Currently, there is very limited accounting visibility in WCS itself. In fact, if you want detailed accounting you need to look at ACS AAA logs.
CSCta98733 Need TACACS accounting support on WCS.
The above case number can be used for bug tracking. It hasn’t been mentioned WHEN this feature will go in and I understand it was “postponed.”
WCS currently does offer very limited local visibility into WHO and WHEN they logged in.
Go->Administration->AAA->(User/groups/active sessions) and click on Audit Trail.
Again, very limited and pretty disappointing.