In order to identify the reducing agent let us check the oxidation states
I2 + Ti+4 ----> Ti + IO3- reducing agent
I2 : oxidation state of I = 0
Ti^+4 = oxidation state of Ti = +4
Ti : oxidation state = 0
IO3^-1 , oxidation state of Iodine = +5
So here the Ti undergoes reduction hence it is oxidizing agent
Where iodine undergoes oxidation hence it is reducing agent