packages AS p JOIN sys.dm_xe_objects AS o ON p.guid= o.package_guid WHERE o.object_type ='action'
SELECT p.name AS [Package-Name], o.object_type, o.name AS [Object-Name], o.description AS [Object-Descr], p.guid AS [Package-Guid] FROM sys.dm_xe_packages AS p JOIN sys.dm_xe_objects AS o ON p.guid = o.package_guid WHERE o.object_type = 'target'