In 1500, Claudio and his father Trimalchio were sent with two other Thieves to spy on Niccolò Machiavelli. On the way, Claudio was attacked by Borgia crossbowmen, and could not escape the attack. La Volpe, the Guild leader, and Ezio Auditore da Firenze came to his aid, and Claudio was safely escorted to his father by Ezio.
Claudio, however, found that he was not cut out for thievery, and later, was lent some money by La Volpe to buy a ship. He later assisted Ezio Auditore in his pursuit of Cesare Borgia, who had recently escaped from his confinement in the Castel Sant'Angelo, by pursuing him down the Tiber.
- The name Claudio is generally thought to be derived the Latin claudo, "to hide, confine".
- In the non-canonical mobile adaptation of Assassin's Creed: Brotherhood, Claudio is abducted by the Followers of Romulus—known as the Wolfmen in this version—instead. Rather than the thieves faction, it is the Assassin apprentices whose trust is earned by Ezio's rescue of Claudio, though in this case it was not so much on Ezio's initiative so much as it was expressly requested of him to earn their allegiance. Ezio saves Claudio after assassinating the leader of the Wolfmen, Romulus, at the Colosseum with the aid of an apprentice.