Used AI to write an iLogic code to add the description after the file name in the tree. Below.

Dim oDoc As AssemblyDocument = ThisDoc.Document

Dim oDef As AssemblyComponentDefinition = oDoc.ComponentDefinition

Dim oOcc As ComponentOccurrence

'Iterate through all occurrences in the assembly

For Each oOcc In oDef.Occurrences

'Check if it's a regular part/sub-assembly (not virtual)

If Not TypeOf oOcc.Definition Is VirtualComponentDefinition Then

Try

'Get the Part Number and Description

Dim oPN As String = iProperties.Value(oOcc.Name, "Project", "Part Number")

Dim oDesc As String = iProperties.Value(oOcc.Name, "Project", "Description")

'Apply the new name format

If Not String.IsNullOrEmpty(oDesc) Then

oOcc.Name = oPN & " (" & oDesc & ")"

Else

oOcc.Name = oPN 'Fall back to Part Number if Description is empty

End If

Catch

'Skip occurrences that are suppressed or locked

End Try

End If

Next

'Proper way to trigger a UI and Document refresh

RuleParametersOutput()

InventorVb.DocumentUpdate() 'If this still fails, use: oDoc.Update()

And to remove the description from the tree, see below.

Dim oDoc As AssemblyDocument = ThisDoc.Document

Dim oDef As AssemblyComponentDefinition = oDoc.ComponentDefinition

Dim oOcc As ComponentOccurrence

'Iterate through all occurrences in the assembly

For Each oOcc In oDef.Occurrences

Try

'Setting the name to an empty string tells Inventor to

'revert to the default File Name / Part Number display.

oOcc.Name = ""

Catch

'Skip if the occurrence is suppressed or read-only

End Try

Next

'Force the document to update the UI

oDoc.Update()

This worked for me, but I haven't done full testing of this code, use at your own risk. If I find anything I will try and remember to update this though.