The input capacitor has two functions: 1. AC coupling. 2. Forming a high-pass filter with the input resistance of the preamplifier. The input capacitor can be selected from 0.1uF to 10uF. Lower capacitors provide better filtering at low frequencies, but larger capacitor can improve the CMRR of the system. For reference, an input capacitor of 0.1uF is used in the typical application circuit in the datasheet, and the 10uF input capacitor is used on the evaluation board.
As for the output capacitor, 1uF can be selected for most applications and serves as AC coupling.