Board Thread:Naruto News/@comment-26937472-20151130084303/@comment-945885-20151204010933

The novel version is almost certainly based on a longer script that was pared down for time constraints. That's what happens with virtually every novelization. So, it's not strictly canon, but you can consider that stuff to be "additional context," in the same way that films often have deleted scenes or unused storyboards.

Also, keep in mind that Japanese fandom is a lot less concerned with this sort of "is it canon or isn't it canon?" stuff, and thus Japanese publishers, authors, etc. rarely make any sort of explicit distinctions regarding what story elements are "official."

There currently is no list of what media is specifically considered canon. There is no source that I'm aware of which explicitly says "X is canon, Y non-canon." The closest we have to that are promotional materials and copy from advertisements and magazine articles which may or may omit media from timelines, or specifically use phrases like, "the next chapter in Kishimoto's saga!"