Abu Bakr al-Bayhaqi: Weak
Ahmad ibn Hanbal: He magnified him, and once said: Someone like this is not asked about, and once: There is no one in Kufa with more excellent narrations than him
Ahmad ibn Salih al-Jalil: Trustworthy
Ibn Hajar al-Asqalani: Trustworthy, Established
Al-Dhahabi: Trustworthy, Highly Mentioned
Sufyan ibn Uyainah: Al-Harith was among the elite companions of Ibn Mas'ud
Muhammad ibn Sa'd, the scribe of al-Waqidi: Trustworthy, Narrated many hadiths
Yahya ibn Ma'in: Trustworthy, and once said: There is no one in Kufa with more excellent narrations than him