"Wise as serpents" in Matthew 10:16 doesn't use the normal Greek word for wise, but phronimos, which probably implies an awareness of the hazards and schemes of others rather than scheming of one's own.

Wary as serpents and uncomplicated as doves. In other words, be wary of the cunning of unbelievers but don't emulate them. Deal honestly with all, don't take the offensive, and don't engage in dishonest political maneuvering. Verses 17-20 explain what Yeshua meant.