Geospatial Administrator has a number of built-in XFM feature properties that can be incorporated into the feature property definition.  For example, you may want to place or capture the origin coordinates of a point feature.  In that case, you would use the FeaturesCentroid.X , Y or Z property that's built-in and available to use.

Point Feature Origin:

Calculates the X, Y or Z coordinates of the point feature.

Key = editing,  Synch Preference = OFF

The following will be triggered after the feature has been placed, and the Edit mode has activated.  An alternate approach is to create an annotation sub-feature which automatically triggers the Edit key for the calculating the feature property.  Or, use the Sync1 MDL application that enables editing keys to auto-update anytime the feature is modified with Map or MicroStation.  Refer to:  Auto update editing initial values (Sync1)

Value Type = cExpression

Value = [FeatureName.FeaturesCentroid.X]

Value = [FeatureName.FeaturesCentroid.Y]

Value = [FeatureName.FeaturesCentroid.Z] - For 3D only

Other built in XFM properties include:

Area, Length, Perimeter, Level, Color, Weight, Style, ElementID, ElementClass, Transparency, Priority, Locked, Modified, New, Solid, ViewDependent, GraphicGroup, Model, ModifiedTime, Fill and CellName.

For additional information on the built-in XFM properties, please refer to the product documentation found at docs.bentley.com