AIClient::OnDeath() would take the same arguments as GameConnection::onDeath().
function GameConnection::onDeath(%this, %sourceObject, %sourceClient, %damageType, %damLoc)
%this - client
%sourceObject - the player which killed you (may be dead or nonexistant!)
%sourceClient - the client which killed you
%damageType - $DamageType::["Gun"] etc
%damLoc - "Head" all the time I think.