Thanks for your inquiry. Please note that GroupDocs.Annotation for .NET 3.x is a UI-Independent API that can be integrated in any .NET project. We have a GroupDocs.Annotation SharePoint plugin that demonstrates how API can be integrated with SharePoint server 2013. As our showcases/plugins are open-source, we’d recommend you to explore the plugin and enhance it to any extent or as per your use-case. We already shared a demo project with you that exposes how API works with SQL server in this post. Please explore both projects and enhance them or develop a new one following the resources we’ve shared.