Archivists have a long history of striving for objectivity in their descriptions of archival materials for their users. However, archivists are only capable of providing limited contextual knowledge about a collection due to their own subjective point of view and limitations on time and resources in processing. One proposed solution is the implementation of user-contributed annotations to online archival content, though many institutions have been slow to adopt this feature into their own digital initiatives. This study provides a content analysis of user annotations from three online archival collections: The Polar Bear Expedition Digital Collections, Beyond Brown Paper, and the Keweenaw Digital Archives. Findings showed that users most often engage in information-providing communication behaviors, with some variances between the three sites. In analyzing existing annotations, this study seeks to inform the role of user-contributed content in archival description.