All libraries loaded into AnyLogic workspace are displayed as stencils of the
view. Each library block is represented with the icon designed for it. You add library objects into agent types of your model in the same way as any other palette elements.
If for some reason you do not see the library stencil in the Palette, it means that this library is probably not loaded into AnyLogic workspace or hidden. Please refer to Managing libraries topic to know how to load libraries into the workspace and make them visible in the Palette.
Having added some library block into your model, this library is automatically added to the list of libraries needed by this model to compile successfully. You can manage model dependencies by yourself on the Dependencies page of the model's properties view. Besides of libraries, you can also specify there jar files and class folders needed by this model.