text-composition butler

A "gentleman's gentleman" who's mainly tasked with proofreading his fumble-fingered master's hastily-composed missives, essays, and other literary creations, pointing out and/or correcting all the errors, and then either passing the resulting "perfected" paperwork back to his boss, or sending said correspondence on its way to it intended recipients.

As clever and talented as Jeeves was, it's entirely probable that he could have also served the dim-witted Bertie Wooster in the role of text-composition butler; perhaps he might instead have suavely suggested that, "You might want to consider a modern word-processor, Sir... it will underline spelling and grammar errors for you, so that you can correct them immediately as you go along."