I've written a script that would mass-add properties, however it appears that wbcreateclaim does not support marking the edit as a bot. The output I got back from the server was (for one request):

{u'claim': {u'type': u'statement', u'mainsnak': {u'datavalue': {u'type': u'wikibase-entityid', u'value': {u'entity-type': u'item', u'numeric-id': 43445}}, u'property': u'p21', u'snaktype': u'value'}, u'id': u'q4384168$3390B137-306C-4D79-B842-9E79361BB21F', u'rank': u'normal'}, u'pageinfo': {u'lastrevid': 6229461}, u'warnings': {u'main': {u'*': u"Unrecognized parameter: 'bot'"}}}

Version: unspecified
Severity: normal