Personally I don't like this. Often enough there's includes in headers, which are an implementation detail for the functionality in the originally included header. Iwyu will just include that, increasing coupling between components.
fix_includes.py --ignore_re '^boost' < /tmp/outI can see value in removing unneeded includes, and doing that supervised every once in a while. The way it wants to add includes? Not so much.
(e.g. https://github.com/Itseez/opencv/blob/master/include/opencv2...)
A tool like this would see right through that and walk the tree all the way to the final leaf headers that actually implement the parts you use. This not only means one single include will balloon to many smaller ones, but when the library moves things around internally your code will break.
(Unclear if this is what this tool in particular will do, but I've certainly seen this behavior with Clion for example when it recommends what header to include.)