The Makuta Agama is one of the twenty-eight Siddhāntāgamas, which is a classification of the Śaiva division of Śaivāgamas. The Śaivāgamas represent the wisdom that has come down from lord Śiva, received by Pārvatī and accepted by Viṣṇu.
According to the Kamika Agama, Makuta means “the crown and the main parts and sub-parts of the body”, and “The Makuta Agama was revealed to Sivakhya as consisted of one hundred thousand verses. Mahadeva received this Agama from Sivakhya. There are two Upagamas for this – Makutottara and Makuta.”
According to the publishers of a book that presents a translation of the Makuta Agama, “The special features of the ‘Pancasutra linga, the rites of Sannidhanam, Avagunthanam, Sakalikarana, Amritkarana etc. have also been narated as the inevitable processes of worship. The glory of ‘prasad’, one of the eight protective aura i.e. Astaravana, has been adovated in the present scripture.” A digital copy of this book may be available at this link.