Board Thread:Versus Debates/@comment-44916514-20200123204114/@comment-9782468-20200218143955

@Ninja I think it was a combination. The crow was obviously reacting to Itachi's MS. So I think that it came out due to Itachi's MS and began its build-up to Koto, but when it was ready, Itachi's eyes had closed and therefore the crow couldn't identify its target, so it waited to cast it. Then Itachi opened his eye and the crow reacted accordingly.

So while Koto itself doesn't need eye contact, I think seeing the eye was a prerequisite for the crow itself using it