Usooli Scholar Sheikh Al Naini believed Al Kafi is authentic

 

Al Khoei writes:

“More than one from the scholars have mentioned that all the narrations in al-Kafi are sahih and there is no reason to reject anything from it due to its weak chain. And I heard our Teacher Sheikh Muhammad Hussein Al Naini in one of his meetings saying: ‘Indeed, debating the chains of the narrations in al-Kafi is what the incompetent [person] does.’”

 📚Mujam Rijal al-Hadith, V1, P81

*Note, Al Khoei narrated Al Nainis opinion, it wasnt his own view.