Keaton was relieved to hear he didn't need his gun in Archer's office. He didn't have the incredible powers that Hades or Viktor had, so not having a gun with him would be a tactical disadvantage. Regardless, he was still human and needed his rest- being away from his gun for a little while would be beneficial.
He unsheathed his pistol, grabbed it by the barrel, and offered the handle to the security agent at the end of the hall.