Section specific Word Count for Google Docs

I want a simple add-on for Google Docs that display the word count of all of the sections, as divided by the toc. So, if I am writing a novel with many chapters (all of them in the same document) I can know the word count of each chapter without the need to select any text. The add-on could find two headings and count the word between the two (ignoring the headings word count). The display could be a simple outline, with the heading name and the word count.