A chapter outline of a book is often called a chapter-by-chapter breakdown. This is a way of organizing the contents of the book before it is written. It helps an author to plan out the structure of the book, order the chapters and set up the flow of the narrative.
To create a chapter-by-chapter breakdown, the author will typically list out each chapter with a short description or topic. They may include key characters or plot points. The primary goal of the chapter-by-chapter breakdown is to give the author a big picture look at the entire book in order to test how the chapters fit together.
Most authors will use a chapter-by-chapter breakdown to map out the structure of the book and ensure that all the critical story elements are included. It can be a helpful tool for authors who are struggling to figure out the order of their chapters and the connections between them.
A chapter-by-chapter breakdown can also be useful for anyone else working on the book, such as an editor or publisher, as it provides an easy way to understand the structure of the book in a glance.