MLA Handbook Plus (5.132) includes more information about how to create your annotated bibliography in MLA style.
When annotating a citation, structure the citation in MLA style, including hanging indent for second and subsequent lines of citation. Indent the text of the annotation by a half-inch (so it should line up with the hanging indent).
The annotation should include the following aspects succinctly phrased (typically 1-2 sentences, no more than 1 paragraph in length):
From MLA Handbook Plus:
Moore, Nicole. The Censor’s Library: Uncovering the Lost History of Australia’s Banned Books. U of Queensland P, 2012.
The book provides a comprehensive history of Australian print censorship and discusses its implications for questions of transnationalism and the construction of the reader.