[1] Regarded to be the largest and the most prominent work of Yamunacharya,[2] the Siddhitraya was an important foundational text for the philosophy of Vishishtadvaita.

In the invocatory verse, emphasis is placed on bhakti (devotion) to the Supreme Being (Vishnu), who is described to be the sovereign of the universe, time, and all souls, and is said to always be associated with Sri, his consort.

He offers refutations of the positions of philosophers such as Bhartrhari, Adi Shankara, and Bhaskara, citing fallacies and scriptural statements.

Yamunacharya contends the views of the Mimamsa school of philosophy and offers arguments against its position, which opposes the existence of a Supreme Being as well the omniscience and omnipotence of the concept.

[12][13] The saṁvitsiddhi is a treatise on ontology and offers the author's refutations against the Advaitic positions of the concepts of Brahman (Ultimate Reality), maya (illusion), and avidya (ignorance) in its interpretation of the Upanishads.