ArcGIS Pro 3.0 API Reference Guide
ArcGIS.Desktop.Editing Namespace / RelationshipDescription Class / Attributes Property

Attributes Property (RelationshipDescription)
Gets the attributes to assign the new row in the attributed relationship table.
Syntax
public IReadOnlyDictionary<string,object> Attributes {get;}
Requirements

Target Platforms: Windows 11, Windows 10, Windows 8.1

ArcGIS Pro version: 2.5 or higher.
See Also