Chandler is British and speaks with an Oxford accent. He is described as 'a lean and fit-looking young man with cheekbones sharp enough to slice bread and eyes of cobalt blue'. He wears a dark blue, well-tailored cashmere suit, cream colored shirt, and a metalic-copper tie—and a black bowler hat. He carries a silver-handled cane, in his right hand, instead of a staff or rod. And he has a very keen British sense of humor.
According to the author, Chandler specialises in divination and time magic, which makes him a good information gatherer. Part of why he has been made a Warden is so that the Council can keep an eye on him.
In the series
In Turn Coat, Chandler is guarding the entrance to the White Council headquarters from the Nevernever, a job typically staffed by five Wardens at once. There, Dresden nicknamed him John Steed[Footnote 1] after The Avengers[Footnote 2] character.
In Changes, in a letter to Dresden, Luccio tells that Chandler is the Warden she trusts the most, and thus assigns him to inform Dresden of the situation at Edinburgh which he does with his own letter. In order to authenticate his identity, he signed the letter Steed, as the two of them were alone when he nicknamed him thus.
In Peace Talks, Chandler is part of the Council's delegation to the gathering of accorded nations. Before the event, when he and the other Wardens confront Dresden about his connections with the White Court, he stays friendly and tries to strike a conciliatory tone.
In Battle Ground, he takes part in the defense of Chicago against the Fomor and the Last Titan. Chandler is part of a group including Harry Dresden, Yuki Yoshimo, Carlos Ramirez, Wild Bill, and River Shoulders that engages a group of Black Court Vampires led by Drakul to perform Necromancy in Graceland Cemetery.  After a short fight, Drakul drops Chandler through a gate to an unknown location. He is presumed dead, but his status is uncertain.