diff --git a/ironic/drivers/modules/agent_client.py b/ironic/drivers/modules/agent_client.py
index 6f715dca10..4130a27ab4 100644
--- a/ironic/drivers/modules/agent_client.py
+++ b/ironic/drivers/modules/agent_client.py
@@ -37,6 +37,7 @@ class AgentClient(object):
     """Client for interacting with nodes via a REST API."""
     def __init__(self):
         self.session = requests.Session()
+        self.session.headers.update({'Content-Type': 'application/json'})
 
     def _get_command_url(self, node):
         agent_url = node.driver_internal_info.get('agent_url')
@@ -64,13 +65,9 @@ class AgentClient(object):
         request_params = {
             'wait': str(wait).lower()
         }
-        headers = {
-            'Content-Type': 'application/json'
-        }
         response = self.session.post(url,
                                      params=request_params,
-                                     data=body,
-                                     headers=headers)
+                                     data=body)
 
         # TODO(russellhaering): real error handling
         try:
@@ -86,8 +83,7 @@ class AgentClient(object):
 
     def get_commands_status(self, node):
         url = self._get_command_url(node)
-        headers = {'Content-Type': 'application/json'}
-        res = self.session.get(url, headers=headers)
+        res = self.session.get(url)
         return res.json()['commands']
 
     def prepare_image(self, node, image_info, wait=False):
diff --git a/ironic/tests/drivers/test_agent_client.py b/ironic/tests/drivers/test_agent_client.py
index bfe91f83ab..406d3f8bf9 100644
--- a/ironic/tests/drivers/test_agent_client.py
+++ b/ironic/tests/drivers/test_agent_client.py
@@ -58,6 +58,11 @@ class TestAgentClient(base.TestCase):
         self.client.session = mock.Mock(autospec=requests.Session)
         self.node = MockNode()
 
+    def test_content_type_header(self):
+        client = agent_client.AgentClient()
+        self.assertEqual('application/json',
+                         client.session.headers['Content-Type'])
+
     def test__get_command_url(self):
         command_url = self.client._get_command_url(self.node)
         expected = self.node.driver_internal_info['agent_url'] + '/v1/commands'
@@ -84,14 +89,12 @@ class TestAgentClient(base.TestCase):
 
         url = self.client._get_command_url(self.node)
         body = self.client._get_command_body(method, params)
-        headers = {'Content-Type': 'application/json'}
 
         response = self.client._command(self.node, method, params)
         self.assertEqual(response, response_data)
         self.client.session.post.assert_called_once_with(
             url,
             data=body,
-            headers=headers,
             params={'wait': 'false'})
 
     def test__command_fail_json(self):
@@ -103,7 +106,6 @@ class TestAgentClient(base.TestCase):
 
         url = self.client._get_command_url(self.node)
         body = self.client._get_command_body(method, params)
-        headers = {'Content-Type': 'application/json'}
 
         self.assertRaises(exception.IronicException,
                           self.client._command,
@@ -111,7 +113,6 @@ class TestAgentClient(base.TestCase):
         self.client.session.post.assert_called_once_with(
             url,
             data=body,
-            headers=headers,
             params={'wait': 'false'})
 
     def test_get_commands_status(self):