GRAPH-BASED LABELING OF HETEROGENOUS DIGITAL CONTENT ITEMS

Technologies for graph-based labeling of digital content items include, in some embodiments, for digital content items received from user systems by an application system, generating and storing a content graph. The content graph can include labeled nodes that correspond to digital content items that have labels, unlabeled nodes that correspond to digital content items that do not have labels, and edges that indicate relationships between content items. Edge data for an edge between an unlabeled node and an adjacent node can be retrieved from the content graph. Responsive to a set of inputs that includes the retrieved edge data and embedding data associated with the unlabeled node, a machine learning model trained on labeled nodes and edges of the content graph can assign a label to the unlabeled node.