I was looking for a solution to this and eventually just wrote a script to do it. Just make a temp directory, and run this in the python console, and have fun.
#############################################
# Description: Updates the description of each layer in
# the current mxd.
#
# Useful if the metadata changes, and you want the metadata
# to be reflected in the mxd layer description
#############################################
import arcpy
from xml.etree.ElementTree import ElementTree
#set local variables
dir = arcpy.GetInstallInfo("desktop")["InstallDir"]
translator = dir + "Metadata/Translator/ESRI_ISO2ISO19139.xml"
mxd = arcpy.mapping.MapDocument("CURRENT")
df = arcpy.mapping.ListDataFrames(mxd)[0]
temp_path = "C:/temp"
for layer in arcpy.mapping.ListLayers(mxd, "*", df):
if not layer.isGroupLayer:
description_text = ""
path = temp_path + '/' + layer.datasetName + '.xml'
print path
arcpy.ExportMetadata_conversion(layer.dataSource, translator, path)
dom = xml.dom.minidom.parse(path)
fields = ('abstract', 'purpose', 'credit')
for field in fields:
tags = dom.getElementsByTagName(field)
print str( len(tags) ) + ' | ' + str( tags )
if len(tags):
tag_string = tags[0].getElementsByTagName('gco:CharacterString')[0].childNodes[0].nodeValue
description_text = description_text + "\n\n" + field.capitalize() + ":\n" + tag_string
print description_text
layer.description = description_text
if field == 'credit':
layer.credit = tag_string
