Hi Darryl, adding bookmarks to a webmap would be really handy for us, since we have over 1000 points to survey. I'm not really sure how to run this though, I saved the github files in a folder, and inputted your code
populateBookmarks.py -u USERNAME -p PASSWORD -layerURL URL_TO_MAP_SERVICE -labelfield FIELD_NAME -itemid AGOL_ITEM_ID -portal PORTAL_URL
in the ArcMap python terminal. It just keeps showing syntax error though. Thanks very much for your help