diff --git a/apiclient/discovery.py b/apiclient/discovery.py
index db4dd47..b202913 100644
--- a/apiclient/discovery.py
+++ b/apiclient/discovery.py
@@ -44,6 +44,8 @@
 DISCOVERY_URI = ('https://www.googleapis.com/discovery/v0.3/describe/'
   '{api}/{apiVersion}')
 DEFAULT_METHOD_DOC = 'A description of how to use this function'
+
+# Query parameters that work, but don't appear in discovery
 STACK_QUERY_PARAMETERS = ['trace']
 
 
@@ -219,21 +221,29 @@
     httpMethod = methodDesc['httpMethod']
     methodId = methodDesc['rpcMethod']
 
-    argmap = {}
+    if 'parameters' not in methodDesc:
+      methodDesc['parameters'] = {}
+    for name in STACK_QUERY_PARAMETERS:
+      methodDesc['parameters'][name] = {
+          'type': 'string',
+          'restParameterType': 'query'
+          }
+
     if httpMethod in ['PUT', 'POST']:
-      if 'parameters' not in methodDesc:
-        methodDesc['parameters'] = {}
       methodDesc['parameters']['body'] = {
           'description': 'The request body.',
           'type': 'object',
           }
 
+    argmap = {} # Map from method parameter name to query parameter name
     required_params = [] # Required parameters
     pattern_params = {}  # Parameters that must match a regex
     query_params = [] # Parameters that will be used in the query string
     path_params = {} # Parameters that will be used in the base URL
     param_type = {} # The type of the parameter
-    enum_params = {}
+    enum_params = {} # Allowable enumeration values for each parameter
+
+
     if 'parameters' in methodDesc:
       for arg, desc in methodDesc['parameters'].iteritems():
         param = key2param(arg)
@@ -260,7 +270,7 @@
 
     def method(self, **kwargs):
       for name in kwargs.iterkeys():
-        if name not in argmap and name not in STACK_QUERY_PARAMETERS:
+        if name not in argmap:
           raise TypeError('Got an unexpected keyword argument "%s"' % name)
 
       for name in required_params:
@@ -278,16 +288,17 @@
         if name in kwargs:
           if kwargs[name] not in enums:
             raise TypeError(
-                'Parameter "%s" value "%s" is not in the list of allowed values "%s"' %
+                'Parameter "%s" value "%s" is not an allowed value in "%s"' %
                 (name, kwargs[name], str(enums)))
 
       actual_query_params = {}
       actual_path_params = {}
       for key, value in kwargs.iteritems():
+        value_as_str = _to_string(value, param_type.get(key, 'string'))
         if key in query_params:
-          actual_query_params[argmap[key]] = _to_string(value, param_type[key])
+          actual_query_params[argmap[key]] = value_as_str
         if key in path_params:
-          actual_path_params[argmap[key]] = _to_string(value, param_type[key])
+          actual_path_params[argmap[key]] = value_as_str
       body_value = kwargs.get('body', None)
 
       if self._developerKey:
@@ -321,6 +332,8 @@
     if len(argmap) > 0:
       docs.append("Args:\n")
     for arg in argmap.iterkeys():
+      if arg in STACK_QUERY_PARAMETERS:
+        continue
       required = ""
       if arg in required_params:
         required = " (required)"
diff --git a/oauth2client/client.py b/oauth2client/client.py
index c8d0941..0433600 100644
--- a/oauth2client/client.py
+++ b/oauth2client/client.py
@@ -37,12 +37,12 @@
 
 
 class FlowExchangeError(Error):
-  """Error occurred during request."""
+  """Error trying to exchange an authorization grant for an access token."""
   pass
 
 
 class AccessTokenRefreshError(Error):
-  """Error occurred during request."""
+  """Error trying to refresh an expired access token."""
   pass
 
 
diff --git a/tests/test_discovery.py b/tests/test_discovery.py
index 6a48d0e..2e0104c 100644
--- a/tests/test_discovery.py
+++ b/tests/test_discovery.py
@@ -65,14 +65,14 @@
       buzz.activities().list(scope='@myself', userId='me')
       self.fail()
     except TypeError, e:
-      self.assertTrue('not in the list' in str(e))
+      self.assertTrue('not an allowed value' in str(e))
 
     # Parameter doesn't match regex
     try:
       buzz.activities().list(scope='not@', userId='foo')
       self.fail()
     except TypeError, e:
-      self.assertTrue('not in the list' in str(e))
+      self.assertTrue('not an allowed value' in str(e))
 
     # Unexpected parameter
     try:
@@ -108,6 +108,10 @@
     zoo = build('zoo', 'v1', self.http)
     request = zoo.query(trace='html')
 
+    parsed = urlparse.urlparse(request.uri)
+    q = parse_qs(parsed[4])
+    self.assertEqual(q['trace'], ['html'])
+
   def test_buzz_resources(self):
     self.http = HttpMock(datafile('buzz.json'), {'status': '200'})
     buzz = build('buzz', 'v1', self.http)