I made a python sample that can recreate this problem. import requestsimport jsondef test_api(): url_token = "http://localhost:8888/api/v2/token" url_add_folder = "http://localhost:8888/api/v2/folders" url_debug_log = "http://localhost:8888/api/v2/debug/log" s = requests.session() # get token. r = s.get(url_token) print "1:Fetched cookies was %s" % s.cookies json_response = json.loads(r.content) token = json_response["data"]["token"] print "2:Token was %s" % token # add folder by post. data = {"path": "/Users/zhaojin/Documents/abc", "token": token} r = s.post(url_add_folder, data) print "3:Result was %s" % r.content print "4.Request header was: %s \n Request body was %s" % (r.request.headers, r.request.body) # print s.get(url_debug_log).contentif __name__ == '__main__': test_api()the result is: 1:Fetched cookies was <<class 'requests.cookies.RequestsCookieJar'>[<Cookie GUID=39M3ObaYHoggLHrAcdVi for localhost.local/>]>2:Token was Aj6LD8j5qXv8cyoDiqF7SjR4gWPv_3xaCa8ySDby2C8pQ6nokWkOXJZHNFYAAAAA3:Result was invalid request4.Request header was: CaseInsensitiveDict({'Content-Length': u'112', 'Accept-Encoding': 'gzip, deflate, compress', 'Accept': '*/*', 'User-Agent': 'python-requests/1.2.3 CPython/2.7.3 Darwin/14.4.0', 'Cookie': 'GUID=39M3ObaYHoggLHrAcdVi', 'Content-Type': 'application/x-www-form-urlencoded'}) Request body was path=%2FUsers%2Fzhaojin%2FDocuments%2Fabc&token=Aj6LD8j5qXv8cyoDiqF7SjR4gWPv_3xaCa8ySDby2C8pQ6nokWkOXJZHNFYAAAAAAs the result shows, it seems that I correctly retrieved the cookie from the token api, and passed it to the add folder api. But it's still rejected. The log shows: [13:51:03] REST API: Can't fulfill request without valid tokenAny ideas where I did wrong? Thank you! Jin