Who is Brooksmith from Tales of Henry James: The Texts of the Stories, the Author on His Craft, Background and Criticism and what is their importance?

Brooksmith is the refined, well-educated but short butler of Mr. Offord. With consummate skill, he selects the participants in Mr. Offord's famous salon, ensuring that misunderstanding are avoided and conversation flows smoothly. When Mr. Offord dies, Brooksmith is crushed because he has lost his best friend and the intellectual stimulation of the salon.