You are right... you can add releases: https://musicbrainz.org/doc/How_to_Add_a_Release https://musicbrainz.org/doc/How_to_Add_a_Release But i did not find any

You are right... you can add releases: https://musicbrainz.org/doc/How_to_Add_a_Release https://musicbrainz.org/doc/How_to_Add_a_Release But i did not find any documentation, how to do this programmatically / via API, which would be essential for m4b-tool. It's not like I want to criticize your proposal. You are absolutely right, yet another track / chapter database would not be very helpful in general - but the things that i could find out about musicbrainz do not really fit my needs. Especially, because musicbrainz is more for music than for audiobooks. In my opinion, the usability of the web interface, the filtering options and the api of musicbrainz are not always helpful... An example: Open musicbrainz.org and try to find "Harry Potter" with the search bar on the upper right. It's nearly impossible without further investigation. Sure... you could provide the authors name "Joanne K. Rowling" and then do a facetted search for the title, but in my opinion this could be much better. m4b-tool is able to use the music-brainz-id for loading chapters and tagging audiobooks. But another problem is, that there is a shift between the cd version, mp3 version, download version etc. of the audiobook. So chapter marks have to be matched via silence detection and best fit, which is not always 100% accurate... I am working on an audiobook database, that contains very sophisticated filtering options. It's a project just for fun and perhaps it will never be released / online :-) I could certainly do better with my time and the value is questionable, but as long as it's fun... ;)