Explain the syntax of the following sentence: "erro uelut uentis discordibus acta phaselos"

The predicate/main verb of the sentence is 'erro' (erro, errare, erravi, erratus), which is the 1st person singular present active indicative of 'to err' or 'wander'. 'velut' is a conjunction which introduces a simile. 'phaselos' is in the feminine nominative singular and is the subject of the simile, here in its Greek nominative form rather than the Latin phaselus, phaseli (f). 'acta' is in agreement with the subject and is the feminine nominative singular perfect passive participle of ago, agere, egi, actus. 'uentis discordibus' is a noun and adjective pair in the masculine ablative plural (ventus, venti (m) and discordibus, discorduba, discordibum) and is the ablative of instrument after the passive participle 'acta'.