The Compendium of Caraka 3.8.4

3.8.4

tato 'anantaramācāryaṃ parīkṣeta; tadyathā---paryavadātaśrutaṃ paridṛṣṭakarmāṇaṃ dakṣaṃ dakṣiṇaṃ śuciṃ jitahastamupakaraṇavantaṃ sarvondriyopapannaṃ prakṛtijñaṃ pratipattijñaman-*upaskṛtanidyamanahaṅkṛtamanasūyakamakopanaṃ kleśakṣamaṃ śiṣyavatsalamadhyāpakaṃ jñāpanasamarthaṃ ceti/

Immediately after that, he should examine the teacher, namely: one who has fully purified knowledge of the scriptures, who has observed clinical practice, who is skilled, dexterous, pure, of practiced hand, equipped with instruments, endowed with all intact sense faculties, knowing human nature, knowing appropriate action, whose knowledge is unadulterated, unarrogant, free from malice, not prone to anger, capable of enduring hardship, affectionate toward his students, an able teacher, and capable of imparting understanding.