Where the Kangyur gathers texts held to be the Buddha's own words, the Tengyur, translation of treatises, gathers everything built on top of them: commentaries on individual sutras and tantras, independent philosophical treatises, and technical works on logic and epistemology (pramana), grammar, poetics, medicine and other subjects the great Indian Buddhist monastic universities such as Nalanda and Vikramashila treated as part of a complete education. The Tengyur is considerably larger than the Kangyur, running to over two hundred volumes in the standard editions, and it preserves the work of major Indian Buddhist philosophers including Nagarjuna, Vasubandhu, Dignaga and Dharmakirti in Tibetan translation, alongside original commentarial writing by Tibetan scholars themselves.
The collection reflects the scholastic, argument-driven monastic culture Tibetan Buddhism inherited from late first-millennium Indian Buddhist universities, transplanted and continued in Tibet after Buddhist institutional life in India itself declined following the twelfth and thirteenth centuries. Later Tibetan scholars added their own original commentarial writing to the collection over the centuries following Buton's initial sorting, meaning the Tengyur, unlike the Kangyur, continued to grow with genuinely new material even after its basic organizing structure was fixed in the fourteenth century.