See this previous question and answer.
Zn^0(s) -2 e --> Zn^2+(aq) (oxidation)
2Ag^+(aq) +2 e --> 2Ag^0(s) (reduction) The valence is less, reduced.
Ag is the oxidizing agent and Zn is the recucing agent
Oxid izing agents are reduced and reducing agents are oxidized. .Source(s): Teahcher