521a πότερος with art

ἐπὶ ποτέραν οὖν με παρακαλεῖς τὴν θεραπείαν τῆς πόλεως,
I thought that poteros would not take an article

It seems weird to me, but maybe it’s doing something like explanation, as ἀνήρ ὁ σοφός

i think this would be the only explanation possible