at discretion
Webster's Dictionary (GCIDE)
Discretion \Dis*cre"tion\, n. [F. discr['e]tion, L. discretio separation, difference, discernment, fr. discernere, discretum. See Discreet, Discern.]
1.Disjunction; separation. [Obs.] --Mede. [1913 Webster]
2.The quality of being discreet; wise conduct and management; cautious discernment, especially as to matters of propriety and self-control; prudence; circumspection; wariness. [1913 Webster]
The better part of valor is discretion.— Shak.[1913 Webster]
The greatest parts without discretion may be fatal to their owner.— Hume.[1913 Webster]
3.Discrimination. [1913 Webster]
Well spoken, with good accent and good discretion.— Shak.[1913 Webster]
4.Freedom to act according to one's own judgment; unrestrained exercise of choice or will. [1913 Webster]
At discretion, without conditions or stipulations. [1913 Webster] Discretional