Mañjuśrī­mūla­kalpa

"The Mañjuśrī­mūla­kalpa is the largest and most important single text devoted to Mañjuśrī, the bodhisattva of wisdom. A revealed scripture, it is, by its own classification, both a Mahāyāna sūtra and a Mantrayāna kalpa (manual of rites). Because of its ritual content, it was later classified as a Kriyā tantra and assigned, based on the hierarchy of its deities, to the Tathāgata subdivision of this class. The Sanskrit text as we know it today was probably compiled throughout the eighth century ᴄᴇ and several centuries thereafter. What makes this text special is that, unlike most other Kriyā tantras, it not only describes the ritual procedures, but also explains them in terms of general Buddhist philosophy, Mahāyāna ethics, and the esoteric principles of the early Mantrayāna (later called Vajrayāna), with an emphasis on their soteriological aims." (Source: 84000 https://84000.co/translation/toh543 )