At Longridge Editors, we are filing this in our lessons learned in the first year of business category.
“In the case of fiction, I think an author should provide an editor with the following information:
Depending on the story and the author’s plans I would also ask the author to provide additional information.
It is true that an editor can gather all of the above information herself from a first read of the manuscript. But leaving the task to the editor means that there is no assurance that something important will not be missed or misinterpreted. More importantly, it wastes valuable (and costly) time that could be better spent actually editing.”
Read more of this valuable post via The Business of Editing: What an Author Should Give an Editor « An American Editor. It includes suggestions for what editors should have in advance from authors of nonfiction work as well.