In an annotated bibliography, each citation is provided in MLA style with a hanging indent as usual. On a new line after the citation, completely indent the annotation 0.5" to the left.
The annotation should be fully indented 1" from the original start of the entry to distinguish it from the citation. If it is one paragraph long, do not indent the first line. If there are two or more paragraphs, indent the first line of each. Don't add spaces between paragraphs.
Annotations generally include a summary and an analysis of the cited work. However, instructors may have specific guidelines which always override general standards. If you are unsure, check with the instructor!