Amazing book, read it with a decent Taḥqīq which was done by the late Sayyid Muḥammad Riḍa al-Ḥusaynī al-Jalālī (may Allah have mercy on his soul).
The author of this book of Rijāl is immaculately precise, and a deep read of this book provides a lot of insight into the early Imāmī community and their endeavours in the science of Ḥadīth verification.
May Allah be pleased with the author.