diff --git a/arkindex/documents/serializers/elements.py b/arkindex/documents/serializers/elements.py
index 7e08129b4bad21e35cad8293a2381c2f30e17143..bd9ef10be06b64157c47e1fa6b3c5856c486123f 100644
--- a/arkindex/documents/serializers/elements.py
+++ b/arkindex/documents/serializers/elements.py
@@ -944,7 +944,7 @@ class ElementBulkSerializer(serializers.Serializer):
 
 
 class ElementChildrenCreateSerializer(serializers.Serializer):
-    children = serializers.ListField(child=serializers.UUIDField())
+    children = serializers.ListField(child=serializers.UUIDField(), allow_empty=False)
 
     def validate_children(self, children):
         # Ignore duplicates, but preserve order.
diff --git a/arkindex/documents/tests/test_bulk_children.py b/arkindex/documents/tests/test_bulk_children.py
index 803d90202a44031ca49713abef45865721bbdc5f..ea4cc6ab8153780af25d45efb292eee869286015 100644
--- a/arkindex/documents/tests/test_bulk_children.py
+++ b/arkindex/documents/tests/test_bulk_children.py
@@ -69,7 +69,7 @@ class TestElementChildrenCreate(FixtureAPITestCase):
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertEqual(response.json(), {
-            "children": ["This field is required."],
+            "children": ["This list may not be empty."],
         })
 
     def test_parent_not_found(self):
diff --git a/arkindex/documents/tests/test_bulk_classification.py b/arkindex/documents/tests/test_bulk_classification.py
index 4b2b13fc3b75ceb98cfa9fe5b5941cf7f3833fbd..bad2fc1dec1dd2d2d1e4ed7829acd32bd2da8e0f 100644
--- a/arkindex/documents/tests/test_bulk_classification.py
+++ b/arkindex/documents/tests/test_bulk_classification.py
@@ -23,7 +23,7 @@ class TestBulkClassification(FixtureAPITestCase):
         cls.cat_class = cls.corpus.ml_classes.create(name="cat")
 
     def test_requires_login(self):
-        response = self.client.post(reverse("api:classification-bulk"), format="json")
+        response = self.client.post(reverse("api:classification-bulk"))
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
     @patch("arkindex.users.managers.BaseACLManager.filter_rights")
@@ -39,7 +39,6 @@ class TestBulkClassification(FixtureAPITestCase):
         with self.assertNumQueries(3):
             response = self.client.post(
                 reverse("api:classification-bulk"),
-                format="json",
                 data={
                     "parent": str(private_page.id),
                     "worker_run_id": str(self.local_worker_run.id),
@@ -68,7 +67,6 @@ class TestBulkClassification(FixtureAPITestCase):
         with self.assertNumQueries(3):
             response = self.client.post(
                 reverse("api:classification-bulk"),
-                format="json",
                 data={
                     "parent": str(self.page.id),
                     "classifications": [
@@ -94,7 +92,6 @@ class TestBulkClassification(FixtureAPITestCase):
         with self.assertNumQueries(4):
             response = self.client.post(
                 reverse("api:classification-bulk"),
-                format="json",
                 data={
                     "parent": str(self.page.id),
                     "classifications": [
@@ -124,7 +121,6 @@ class TestBulkClassification(FixtureAPITestCase):
         with self.assertNumQueries(5):
             response = self.client.post(
                 reverse("api:classification-bulk"),
-                format="json",
                 data={
                     "parent": str(self.page.id),
                     "worker_run_id": str(self.local_worker_run.id),
@@ -150,7 +146,6 @@ class TestBulkClassification(FixtureAPITestCase):
         with self.assertNumQueries(7):
             response = self.client.post(
                 reverse("api:classification-bulk"),
-                format="json",
                 data={
                     "parent": str(self.page.id),
                     "classifications": [
@@ -175,7 +170,6 @@ class TestBulkClassification(FixtureAPITestCase):
         with self.assertNumQueries(7):
             response = self.client.post(
                 reverse("api:classification-bulk"),
-                format="json",
                 data={
                     "parent": str(self.page.id),
                     "classifications": [
@@ -210,7 +204,6 @@ class TestBulkClassification(FixtureAPITestCase):
         with self.assertNumQueries(5):
             response = self.client.post(
                 reverse("api:classification-bulk"),
-                format="json",
                 data={
                     "parent": str(self.page.id),
                     "worker_run_id": str(self.local_worker_run.id),
@@ -239,7 +232,6 @@ class TestBulkClassification(FixtureAPITestCase):
         with self.assertNumQueries(4):
             response = self.client.post(
                 reverse("api:classification-bulk"),
-                format="json",
                 data={
                     "parent": str(self.page.id),
                     "worker_run_id": str(self.worker_run.id),
@@ -268,7 +260,6 @@ class TestBulkClassification(FixtureAPITestCase):
         with self.assertNumQueries(4):
             response = self.client.post(
                 reverse("api:classification-bulk"),
-                format="json",
                 data={
                     "parent": str(self.page.id),
                     "worker_run_id": str(worker_run.id),
@@ -302,7 +293,6 @@ class TestBulkClassification(FixtureAPITestCase):
         with self.assertNumQueries(3):
             response = self.client.post(
                 reverse("api:classification-bulk"),
-                format="json",
                 data={
                     "parent": str(self.page.id),
                     "worker_run_id": str(other_worker_run.id),
@@ -330,7 +320,6 @@ class TestBulkClassification(FixtureAPITestCase):
         with self.assertNumQueries(7):
             response = self.client.post(
                 reverse("api:classification-bulk"),
-                format="json",
                 data={
                     "parent": str(self.page.id),
                     "classifications": [
@@ -400,7 +389,6 @@ class TestBulkClassification(FixtureAPITestCase):
         with self.assertNumQueries(6):
             response = self.client.post(
                 reverse("api:classification-bulk"),
-                format="json",
                 data={
                     "parent": str(self.page.id),
                     "classifications": [
@@ -449,7 +437,6 @@ class TestBulkClassification(FixtureAPITestCase):
         with self.assertNumQueries(6):
             response = self.client.post(
                 reverse("api:classification-bulk"),
-                format="json",
                 data={
                     "parent": str(self.page.id),
                     "classifications": [
diff --git a/arkindex/documents/tests/test_bulk_element_transcriptions.py b/arkindex/documents/tests/test_bulk_element_transcriptions.py
index e47e5b5be9b169e3308a5b8f388f80ce0707e3c3..cfde7cbb708b25086cdc76d20669be937b307929 100644
--- a/arkindex/documents/tests/test_bulk_element_transcriptions.py
+++ b/arkindex/documents/tests/test_bulk_element_transcriptions.py
@@ -53,7 +53,6 @@ class TestBulkElementTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(4):
             response = self.client.post(
                 reverse("api:element-transcriptions-bulk", kwargs={"pk": self.page.id}),
-                format="json",
                 data=data
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -89,7 +88,6 @@ class TestBulkElementTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(13):
             response = self.client.post(
                 reverse("api:element-transcriptions-bulk", kwargs={"pk": self.page.id}),
-                format="json",
                 data=data
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -149,7 +147,6 @@ class TestBulkElementTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(13):
             response = self.client.post(
                 reverse("api:element-transcriptions-bulk", kwargs={"pk": self.page.id}),
-                format="json",
                 data=data
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -210,7 +207,6 @@ class TestBulkElementTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(13):
             response = self.client.post(
                 reverse("api:element-transcriptions-bulk", kwargs={"pk": self.page.id}),
-                format="json",
                 data=data
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -252,7 +248,6 @@ class TestBulkElementTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(13):
             response = self.client.post(
                 reverse("api:element-transcriptions-bulk", kwargs={"pk": self.page.id}),
-                format="json",
                 data=data
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -301,7 +296,6 @@ class TestBulkElementTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(11):
             response = self.client.post(
                 reverse("api:element-transcriptions-bulk", kwargs={"pk": self.huge_page.id}),
-                format="json",
                 data=data
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -324,7 +318,6 @@ class TestBulkElementTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(2):
             response = self.client.post(
                 reverse("api:element-transcriptions-bulk", kwargs={"pk": self.page.id}),
-                format="json",
                 data={}
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
@@ -339,7 +332,6 @@ class TestBulkElementTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(2):
             response = self.client.post(
                 reverse("api:element-transcriptions-bulk", kwargs={"pk": self.private_page.id}),
-                format="json",
                 data={}
             )
             self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
@@ -352,7 +344,6 @@ class TestBulkElementTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(4):
             response = self.client.post(
                 reverse("api:element-transcriptions-bulk", kwargs={"pk": self.page.id}),
-                format="json",
                 data={
                     "element_type": "text_line",
                     "transcriptions": [{
@@ -376,7 +367,6 @@ class TestBulkElementTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(5):
             response = self.client.post(
                 reverse("api:element-transcriptions-bulk", kwargs={"pk": self.page.id}),
-                format="json",
                 data={
                     "element_type": "paragraph",
                     "worker_run_id": bad_id,
@@ -445,7 +435,6 @@ class TestBulkElementTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(13):
             response = self.client.post(
                 reverse("api:element-transcriptions-bulk", kwargs={"pk": self.page.id}),
-                format="json",
                 data=data
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -477,7 +466,6 @@ class TestBulkElementTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(3):
             response = self.client.post(
                 reverse("api:element-transcriptions-bulk", kwargs={"pk": self.vol.id}),
-                format="json",
                 data={}
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -512,7 +500,6 @@ class TestBulkElementTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(13):
             response = self.client.post(
                 reverse("api:element-transcriptions-bulk", kwargs={"pk": top_level.id}),
-                format="json",
                 data=data
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -560,7 +547,6 @@ class TestBulkElementTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(13):
             response = self.client.post(
                 reverse("api:element-transcriptions-bulk", kwargs={"pk": self.page.id}),
-                format="json",
                 data=data
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -592,7 +578,6 @@ class TestBulkElementTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(5):
             response = self.client.post(
                 reverse("api:element-transcriptions-bulk", kwargs={"pk": self.page.id}),
-                format="json",
                 data=data
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -623,7 +608,6 @@ class TestBulkElementTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(13):
             response = self.client.post(
                 reverse("api:element-transcriptions-bulk", kwargs={"pk": self.rotated_page.id}),
-                format="json",
                 data=data
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -660,7 +644,6 @@ class TestBulkElementTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(13):
             response = self.client.post(
                 reverse("api:element-transcriptions-bulk", kwargs={"pk": self.mirrored_page.id}),
-                format="json",
                 data=data
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -697,7 +680,6 @@ class TestBulkElementTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(5):
             response = self.client.post(
                 reverse("api:element-transcriptions-bulk", kwargs={"pk": self.page.id}),
-                format="json",
                 data=data
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -713,7 +695,6 @@ class TestBulkElementTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(5):
             response = self.client.post(
                 reverse("api:element-transcriptions-bulk", kwargs={"pk": self.page.id}),
-                format="json",
                 data={
                     "parent": str(self.page.id),
                     "element_type": "text_line",
@@ -741,7 +722,6 @@ class TestBulkElementTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(5):
             response = self.client.post(
                 reverse("api:element-transcriptions-bulk", kwargs={"pk": self.page.id}),
-                format="json",
                 data={
                     "parent": str(self.page.id),
                     "element_type": "text_line",
@@ -775,7 +755,6 @@ class TestBulkElementTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(4):
             response = self.client.post(
                 reverse("api:element-transcriptions-bulk", kwargs={"pk": self.page.id}),
-                format="json",
                 data={
                     "parent": str(self.page.id),
                     "element_type": "text_line",
@@ -808,7 +787,6 @@ class TestBulkElementTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(12):
             response = self.client.post(
                 reverse("api:element-transcriptions-bulk", kwargs={"pk": self.page.id}),
-                format="json",
                 data={
                     "parent": str(self.page.id),
                     "element_type": "text_line",
@@ -848,7 +826,6 @@ class TestBulkElementTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(12):
             response = self.client.post(
                 reverse("api:element-transcriptions-bulk", kwargs={"pk": self.page.id}),
-                format="json",
                 data={
                     "parent": str(self.page.id),
                     "element_type": "text_line",
diff --git a/arkindex/documents/tests/test_bulk_elements.py b/arkindex/documents/tests/test_bulk_elements.py
index bd72c968d6a5dc89b84429976ceb960ab813d959..c47348d9853466583d235e1fd3bb26496b4427a4 100644
--- a/arkindex/documents/tests/test_bulk_elements.py
+++ b/arkindex/documents/tests/test_bulk_elements.py
@@ -71,7 +71,6 @@ class TestBulkElements(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:elements-bulk-create", kwargs={"pk": str(self.element.id)}),
             data=self.payload,
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(response.json(), {"detail": "Authentication credentials were not provided."})
@@ -83,7 +82,6 @@ class TestBulkElements(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:elements-bulk-create", kwargs={"pk": str(self.element.id)}),
             data=self.payload,
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(response.json(), {"detail": "You do not have permission to perform this action."})
@@ -95,7 +93,6 @@ class TestBulkElements(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:elements-bulk-create", kwargs={"pk": str(self.element.id)}),
             data=self.payload,
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
 
@@ -107,7 +104,6 @@ class TestBulkElements(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:elements-bulk-create", kwargs={"pk": str(self.element.id)}),
             data={"elements": []},
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -123,7 +119,6 @@ class TestBulkElements(FixtureAPITestCase):
                     "worker_run_id": str(self.local_worker_run.id),
                     "elements": [],
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"elements": {"non_field_errors": ["This list may not be empty."]}})
@@ -143,7 +138,6 @@ class TestBulkElements(FixtureAPITestCase):
                         }
                     ]
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -164,7 +158,6 @@ class TestBulkElements(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:elements-bulk-create", kwargs={"pk": str(self.element.id)}),
                 data=self.payload,
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
@@ -224,7 +217,6 @@ class TestBulkElements(FixtureAPITestCase):
                         for i in range(1, 5)
                     ]
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
@@ -249,7 +241,6 @@ class TestBulkElements(FixtureAPITestCase):
                         }
                     ]
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -272,7 +263,6 @@ class TestBulkElements(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:elements-bulk-create", kwargs={"pk": str(self.rotated_page.id)}),
             data=self.payload,
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         created_elements = Element.objects.get_descending(self.rotated_page.id)
@@ -287,7 +277,6 @@ class TestBulkElements(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:elements-bulk-create", kwargs={"pk": str(self.mirrored_page.id)}),
             data=self.payload,
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         created_elements = Element.objects.get_descending(self.mirrored_page.id)
@@ -343,7 +332,6 @@ class TestBulkElements(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:elements-bulk-create", kwargs={"pk": str(self.element.id)}),
                 data=payload,
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -369,7 +357,6 @@ class TestBulkElements(FixtureAPITestCase):
                         }
                     ]
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -393,7 +380,6 @@ class TestBulkElements(FixtureAPITestCase):
                         }
                     ]
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -410,7 +396,6 @@ class TestBulkElements(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:elements-bulk-create", kwargs={"pk": str(self.element.id)}),
                 data=payload,
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertEqual(response.json(), {"worker_run_id": [
@@ -428,7 +413,6 @@ class TestBulkElements(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:elements-bulk-create", kwargs={"pk": str(self.element.id)}),
                 data=payload,
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertEqual(response.json(), {"worker_run_id": [
@@ -452,7 +436,6 @@ class TestBulkElements(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:elements-bulk-create", kwargs={"pk": str(self.element.id)}),
                 data=payload,
-                format="json",
                 HTTP_AUTHORIZATION=f"Ponos {task.token}",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -469,7 +452,6 @@ class TestBulkElements(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:elements-bulk-create", kwargs={"pk": str(self.element.id)}),
                 data=self.payload,
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
@@ -518,7 +500,6 @@ class TestBulkElements(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:elements-bulk-create", kwargs={"pk": str(self.element.id)}),
                 data=payload,
-                format="json",
                 HTTP_AUTHORIZATION=f"Ponos {task.token}",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -565,7 +546,6 @@ class TestBulkElements(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:elements-bulk-create", kwargs={"pk": str(self.element.id)}),
                 data=payload,
-                format="json",
                 HTTP_AUTHORIZATION=f"Ponos {task.token}",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
diff --git a/arkindex/documents/tests/test_bulk_transcription_entities.py b/arkindex/documents/tests/test_bulk_transcription_entities.py
index 8359e3d4adde18846425736bfa7d9a2b6d71d0ef..fe8b103614a2c8734812064c7824b3d18c8a3bcf 100644
--- a/arkindex/documents/tests/test_bulk_transcription_entities.py
+++ b/arkindex/documents/tests/test_bulk_transcription_entities.py
@@ -63,7 +63,6 @@ class TestBulkTranscriptionEntities(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:transcription-entities-bulk", kwargs={"pk": str(self.transcription.id)}),
                 data={},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertEqual(response.json(), {
@@ -81,7 +80,6 @@ class TestBulkTranscriptionEntities(FixtureAPITestCase):
                     "entities": [],
                     "worker_run_id": str(fake_uuid),
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertEqual(response.json(), {
@@ -113,7 +111,6 @@ class TestBulkTranscriptionEntities(FixtureAPITestCase):
                     ],
                     "worker_run_id": str(self.local_worker_run.id),
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -131,7 +128,6 @@ class TestBulkTranscriptionEntities(FixtureAPITestCase):
                     ],
                     "worker_run_id": str(self.local_worker_run.id),
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -162,7 +158,6 @@ class TestBulkTranscriptionEntities(FixtureAPITestCase):
                     ],
                     "worker_run_id": str(self.local_worker_run.id),
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -191,7 +186,6 @@ class TestBulkTranscriptionEntities(FixtureAPITestCase):
                     ],
                     "worker_run_id": str(self.worker_run.id),
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -222,7 +216,6 @@ class TestBulkTranscriptionEntities(FixtureAPITestCase):
                     ],
                     "worker_run_id": str(private_worker_run.id),
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -259,7 +252,6 @@ class TestBulkTranscriptionEntities(FixtureAPITestCase):
                     ],
                     "worker_run_id": str(other_worker_run.id),
                 },
-                format="json",
                 HTTP_AUTHORIZATION=f"Ponos {task.token}",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -310,7 +302,6 @@ class TestBulkTranscriptionEntities(FixtureAPITestCase):
                     ],
                     "worker_run_id": str(self.local_worker_run.id),
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
@@ -378,7 +369,6 @@ class TestBulkTranscriptionEntities(FixtureAPITestCase):
                     ],
                     "worker_run_id": str(self.worker_run.id),
                 },
-                format="json",
                 HTTP_AUTHORIZATION=f"Ponos {task.token}",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -413,7 +403,6 @@ class TestBulkTranscriptionEntities(FixtureAPITestCase):
                     ],
                     "worker_run_id": str(self.local_worker_run.id),
                 },
-                format="json",
                 HTTP_AUTHORIZATION=f"Ponos {task.token}",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
diff --git a/arkindex/documents/tests/test_bulk_transcriptions.py b/arkindex/documents/tests/test_bulk_transcriptions.py
index b94712e37591da43bb242ae9a7d9705ffd219f5e..b1b58af420ebd46f041619d619daad1a25f39848 100644
--- a/arkindex/documents/tests/test_bulk_transcriptions.py
+++ b/arkindex/documents/tests/test_bulk_transcriptions.py
@@ -53,7 +53,7 @@ class TestBulkTranscriptions(FixtureAPITestCase):
                         "confidence": 0.4
                     }
                 ],
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertEqual(response.json(), {
             "transcriptions": [
@@ -87,7 +87,7 @@ class TestBulkTranscriptions(FixtureAPITestCase):
                         "confidence": 0.85
                     },
                 ],
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
             "worker_run_id": ["This field is required."]
@@ -106,7 +106,7 @@ class TestBulkTranscriptions(FixtureAPITestCase):
                         "text": "Sneasel"
                     },
                 ],
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertEqual(response.json(), {"transcriptions": [
             {"non_field_errors": [
@@ -139,7 +139,7 @@ class TestBulkTranscriptions(FixtureAPITestCase):
                         "confidence": 0.33
                     },
                 ],
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
         first_tr, second_tr = test_element.transcriptions.values_list("id", flat=True)
@@ -188,7 +188,7 @@ class TestBulkTranscriptions(FixtureAPITestCase):
                         "confidence": 0.33
                     },
                 ],
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertEqual(response.json(), {
             "transcriptions": [
@@ -206,7 +206,6 @@ class TestBulkTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(3):
             response = self.client.post(
                 reverse("api:transcription-bulk"),
-                format="json",
                 data={
                     "worker_run_id": str(self.worker_run.id),
                     "transcriptions": [
@@ -236,7 +235,6 @@ class TestBulkTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(3):
             response = self.client.post(
                 reverse("api:transcription-bulk"),
-                format="json",
                 data={
                     "worker_run_id": str(private_worker_run.id),
                     "transcriptions": [
@@ -272,7 +270,6 @@ class TestBulkTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(2):
             response = self.client.post(
                 reverse("api:transcription-bulk"),
-                format="json",
                 data={
                     "worker_run_id": str(other_worker_run.id),
                     "transcriptions": [
@@ -323,7 +320,7 @@ class TestBulkTranscriptions(FixtureAPITestCase):
                         "confidence": 0.12
                     },
                 ],
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
         first_tr, second_tr = element1.transcriptions.values_list("id", flat=True)
@@ -396,7 +393,6 @@ class TestBulkTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(4):
             response = self.client.post(
                 reverse("api:transcription-bulk"),
-                format="json",
                 data={
                     "worker_run_id": str(self.worker_run.id),
                     "transcriptions": [
@@ -448,7 +444,6 @@ class TestBulkTranscriptions(FixtureAPITestCase):
         with self.assertNumQueries(4):
             response = self.client.post(
                 reverse("api:transcription-bulk"),
-                format="json",
                 data={
                     "worker_run_id": str(local_worker_run.id),
                     "transcriptions": [
diff --git a/arkindex/documents/tests/test_children_elements.py b/arkindex/documents/tests/test_children_elements.py
index 9515f9b9a39888c975db5a293a0457fa558c4997..98117d29fa747ccad17a4b9c7700017950393eb9 100644
--- a/arkindex/documents/tests/test_children_elements.py
+++ b/arkindex/documents/tests/test_children_elements.py
@@ -469,7 +469,7 @@ class TestChildrenElements(FixtureAPITestCase):
                     [x + width, y],
                     [x, y]
                 ],
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_201_CREATED, response.json())
             return self.corpus.elements.get(id=response.json()["id"])
 
diff --git a/arkindex/documents/tests/test_classification.py b/arkindex/documents/tests/test_classification.py
index a8dd00e79b37ef31700517da94e2cb3d107ccc1a..35b6bda2f74d420b60a98b1937cc2a6691328d8c 100644
--- a/arkindex/documents/tests/test_classification.py
+++ b/arkindex/documents/tests/test_classification.py
@@ -70,7 +70,6 @@ class TestClassifications(FixtureAPITestCase):
                     "ml_class": str(self.text.id),
                     "worker_run_id": None,
                 },
-                format="json"
             )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
@@ -749,7 +748,6 @@ class TestClassifications(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:elements-selection"),
                 data={"ids": [self.folder.id, self.element.id, act_x.id, act_y.id]},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
@@ -824,7 +822,6 @@ class TestClassifications(FixtureAPITestCase):
         self.client.post(
             reverse("api:elements-selection"),
             data={"ids": [self.folder.id, self.element.id, act_x.id]},
-            format="json"
         )
 
         with self.assertNumQueries(4):
@@ -851,7 +848,6 @@ class TestClassifications(FixtureAPITestCase):
         self.client.post(
             reverse("api:elements-selection"),
             data={"ids": [self.folder.id, self.element.id]},
-            format="json"
         )
 
         with self.assertNumQueries(3):
diff --git a/arkindex/documents/tests/test_create_elements.py b/arkindex/documents/tests/test_create_elements.py
index 7dee5d25fa12c60e5d6b672c2190dc271bec7a59..2644b8120835a504bb685876c6c82cf7b42fbffe 100644
--- a/arkindex/documents/tests/test_create_elements.py
+++ b/arkindex/documents/tests/test_create_elements.py
@@ -562,7 +562,6 @@ class TestCreateElements(FixtureAPITestCase):
                     "image": None,
                     "polygon": None,
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
diff --git a/arkindex/documents/tests/test_create_parent_selection.py b/arkindex/documents/tests/test_create_parent_selection.py
index f60e35e3e775ee56f1697b8cf07f28981987403f..82754123b260c5497c85c4af0cda008b93172198 100644
--- a/arkindex/documents/tests/test_create_parent_selection.py
+++ b/arkindex/documents/tests/test_create_parent_selection.py
@@ -23,7 +23,7 @@ class TestMoveSelection(FixtureAPITestCase):
             response = self.client.post(reverse("api:create-parent-selection"), {
                 "corpus_id": str(self.corpus.id),
                 "parent_id": str(self.parent.id),
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
     @override_settings(ARKINDEX_FEATURES={"selection": True})
@@ -35,7 +35,7 @@ class TestMoveSelection(FixtureAPITestCase):
             response = self.client.post(reverse("api:create-parent-selection"), {
                 "corpus_id": str(self.corpus.id),
                 "parent_id": str(self.parent.id),
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
     @override_settings(ARKINDEX_FEATURES={"selection": False})
@@ -45,7 +45,7 @@ class TestMoveSelection(FixtureAPITestCase):
             response = self.client.post(reverse("api:create-parent-selection"), {
                 "corpus_id": str(self.corpus.id),
                 "parent_id": str(self.parent.id),
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
             self.assertDictEqual(
                 response.json(), {"non_field_errors": ["Selection is not available on this instance."]}
@@ -64,7 +64,7 @@ class TestMoveSelection(FixtureAPITestCase):
             response = self.client.post(reverse("api:create-parent-selection"), {
                 "corpus_id": str(private_corpus.id),
                 "parent_id": str(private_element.id),
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
             response.json(),
@@ -82,7 +82,7 @@ class TestMoveSelection(FixtureAPITestCase):
             response = self.client.post(reverse("api:create-parent-selection"), {
                 "corpus_id": str(self.corpus.id),
                 "parent_id": "12341234-1234-1234-1234-123412341234"
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
             response.json(),
@@ -97,7 +97,7 @@ class TestMoveSelection(FixtureAPITestCase):
             response = self.client.post(reverse("api:create-parent-selection"), {
                 "corpus_id": str(self.corpus.id),
                 "parent_id": str(self.page.id),
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
             response.json(),
@@ -115,7 +115,7 @@ class TestMoveSelection(FixtureAPITestCase):
             response = self.client.post(reverse("api:create-parent-selection"), {
                 "corpus_id": str(self.corpus.id),
                 "parent_id": str(parent.id),
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
             response.json(),
@@ -131,7 +131,7 @@ class TestMoveSelection(FixtureAPITestCase):
             response = self.client.post(reverse("api:create-parent-selection"), {
                 "corpus_id": str(self.corpus.id),
                 "parent_id": str(parent.id),
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
             response.json(),
@@ -148,7 +148,7 @@ class TestMoveSelection(FixtureAPITestCase):
             response = self.client.post(reverse("api:create-parent-selection"), {
                 "corpus_id": str(self.corpus.id),
                 "parent_id": str(parent_id),
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
             response.json(),
@@ -166,7 +166,7 @@ class TestMoveSelection(FixtureAPITestCase):
             response = self.client.post(reverse("api:create-parent-selection"), {
                 "corpus_id": str(self.corpus.id),
                 "parent_id": str(self.parent.id),
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
         self.assertEqual(delay_mock.call_count, 1)
diff --git a/arkindex/documents/tests/test_create_transcriptions.py b/arkindex/documents/tests/test_create_transcriptions.py
index 1800ed9d2b9e4963794577f58425104e82eb14fc..03eae8d9ac90e0fca40ad1d7a1176754131f68fa 100644
--- a/arkindex/documents/tests/test_create_transcriptions.py
+++ b/arkindex/documents/tests/test_create_transcriptions.py
@@ -36,7 +36,7 @@ class TestTranscriptionCreate(FixtureAPITestCase):
 
     def test_require_login(self):
         with self.assertNumQueries(0):
-            response = self.client.post(reverse("api:transcription-create", kwargs={"pk": self.line.id}), format="json")
+            response = self.client.post(reverse("api:transcription-create", kwargs={"pk": self.line.id}))
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(response.json(), {
             "detail": "Authentication credentials were not provided."
@@ -48,7 +48,6 @@ class TestTranscriptionCreate(FixtureAPITestCase):
         with self.assertNumQueries(3):
             response = self.client.post(
                 reverse("api:transcription-create", kwargs={"pk": self.private_page.id}),
-                format="json",
                 data={"text": "NEKUDOTAYIM"}
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
@@ -62,7 +61,6 @@ class TestTranscriptionCreate(FixtureAPITestCase):
         with self.assertNumQueries(2):
             response = self.client.post(
                 reverse("api:transcription-create", kwargs={"pk": self.private_page.id}),
-                format="json",
                 data={"text": "NEKUDOTAYIM"}
             )
             self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
@@ -72,7 +70,6 @@ class TestTranscriptionCreate(FixtureAPITestCase):
         with self.assertNumQueries(3):
             response = self.client.post(
                 reverse("api:transcription-create", kwargs={"pk": uuid4()}),
-                format="json",
                 data={"text": "NEKUDOTAYIM"}
             )
             self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
@@ -82,7 +79,6 @@ class TestTranscriptionCreate(FixtureAPITestCase):
         with self.assertNumQueries(4):
             response = self.client.post(
                 reverse("api:transcription-create", kwargs={"pk": self.line.id}),
-                format="json",
                 data={"text": "A perfect day in a perfect place"}
             )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -109,7 +105,6 @@ class TestTranscriptionCreate(FixtureAPITestCase):
         with self.assertNumQueries(4):
             response = self.client.post(
                 reverse("api:transcription-create", kwargs={"pk": self.line.id}),
-                format="json",
                 data={
                     "text": ts.text,
                 }
@@ -128,7 +123,6 @@ class TestTranscriptionCreate(FixtureAPITestCase):
         with self.assertNumQueries(4):
             response = self.client.post(
                 reverse("api:transcription-create", kwargs={"pk": self.line.id}),
-                format="json",
                 data={"text": "A perfect day in a perfect place", "orientation": "vertical-lr"}
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -151,7 +145,6 @@ class TestTranscriptionCreate(FixtureAPITestCase):
         with self.assertNumQueries(3):
             response = self.client.post(
                 reverse("api:transcription-create", kwargs={"pk": self.line.id}),
-                format="json",
                 data={"text": "A perfect day in a perfect place", "orientation": "wiggly"}
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -162,7 +155,6 @@ class TestTranscriptionCreate(FixtureAPITestCase):
         with self.assertNumQueries(4):
             response = self.client.post(
                 reverse("api:transcription-create", kwargs={"pk": self.line.id}),
-                format="json",
                 data={"text": "A classy text line"}
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -172,7 +164,6 @@ class TestTranscriptionCreate(FixtureAPITestCase):
         with self.assertNumQueries(4):
             response = self.client.post(
                 reverse("api:transcription-create", kwargs={"pk": self.line.id}),
-                format="json",
                 data={
                     "text": "NEKUDOTAYIM",
                     "worker_version": str(self.worker_version.id),
@@ -199,7 +190,6 @@ class TestTranscriptionCreate(FixtureAPITestCase):
         with self.assertNumQueries(5):
             response = self.client.post(
                 reverse("api:transcription-create", kwargs={"pk": self.line.id}),
-                format="json",
                 data={
                     "text": "NEKUDOTAYIM",
                     "worker_run_id": str(self.local_worker_run.id),
@@ -236,7 +226,6 @@ class TestTranscriptionCreate(FixtureAPITestCase):
         with self.assertNumQueries(4):
             response = self.client.post(
                 reverse("api:transcription-create", kwargs={"pk": self.line.id}),
-                format="json",
                 data={
                     "text": "NEKUDOTAYIM",
                     "worker_run_id": str(local_worker_run.id),
@@ -271,7 +260,6 @@ class TestTranscriptionCreate(FixtureAPITestCase):
         with self.assertNumQueries(4):
             response = self.client.post(
                 reverse("api:transcription-create", kwargs={"pk": self.line.id}),
-                format="json",
                 data={
                     "text": "NEKUDOTAYIM",
                     "worker_run_id": str(self.worker_run.id),
@@ -304,7 +292,6 @@ class TestTranscriptionCreate(FixtureAPITestCase):
         with self.assertNumQueries(4):
             response = self.client.post(
                 reverse("api:transcription-create", kwargs={"pk": self.line.id}),
-                format="json",
                 data={
                     "text": "NEKUDOTAYIM",
                     "worker_run_id": str(self.worker_run.id),
@@ -327,7 +314,6 @@ class TestTranscriptionCreate(FixtureAPITestCase):
         with self.assertNumQueries(4):
             response = self.client.post(
                 reverse("api:transcription-create", kwargs={"pk": self.line.id}),
-                format="json",
                 data={
                     "text": "NEKUDOTAYIM",
                     "worker_run_id": str(worker_run.id),
@@ -356,7 +342,6 @@ class TestTranscriptionCreate(FixtureAPITestCase):
         with self.assertNumQueries(3):
             response = self.client.post(
                 reverse("api:transcription-create", kwargs={"pk": self.line.id}),
-                format="json",
                 data={
                     "text": "NEKUDOTAYIM",
                     "worker_run_id": str(other_worker_run.id),
@@ -375,7 +360,6 @@ class TestTranscriptionCreate(FixtureAPITestCase):
         with self.assertNumQueries(4):
             response = self.client.post(
                 reverse("api:transcription-create", kwargs={"pk": self.line.id}),
-                format="json",
                 data={
                     "text": "NEKUDOTAYIM",
                     "worker_run_id": "aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa",
@@ -393,7 +377,6 @@ class TestTranscriptionCreate(FixtureAPITestCase):
         with self.assertNumQueries(4):
             response = self.client.post(
                 reverse("api:transcription-create", kwargs={"pk": self.line.id}),
-                format="json",
                 data={
                     "text": "CIRCLE",
                     "worker_run_id": str(self.local_worker_run.id),
@@ -414,7 +397,6 @@ class TestTranscriptionCreate(FixtureAPITestCase):
         with self.assertNumQueries(4):
             response = self.client.post(
                 reverse("api:transcription-create", kwargs={"pk": null_zone_page.id}),
-                format="json",
                 data={
                     "text": "ELLIPSE",
                     "confidence": .42
@@ -439,7 +421,6 @@ class TestTranscriptionCreate(FixtureAPITestCase):
         with self.assertNumQueries(5):
             response = self.client.post(
                 reverse("api:transcription-create", kwargs={"pk": self.line.id}),
-                format="json",
                 data={
                     "text": "CIRCLE",
                     "type": "paragraph",
diff --git a/arkindex/documents/tests/test_edit_transcriptions.py b/arkindex/documents/tests/test_edit_transcriptions.py
index 92093e9a04dcfc026cbdc6c3bc93840b0db30185..b41e80b70639620b72c893cd60ea6286d8807227 100644
--- a/arkindex/documents/tests/test_edit_transcriptions.py
+++ b/arkindex/documents/tests/test_edit_transcriptions.py
@@ -95,7 +95,6 @@ class TestEditTranscription(FixtureAPITestCase):
         self.client.force_login(self.user)
         response = self.client.patch(
             reverse("api:transcription-edit", kwargs={"pk": self.manual_transcription.id}),
-            format="json",
             data={"text": "Once upon a time in a castle"}
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
@@ -108,7 +107,6 @@ class TestEditTranscription(FixtureAPITestCase):
         self.client.force_login(self.user)
         response = self.client.patch(
             reverse("api:transcription-edit", kwargs={"pk": self.ml_transcription.id}),
-            format="json",
             data={"text": "Once upon a time in a castle"}
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
@@ -124,7 +122,6 @@ class TestEditTranscription(FixtureAPITestCase):
         manual_tr_id = self.manual_transcription.id
         response = self.client.patch(
             reverse("api:transcription-edit", kwargs={"pk": manual_tr_id}),
-            format="json",
             data={
                 "id": uuid4(),
                 "text": "a knight was living lonely",
@@ -153,7 +150,6 @@ class TestEditTranscription(FixtureAPITestCase):
         manual_tr_id = self.manual_transcription.id
         response = self.client.patch(
             reverse("api:transcription-edit", kwargs={"pk": manual_tr_id}),
-            format="json",
             data={
                 "orientation": "vertical-rl"
             }
@@ -176,7 +172,6 @@ class TestEditTranscription(FixtureAPITestCase):
         manual_tr_id = self.manual_transcription.id
         response = self.client.patch(
             reverse("api:transcription-edit", kwargs={"pk": manual_tr_id}),
-            format="json",
             data={
                 "orientation": "wobbly"
             }
@@ -192,7 +187,6 @@ class TestEditTranscription(FixtureAPITestCase):
         self.client.force_login(self.private_read_user)
         response = self.client.patch(
             reverse("api:transcription-edit", kwargs={"pk": self.private_transcription.id}),
-            format="json",
             data={"text": "He was good and fearless"}
         )
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
@@ -208,7 +202,6 @@ class TestEditTranscription(FixtureAPITestCase):
         self.client.force_login(self.write_user)
         response = self.client.patch(
             reverse("api:transcription-edit", kwargs={"pk": self.ml_transcription.id}),
-            format="json",
             data={"text": "He used to play the Bumbulum"}
         )
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
@@ -224,7 +217,6 @@ class TestEditTranscription(FixtureAPITestCase):
         self.manual_transcription.transcription_entities.create(entity=self.entity, offset=0, length=1)
         response = self.client.patch(
             reverse("api:transcription-edit", kwargs={"pk": self.manual_transcription.id}),
-            format="json",
             data={"text": "One day, the king told him to go save a princess"}
         )
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
@@ -237,7 +229,6 @@ class TestEditTranscription(FixtureAPITestCase):
         manual_tr_id = self.manual_transcription.id
         response = self.client.put(
             reverse("api:transcription-edit", kwargs={"pk": manual_tr_id}),
-            format="json",
             data={
                 "text": "a knight was living lonely",
                 "orientation": "vertical-rl",
@@ -258,7 +249,6 @@ class TestEditTranscription(FixtureAPITestCase):
         self.client.force_login(self.user)
         response = self.client.put(
             reverse("api:transcription-edit", kwargs={"pk": self.ml_transcription.id}),
-            format="json",
             data={"text": "Once upon a time in a castle", "orientation": "horizontal-rl"}
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
@@ -274,7 +264,6 @@ class TestEditTranscription(FixtureAPITestCase):
         manual_tr_id = self.manual_transcription.id
         response = self.client.put(
             reverse("api:transcription-edit", kwargs={"pk": manual_tr_id}),
-            format="json",
             data={
                 "text": "a knight was living lonely",
                 "orientation": "wobbly",
@@ -291,7 +280,6 @@ class TestEditTranscription(FixtureAPITestCase):
         self.client.force_login(self.private_read_user)
         response = self.client.put(
             reverse("api:transcription-edit", kwargs={"pk": self.private_transcription.id}),
-            format="json",
             data={"text": "He used to play the Bumbulum", "orientation": "horizontal-lr"}
         )
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
@@ -307,7 +295,6 @@ class TestEditTranscription(FixtureAPITestCase):
         self.client.force_login(self.write_user)
         response = self.client.put(
             reverse("api:transcription-edit", kwargs={"pk": self.ml_transcription.id}),
-            format="json",
             data={"text": "He used to play the Bumbulum", "orientation": "horizontal-lr"}
         )
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
@@ -323,7 +310,6 @@ class TestEditTranscription(FixtureAPITestCase):
         self.manual_transcription.transcription_entities.create(entity=self.entity, offset=0, length=1)
         response = self.client.put(
             reverse("api:transcription-edit", kwargs={"pk": self.manual_transcription.id}),
-            format="json",
             data={"text": "One day, the king told him to go save a princess"}
         )
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
diff --git a/arkindex/documents/tests/test_element_paths_api.py b/arkindex/documents/tests/test_element_paths_api.py
index 290d2ce63ee22a2c9874b1f6cffd460156fe9f05..29bcd793cf20a292c35363d60644fb81250e92f7 100644
--- a/arkindex/documents/tests/test_element_paths_api.py
+++ b/arkindex/documents/tests/test_element_paths_api.py
@@ -214,7 +214,7 @@ class TestElementsAPI(FixtureAPITestCase):
                     [x + width, y],
                     [x, y]
                 ],
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_201_CREATED, response.json())
             return self.corpus.elements.get(id=response.json()["id"])
 
diff --git a/arkindex/documents/tests/test_element_type.py b/arkindex/documents/tests/test_element_type.py
index 37d2882b3c70a74f5e32a8a567f426f538dc6e67..f9270ebd08e2d1ecdef8e4ce175451259c48ddb0 100644
--- a/arkindex/documents/tests/test_element_type.py
+++ b/arkindex/documents/tests/test_element_type.py
@@ -22,7 +22,7 @@ class TestElementType(FixtureAPITestCase):
             "corpus": self.corpus.id,
             "slug": "New_element_type",
             "display_name": "New element type",
-        }, format="json")
+        })
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
     @patch("arkindex.users.managers.BaseACLManager.filter_rights", return_value=Corpus.objects.none())
@@ -32,7 +32,7 @@ class TestElementType(FixtureAPITestCase):
             "corpus": self.private_corpus.id,
             "slug": "New_element_type",
             "display_name": "New element type",
-        }, format="json")
+        })
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
         self.assertEqual(filter_rights_mock.call_count, 1)
@@ -44,7 +44,7 @@ class TestElementType(FixtureAPITestCase):
             "corpus": self.corpus.id,
             "slug": self.element_type.slug,
             "display_name": "New element type",
-        }, format="json")
+        })
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
     def test_create(self):
@@ -54,7 +54,7 @@ class TestElementType(FixtureAPITestCase):
                 "corpus": self.corpus.id,
                 "slug": "New_element_type",
                 "display_name": "New element type",
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         data = response.json()
         self.assertIn("id", data)
@@ -79,7 +79,7 @@ class TestElementType(FixtureAPITestCase):
                 "slug": "New_element_type",
                 "display_name": "New element type",
                 "color": "d90dc4"
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         data = response.json()
         self.assertIn("id", data)
@@ -125,7 +125,6 @@ class TestElementType(FixtureAPITestCase):
                         "display_name": "New element type",
                         "color": color
                     },
-                    format="json"
                 )
                 self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
             self.assertDictEqual(response.json(), {"color": errors})
@@ -138,7 +137,7 @@ class TestElementType(FixtureAPITestCase):
                 "slug": "New_element_type",
                 "display_name": "New element type",
                 "color": "FF0000"
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         self.assertEqual(response.json()["color"], "FF0000")
 
@@ -146,7 +145,7 @@ class TestElementType(FixtureAPITestCase):
         response = self.client.post(reverse("api:element-type", kwargs={"pk": self.element_type.id}), {
             "slug": "New_element_type",
             "display_name": "New element type",
-        }, format="json")
+        })
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
     @patch("arkindex.users.managers.BaseACLManager.filter_rights", return_value=Corpus.objects.none())
@@ -157,7 +156,7 @@ class TestElementType(FixtureAPITestCase):
         response = self.client.patch(reverse("api:element-type", kwargs={"pk": private_element_type.id}), {
             "slug": "New_element_type",
             "display_name": "New element type",
-        }, format="json")
+        })
         self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
 
         self.assertEqual(filter_rights_mock.call_count, 1)
@@ -168,7 +167,7 @@ class TestElementType(FixtureAPITestCase):
         self.client.force_login(self.superuser)
         response = self.client.patch(reverse("api:element-type", kwargs={"pk": self.element_type.id}), {
             "slug": element_type.slug,
-        }, format="json")
+        })
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"slug": ["Slug must be unique"]})
 
@@ -177,7 +176,7 @@ class TestElementType(FixtureAPITestCase):
         with self.assertNumQueries(3):
             response = self.client.patch(
                 reverse("api:element-type", kwargs={"pk": self.element_type.id}),
-                {"color": "chouquette"}, format="json"
+                {"color": "chouquette"},
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"color": [
@@ -190,7 +189,7 @@ class TestElementType(FixtureAPITestCase):
         with self.assertNumQueries(3):
             response = self.client.patch(
                 reverse("api:element-type", kwargs={"pk": self.element_type.id}),
-                {"color": "yellow"}, format="json"
+                {"color": "yellow"},
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"color": [
@@ -221,7 +220,6 @@ class TestElementType(FixtureAPITestCase):
                 response = self.client.patch(
                     reverse("api:element-type", kwargs={"pk": self.element_type.id}),
                     update_data,
-                    format="json"
                 )
                 self.assertEqual(response.status_code, status.HTTP_200_OK)
                 data = response.json()
@@ -242,7 +240,7 @@ class TestElementType(FixtureAPITestCase):
         response = self.client.post(reverse("api:element-type", kwargs={"pk": self.element_type.id}), {
             "slug": "New_element_type",
             "display_name": "New element type",
-        }, format="json")
+        })
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
     @patch("arkindex.users.managers.BaseACLManager.filter_rights", return_value=Corpus.objects.none())
@@ -253,7 +251,7 @@ class TestElementType(FixtureAPITestCase):
         response = self.client.put(reverse("api:element-type", kwargs={"pk": private_element_type.id}), {
             "slug": "New_element_type",
             "display_name": "New element type",
-        }, format="json")
+        })
         self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
 
         self.assertEqual(filter_rights_mock.call_count, 1)
@@ -265,7 +263,7 @@ class TestElementType(FixtureAPITestCase):
         response = self.client.put(reverse("api:element-type", kwargs={"pk": self.element_type.id}), {
             "slug": element_type.slug,
             "display_name": "New element type",
-        }, format="json")
+        })
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"slug": ["Slug must be unique"]})
 
@@ -279,7 +277,6 @@ class TestElementType(FixtureAPITestCase):
                     "display_name": "New element type",
                     "color": "chouquette"
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"color": [
@@ -294,7 +291,7 @@ class TestElementType(FixtureAPITestCase):
                 "slug": "New_element_type",
                 "display_name": "New element type",
                 "color": "yellow"
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"color": [
             "Color should be a hexadecimal color code"
@@ -307,7 +304,7 @@ class TestElementType(FixtureAPITestCase):
                 "slug": "New_element_type",
                 "display_name": "New element type",
                 "color": "4287f5"
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_200_OK)
         data = response.json()
         self.element_type.refresh_from_db()
diff --git a/arkindex/documents/tests/test_entities_api.py b/arkindex/documents/tests/test_entities_api.py
index 70a84274e6fd3af28b85a1c7dab8a85264d0cf8c..6e04b648c00fad0207252da57cb1421879538131 100644
--- a/arkindex/documents/tests/test_entities_api.py
+++ b/arkindex/documents/tests/test_entities_api.py
@@ -192,7 +192,7 @@ class TestEntitiesAPI(FixtureAPITestCase):
         }
         self.client.force_login(self.user)
         with self.assertNumQueries(3):
-            response = self.client.post(reverse("api:entity-create"), data=data, format="json")
+            response = self.client.post(reverse("api:entity-create"), data=data)
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"type_id": ["“location” is not a valid UUID."]})
 
@@ -208,7 +208,7 @@ class TestEntitiesAPI(FixtureAPITestCase):
         }
         self.client.force_login(self.user)
         with self.assertNumQueries(4):
-            response = self.client.post(reverse("api:entity-create"), data=data, format="json")
+            response = self.client.post(reverse("api:entity-create"), data=data)
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"type_id": ['Invalid pk "aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa" - object does not exist.']})
 
@@ -225,7 +225,7 @@ class TestEntitiesAPI(FixtureAPITestCase):
         }
         self.client.force_login(self.user)
         with self.assertNumQueries(4):
-            response = self.client.post(reverse("api:entity-create"), data=data, format="json")
+            response = self.client.post(reverse("api:entity-create"), data=data)
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"type_id": [f"EntityType {str(extraneous_type.id)} does not exist in corpus Unit Tests."]})
 
@@ -240,7 +240,7 @@ class TestEntitiesAPI(FixtureAPITestCase):
         }
         self.client.force_login(self.user)
         with self.assertNumQueries(3):
-            response = self.client.post(reverse("api:entity-create"), data=data, format="json")
+            response = self.client.post(reverse("api:entity-create"), data=data)
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"type_id": ["This field is required."]})
 
@@ -255,7 +255,7 @@ class TestEntitiesAPI(FixtureAPITestCase):
             },
         }
         with self.assertNumQueries(0):
-            response = self.client.post(reverse("api:entity-create"), data=data, format="json")
+            response = self.client.post(reverse("api:entity-create"), data=data)
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
     def test_create_entity_worker_version_ignored(self):
@@ -274,7 +274,7 @@ class TestEntitiesAPI(FixtureAPITestCase):
         }
         self.client.force_login(self.user)
         with self.assertNumQueries(5):
-            response = self.client.post(reverse("api:entity-create"), data=data, format="json")
+            response = self.client.post(reverse("api:entity-create"), data=data)
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
         data = response.json()
@@ -300,7 +300,7 @@ class TestEntitiesAPI(FixtureAPITestCase):
         }
         self.client.force_login(self.user)
         with self.assertNumQueries(5):
-            response = self.client.post(reverse("api:entity-create"), data=data, format="json")
+            response = self.client.post(reverse("api:entity-create"), data=data)
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"worker_run_id": ['Invalid pk "aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa" - object does not exist.']})
 
@@ -312,7 +312,6 @@ class TestEntitiesAPI(FixtureAPITestCase):
         with self.assertNumQueries(5):
             response = self.client.post(
                 reverse("api:entity-create"),
-                format="json",
                 data={
                     "name": "test",
                     "type_id": str(self.person_type.id),
@@ -340,7 +339,6 @@ class TestEntitiesAPI(FixtureAPITestCase):
         with self.assertNumQueries(5):
             response = self.client.post(
                 reverse("api:entity-create"),
-                format="json",
                 data={
                     "name": "test",
                     "type_id": str(self.person_type.id),
@@ -366,7 +364,6 @@ class TestEntitiesAPI(FixtureAPITestCase):
         with self.assertNumQueries(5):
             response = self.client.post(
                 reverse("api:entity-create"),
-                format="json",
                 data={
                     "name": "test",
                     "type_id": str(self.person_type.id),
@@ -398,7 +395,6 @@ class TestEntitiesAPI(FixtureAPITestCase):
         with self.assertNumQueries(4):
             response = self.client.post(
                 reverse("api:entity-create"),
-                format="json",
                 data={
                     "name": "Bunnelby",
                     "type_id": str(self.person_type.id),
@@ -430,7 +426,7 @@ class TestEntitiesAPI(FixtureAPITestCase):
         }
         self.client.force_login(self.user)
         with self.assertNumQueries(6):
-            response = self.client.post(reverse("api:entity-create"), data=data, format="json")
+            response = self.client.post(reverse("api:entity-create"), data=data)
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
         data = response.json()
@@ -481,7 +477,6 @@ class TestEntitiesAPI(FixtureAPITestCase):
         with self.assertNumQueries(5):
             response = self.client.post(
                 reverse("api:entity-create"),
-                format="json",
                 data={
                     "name": "test",
                     "type_id": str(self.person_type.id),
@@ -516,7 +511,6 @@ class TestEntitiesAPI(FixtureAPITestCase):
         with self.assertNumQueries(5):
             response = self.client.post(
                 reverse("api:entity-create"),
-                format="json",
                 data={
                     "name": "Bunnelby",
                     "type_id": str(self.person_type.id),
@@ -543,7 +537,6 @@ class TestEntitiesAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:transcription-entity-create", kwargs={"pk": str(self.transcription.id)}),
                 data=self.tr_entities_sample,
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         transcription_entity = TranscriptionEntity.objects.get(
@@ -570,7 +563,6 @@ class TestEntitiesAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:transcription-entity-create", kwargs={"pk": str(self.transcription.id)}),
                 data=self.tr_entities_confidence_sample,
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         transcription_entity = TranscriptionEntity.objects.get(
@@ -597,7 +589,6 @@ class TestEntitiesAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:transcription-entity-create", kwargs={"pk": str(self.transcription.id)}),
                 data=self.tr_entities_sample,
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
@@ -615,7 +606,6 @@ class TestEntitiesAPI(FixtureAPITestCase):
                     "length": 8,
                     "worker_run_id": str(self.local_worker_run.id),
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         self.assertDictEqual(response.json(), {
@@ -640,7 +630,6 @@ class TestEntitiesAPI(FixtureAPITestCase):
                     "length": 8,
                     "worker_run_id": "aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa",
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -658,7 +647,6 @@ class TestEntitiesAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:transcription-entity-create", kwargs={"pk": str(self.transcription.id)}),
                 data=self.tr_entities_sample,
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -681,7 +669,6 @@ class TestEntitiesAPI(FixtureAPITestCase):
                     "offset": 4,
                     "length": 0
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
@@ -700,7 +687,6 @@ class TestEntitiesAPI(FixtureAPITestCase):
                     "length": 1,
                     "confidence": 2.0
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
@@ -719,7 +705,6 @@ class TestEntitiesAPI(FixtureAPITestCase):
                     "length": 1,
                     "confidence": -0.5
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
@@ -744,7 +729,6 @@ class TestEntitiesAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:transcription-entity-create", kwargs={"pk": str(self.transcription.id)}),
                 data=self.tr_entities_sample,
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -769,7 +753,6 @@ class TestEntitiesAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:transcription-entity-create", kwargs={"pk": str(self.transcription.id)}),
                 data=self.tr_entities_sample,
-                format="json"
             )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -799,7 +782,6 @@ class TestEntitiesAPI(FixtureAPITestCase):
                     "length": 8,
                     "worker_run_id": str(self.local_worker_run.id),
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -814,7 +796,6 @@ class TestEntitiesAPI(FixtureAPITestCase):
         with self.assertNumQueries(5):
             response = self.client.post(
                 reverse("api:transcription-entity-create", kwargs={"pk": str(self.transcription.id)}),
-                format="json",
                 data={
                     "entity": str(self.entity.id),
                     "offset": 4,
@@ -839,7 +820,6 @@ class TestEntitiesAPI(FixtureAPITestCase):
         with self.assertNumQueries(5):
             response = self.client.post(
                 reverse("api:transcription-entity-create", kwargs={"pk": str(self.transcription.id)}),
-                format="json",
                 data={
                     "entity": str(self.entity.id),
                     "offset": 4,
@@ -870,7 +850,6 @@ class TestEntitiesAPI(FixtureAPITestCase):
         with self.assertNumQueries(4):
             response = self.client.post(
                 reverse("api:transcription-entity-create", kwargs={"pk": str(self.transcription.id)}),
-                format="json",
                 data={
                     "entity": str(self.entity.id),
                     "offset": 4,
@@ -897,7 +876,6 @@ class TestEntitiesAPI(FixtureAPITestCase):
         with self.assertNumQueries(6):
             response = self.client.post(
                 reverse("api:transcription-entity-create", kwargs={"pk": str(self.transcription.id)}),
-                format="json",
                 data={
                     "entity": str(self.entity.id),
                     "offset": 4,
@@ -932,7 +910,6 @@ class TestEntitiesAPI(FixtureAPITestCase):
         with self.assertNumQueries(6):
             response = self.client.post(
                 reverse("api:transcription-entity-create", kwargs={"pk": str(self.transcription.id)}),
-                format="json",
                 data={
                     "entity": str(self.entity.id),
                     "offset": 4,
@@ -974,7 +951,6 @@ class TestEntitiesAPI(FixtureAPITestCase):
                     "offset": 4,
                     "length": 8,
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         transcription_entity = self.transcription.transcription_entities.filter(worker_run=None, entity=self.entity).get()
@@ -997,7 +973,6 @@ class TestEntitiesAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:transcription-entity-create", kwargs={"pk": str(self.transcription.id)}),
                 data=data,
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
diff --git a/arkindex/documents/tests/test_entity_types.py b/arkindex/documents/tests/test_entity_types.py
index 9348ee6dcce7e8d4b384d9da94728d74cc16cc19..3646aaf9a173549dc53fd06628e42e0f3111ab7c 100644
--- a/arkindex/documents/tests/test_entity_types.py
+++ b/arkindex/documents/tests/test_entity_types.py
@@ -39,7 +39,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
             "name": "dagger one"
         }
         with self.assertNumQueries(0):
-            response = self.client.post(reverse("api:entity-type-create"), data=data, format="json")
+            response = self.client.post(reverse("api:entity-type-create"), data=data)
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
     def test_create_requires_verified(self):
@@ -49,7 +49,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
             "name": "dagger one"
         }
         with self.assertNumQueries(2):
-            response = self.client.post(reverse("api:entity-type-create"), data=data, format="json")
+            response = self.client.post(reverse("api:entity-type-create"), data=data)
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(
             response.json(),
@@ -66,7 +66,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
         self.assertEqual(self.private_corpus.entity_types.all().count(), 1)
 
         with self.assertNumQueries(2):
-            response = self.client.post(reverse("api:entity-type-create"), data=data, format="json")
+            response = self.client.post(reverse("api:entity-type-create"), data=data)
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
         self.assertDictEqual(
@@ -86,7 +86,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
         }
         self.assertEqual(self.private_corpus.entity_types.all().count(), 1)
         with self.assertNumQueries(5):
-            response = self.client.post(reverse("api:entity-type-create"), data=data, format="json")
+            response = self.client.post(reverse("api:entity-type-create"), data=data)
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         self.assertEqual(self.private_corpus.entity_types.all().count(), 2)
         self.assertEqual(response.json()["color"], "ff0000")
@@ -121,7 +121,6 @@ class TestEntityTypesAPI(FixtureAPITestCase):
                         "name": "dagger spare",
                         "color": color
                     },
-                    format="json"
                 )
                 self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
             self.assertDictEqual(response.json(), {"color": errors})
@@ -134,7 +133,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
             "color": "FF0000"
         }
         with self.assertNumQueries(5):
-            response = self.client.post(reverse("api:entity-type-create"), data=data, format="json")
+            response = self.client.post(reverse("api:entity-type-create"), data=data)
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         self.assertEqual(response.json()["color"], "FF0000")
 
@@ -147,7 +146,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
         }
         self.assertEqual(self.private_corpus.entity_types.all().count(), 1)
         with self.assertNumQueries(5):
-            response = self.client.post(reverse("api:entity-type-create"), data=data, format="json")
+            response = self.client.post(reverse("api:entity-type-create"), data=data)
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         self.assertEqual(self.private_corpus.entity_types.all().count(), 2)
         self.assertEqual(response.json()["color"], "f76719")
@@ -162,7 +161,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
             "color": "f76719"
         }
         with self.assertNumQueries(4):
-            response = self.client.post(reverse("api:entity-type-create"), data=data, format="json")
+            response = self.client.post(reverse("api:entity-type-create"), data=data)
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"name": ["Entity Type with name some type already exists in corpus private."]})
 
@@ -174,7 +173,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
             "color": "f76719"
         }
         with self.assertNumQueries(0):
-            response = self.client.put(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), data=data, format="json")
+            response = self.client.put(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), data=data)
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
     def test_update_requires_verified(self):
@@ -184,7 +183,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
             "color": "f76719"
         }
         with self.assertNumQueries(2):
-            response = self.client.put(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), data=data, format="json")
+            response = self.client.put(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), data=data)
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(
             response.json(),
@@ -200,7 +199,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
         }
 
         with self.assertNumQueries(4):
-            response = self.client.put(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), data=data, format="json")
+            response = self.client.put(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), data=data)
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
         self.assertDictEqual(
@@ -221,7 +220,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
             "color": "f76719"
         }
         with self.assertNumQueries(6):
-            response = self.client.put(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), data=data, format="json")
+            response = self.client.put(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), data=data)
             self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.private_corpus_entity_type.refresh_from_db()
         self.assertEqual(self.private_corpus_entity_type.color, "f76719")
@@ -235,7 +234,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
             "color": "f76719"
         }
         with self.assertNumQueries(5):
-            response = self.client.put(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), data=data, format="json")
+            response = self.client.put(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), data=data)
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"name": ["Entity Type with name dagger spare already exists in corpus private."]})
 
@@ -245,7 +244,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
             "color": "f76719"
         }
         with self.assertNumQueries(4):
-            response = self.client.put(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), data=data, format="json")
+            response = self.client.put(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), data=data)
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"name": ["This field is required."]})
 
@@ -256,7 +255,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
             "name": "iceman"
         }
         with self.assertNumQueries(4):
-            response = self.client.put(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), data=data, format="json")
+            response = self.client.put(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), data=data)
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"corpus": ["It is not possible to update an Entity Type's corpus."]})
 
@@ -268,7 +267,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
             "color": "f76719"
         }
         with self.assertNumQueries(0):
-            response = self.client.patch(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), data=data, format="json")
+            response = self.client.patch(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), data=data)
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
     def test_partial_update_requires_verified(self):
@@ -278,7 +277,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
             "color": "f76719"
         }
         with self.assertNumQueries(2):
-            response = self.client.patch(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), data=data, format="json")
+            response = self.client.patch(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), data=data)
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(
             response.json(),
@@ -294,7 +293,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
         }
 
         with self.assertNumQueries(4):
-            response = self.client.patch(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), data=data, format="json")
+            response = self.client.patch(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), data=data)
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
         self.assertDictEqual(
@@ -315,7 +314,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
             "color": "f76719"
         }
         with self.assertNumQueries(6):
-            response = self.client.patch(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), data=data, format="json")
+            response = self.client.patch(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), data=data)
             self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.assertEqual(response.json()["color"], "f76719")
         self.assertEqual(response.json()["name"], "dagger spare")
@@ -326,7 +325,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
             "color": "f76719"
         }
         with self.assertNumQueries(6):
-            response = self.client.patch(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), data=data, format="json")
+            response = self.client.patch(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), data=data)
             self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.private_corpus_entity_type.refresh_from_db()
         self.assertEqual(self.private_corpus_entity_type.color, "f76719")
@@ -338,7 +337,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
             "corpus": str(self.corpus.id),
         }
         with self.assertNumQueries(4):
-            response = self.client.patch(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), data=data, format="json")
+            response = self.client.patch(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), data=data)
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"corpus": ["It is not possible to update an Entity Type's corpus."]})
 
@@ -346,7 +345,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
 
     def test_retrieve_does_not_require_login_public_project(self):
         with self.assertNumQueries(1):
-            response = self.client.get(reverse("api:entity-type-details", kwargs={"pk": self.location_type.id}), format="json")
+            response = self.client.get(reverse("api:entity-type-details", kwargs={"pk": self.location_type.id}))
             self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.assertDictEqual(response.json(), {
             "id": str(self.location_type.id),
@@ -360,7 +359,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
         self.client.force_login(self.no_access)
 
         with self.assertNumQueries(2):
-            response = self.client.get(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), format="json")
+            response = self.client.get(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}))
             self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
 
         self.assertDictEqual(
@@ -374,7 +373,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
     def test_retrieve(self):
         self.client.force_login(self.private_corpus_guest)
         with self.assertNumQueries(3):
-            response = self.client.get(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), format="json")
+            response = self.client.get(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}))
             self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.assertEqual(response.json()["color"], "ff0000")
         self.assertEqual(response.json()["name"], "some type")
@@ -385,7 +384,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
     def test_delete_requires_corpus_admin(self, has_access_mock):
         self.client.force_login(self.user)
         with self.assertNumQueries(4):
-            response = self.client.delete(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), format="json")
+            response = self.client.delete(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}))
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(
             response.json(),
@@ -398,7 +397,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
     def test_delete(self):
         self.client.force_login(self.private_corpus_admin)
         with self.assertNumQueries(6):
-            response = self.client.delete(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), format="json")
+            response = self.client.delete(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}))
             self.assertEqual(response.status_code, status.HTTP_204_NO_CONTENT)
         with self.assertRaises(EntityType.DoesNotExist):
             self.private_corpus_entity_type.refresh_from_db()
@@ -407,7 +406,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
         Entity.objects.create(type=self.private_corpus_entity_type, corpus=self.private_corpus, name="bob")
         self.client.force_login(self.private_corpus_admin)
         with self.assertNumQueries(5):
-            response = self.client.delete(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}), format="json")
+            response = self.client.delete(reverse("api:entity-type-details", kwargs={"pk": self.private_corpus_entity_type.id}))
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"detail": ["Some entities are using this entity type."]})
 
@@ -415,7 +414,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
 
     def test_list_does_not_require_login_public_project(self):
         with self.assertNumQueries(3):
-            response = self.client.get(reverse("api:corpus-entity-types", kwargs={"pk": self.corpus.id}), format="json")
+            response = self.client.get(reverse("api:corpus-entity-types", kwargs={"pk": self.corpus.id}))
             self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.assertCountEqual(response.json()["results"], [
             {
@@ -449,7 +448,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
     def test_list_requires_guest_private_project(self, has_access_mock):
         self.client.force_login(self.no_access)
         with self.assertNumQueries(3):
-            response = self.client.get(reverse("api:corpus-entity-types", kwargs={"pk": self.private_corpus.id}), format="json")
+            response = self.client.get(reverse("api:corpus-entity-types", kwargs={"pk": self.private_corpus.id}))
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
         self.assertEqual(has_access_mock.call_count, 1)
@@ -460,7 +459,7 @@ class TestEntityTypesAPI(FixtureAPITestCase):
         type_3 = EntityType.objects.create(corpus=self.private_corpus, color="29d911", name="person")
         self.client.force_login(self.private_corpus_guest)
         with self.assertNumQueries(5):
-            response = self.client.get(reverse("api:corpus-entity-types", kwargs={"pk": self.private_corpus.id}), format="json")
+            response = self.client.get(reverse("api:corpus-entity-types", kwargs={"pk": self.private_corpus.id}))
             self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.assertCountEqual(response.json()["results"], [
             {
diff --git a/arkindex/documents/tests/test_metadata.py b/arkindex/documents/tests/test_metadata.py
index cff728b7e96384ba45ecaaff9b1d0845b47e3f50..52ce577ee58d90ca8318d19f3a479ce3854e8dd8 100644
--- a/arkindex/documents/tests/test_metadata.py
+++ b/arkindex/documents/tests/test_metadata.py
@@ -324,7 +324,6 @@ class TestMetaData(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:element-metadata", kwargs={"pk": str(self.vol.id)}),
             data={"type": "location", "name": "location", "value": "Texas", "worker_run_id": non_existent_worker_run_id},
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"worker_run_id": [f'Invalid pk "{non_existent_worker_run_id}" - object does not exist.']})
@@ -1062,7 +1061,6 @@ class TestMetaData(FixtureAPITestCase):
         response = self.client.patch(
             reverse("api:metadata-edit", kwargs={"pk": str(metadata.id)}),
             data={"entity_id": None},
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK, response.json())
         metadata.refresh_from_db()
@@ -1279,7 +1277,6 @@ class TestMetaData(FixtureAPITestCase):
                     "worker_run_id": str(self.worker_run.id),
                     "metadata_list": [{"type": "text", "name": "language", "value": "Japanese"}],
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
 
@@ -1304,7 +1301,6 @@ class TestMetaData(FixtureAPITestCase):
                         {"type": "numeric", "name": "numeric", "value": "42", "entity_id": str(entity.id)}
                     ]
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         self.assertEqual(self.vol.metadatas.count(), 4)  # 1 added during setUp
@@ -1361,7 +1357,6 @@ class TestMetaData(FixtureAPITestCase):
                     {"type": "text", "name": "language", "value": "Chinese"},
                     {"type": "text", "name": "alt_language", "value": "Mandarin"}
                 ]},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -1377,7 +1372,6 @@ class TestMetaData(FixtureAPITestCase):
                 {"type": "text", "name": "language", "value": "Chinese"},
                 {"type": "text", "name": "alt_language", "value": "Mandarin"}
             ], "worker_run_id": non_existent_worker_run_id},
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"worker_run_id": [f'Invalid pk "{non_existent_worker_run_id}" - object does not exist.']})
@@ -1396,7 +1390,6 @@ class TestMetaData(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:element-metadata-bulk", kwargs={"pk": str(self.vol.id)}),
             data={"metadata_list": []},
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -1418,7 +1411,6 @@ class TestMetaData(FixtureAPITestCase):
                         {"type": "text", "name": "edition", "value": "Hammersmith"},
                     ]
                 },
-                format="json",
                 HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -1444,7 +1436,6 @@ class TestMetaData(FixtureAPITestCase):
                         {"type": "text", "name": "edition", "value": "Hammersmith"},
                     ]
                 },
-                format="json",
                 HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -1476,7 +1467,6 @@ class TestMetaData(FixtureAPITestCase):
                         {"type": "text", "name": "edition", "value": "Hammersmith"},
                     ]
                 },
-                format="json",
                 HTTP_AUTHORIZATION=f"Ponos {task.token}",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -1493,7 +1483,6 @@ class TestMetaData(FixtureAPITestCase):
                     "id": "aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa",
                 },
                 ], "worker_run_id": str(self.local_worker_run.id)},
-                format="json"
             )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         md = self.vol.metadatas.get(type=MetaType.Text, name="language")
@@ -1518,7 +1507,6 @@ class TestMetaData(FixtureAPITestCase):
                         {"type": "location", "name": "not allowed", "value": "boo"},
                     ]
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         self.assertEqual(self.vol.metadatas.count(), 2)
@@ -1575,7 +1563,6 @@ class TestMetaData(FixtureAPITestCase):
                         {"type": "location", "name": "not allowed", "value": "boo"},
                     ]
                 },
-                format="json",
                 HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -1630,7 +1617,6 @@ class TestMetaData(FixtureAPITestCase):
                         {"type": "location", "name": "location", "value": "Texas"}
                     ]
                 },
-                format="json",
             )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -1656,7 +1642,6 @@ class TestMetaData(FixtureAPITestCase):
                         {"type": "location", "name": "location", "value": "Texas"}
                     ]
                 },
-                format="json",
             )
         self.assertEqual(response_2.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response_2.json(), {
@@ -1681,7 +1666,6 @@ class TestMetaData(FixtureAPITestCase):
                         {"type": "text", "name": "edition", "value": "Hammersmith"},
                     ]
                 },
-                format="json",
                 HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
diff --git a/arkindex/documents/tests/test_move_element.py b/arkindex/documents/tests/test_move_element.py
index d667bd311f7b4f4ce5c6040a6c06e90f555f2340..15f218083f466b277fb66442fa0380bc9f37230b 100644
--- a/arkindex/documents/tests/test_move_element.py
+++ b/arkindex/documents/tests/test_move_element.py
@@ -18,7 +18,7 @@ class TestMoveElement(FixtureAPITestCase):
 
     def test_move_element_requires_login(self):
         with self.assertNumQueries(0):
-            response = self.client.post(reverse("api:move-element"), {"source": str(self.source.id), "destination": str(self.destination.id)}, format="json")
+            response = self.client.post(reverse("api:move-element"), {"source": str(self.source.id), "destination": str(self.destination.id)})
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
     def test_move_element_requires_verified(self):
@@ -26,7 +26,7 @@ class TestMoveElement(FixtureAPITestCase):
         self.user.save()
         self.client.force_login(self.user)
         with self.assertNumQueries(2):
-            response = self.client.post(reverse("api:move-element"), {"source": str(self.source.id), "destination": str(self.destination.id)}, format="json")
+            response = self.client.post(reverse("api:move-element"), {"source": str(self.source.id), "destination": str(self.destination.id)})
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
     @patch("arkindex.users.managers.BaseACLManager.filter_rights", return_value=Corpus.objects.none())
@@ -38,7 +38,7 @@ class TestMoveElement(FixtureAPITestCase):
 
         self.client.force_login(self.user)
         with self.assertNumQueries(2):
-            response = self.client.post(reverse("api:move-element"), {"source": str(private_element.id), "destination": str(private_element.id)}, format="json")
+            response = self.client.post(reverse("api:move-element"), {"source": str(private_element.id), "destination": str(private_element.id)})
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
             response.json(),
@@ -51,7 +51,7 @@ class TestMoveElement(FixtureAPITestCase):
     def test_move_element_wrong_source(self):
         self.client.force_login(self.user)
         with self.assertNumQueries(4):
-            response = self.client.post(reverse("api:move-element"), {"source": "12341234-1234-1234-1234-123412341234", "destination": str(self.destination.id)}, format="json")
+            response = self.client.post(reverse("api:move-element"), {"source": "12341234-1234-1234-1234-123412341234", "destination": str(self.destination.id)})
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
             response.json(),
@@ -61,7 +61,7 @@ class TestMoveElement(FixtureAPITestCase):
     def test_move_element_wrong_destination(self):
         self.client.force_login(self.user)
         with self.assertNumQueries(4):
-            response = self.client.post(reverse("api:move-element"), {"source": str(self.source.id), "destination": "12341234-1234-1234-1234-123412341234"}, format="json")
+            response = self.client.post(reverse("api:move-element"), {"source": str(self.source.id), "destination": "12341234-1234-1234-1234-123412341234"})
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
             response.json(),
@@ -71,7 +71,7 @@ class TestMoveElement(FixtureAPITestCase):
     def test_move_element_same_source_destination(self):
         self.client.force_login(self.user)
         with self.assertNumQueries(4):
-            response = self.client.post(reverse("api:move-element"), {"source": str(self.source.id), "destination": str(self.source.id)}, format="json")
+            response = self.client.post(reverse("api:move-element"), {"source": str(self.source.id), "destination": str(self.source.id)})
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
             response.json(),
@@ -85,7 +85,7 @@ class TestMoveElement(FixtureAPITestCase):
 
         self.client.force_login(self.user)
         with self.assertNumQueries(4):
-            response = self.client.post(reverse("api:move-element"), {"source": str(self.source.id), "destination": str(destination.id)}, format="json")
+            response = self.client.post(reverse("api:move-element"), {"source": str(self.source.id), "destination": str(destination.id)})
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
             response.json(),
@@ -97,7 +97,7 @@ class TestMoveElement(FixtureAPITestCase):
 
         self.client.force_login(self.user)
         with self.assertNumQueries(5):
-            response = self.client.post(reverse("api:move-element"), {"source": str(self.source.id), "destination": str(destination.id)}, format="json")
+            response = self.client.post(reverse("api:move-element"), {"source": str(self.source.id), "destination": str(destination.id)})
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
             response.json(),
@@ -110,7 +110,7 @@ class TestMoveElement(FixtureAPITestCase):
 
         self.client.force_login(self.user)
         with self.assertNumQueries(6):
-            response = self.client.post(reverse("api:move-element"), {"source": str(source.id), "destination": str(destination_id)}, format="json")
+            response = self.client.post(reverse("api:move-element"), {"source": str(source.id), "destination": str(destination_id)})
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
             response.json(),
@@ -121,7 +121,7 @@ class TestMoveElement(FixtureAPITestCase):
     def test_move_element(self, delay_mock):
         self.client.force_login(self.user)
         with self.assertNumQueries(6):
-            response = self.client.post(reverse("api:move-element"), {"source": str(self.source.id), "destination": str(self.destination.id)}, format="json")
+            response = self.client.post(reverse("api:move-element"), {"source": str(self.source.id), "destination": str(self.destination.id)})
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
         self.assertEqual(delay_mock.call_count, 1)
diff --git a/arkindex/documents/tests/test_move_selection.py b/arkindex/documents/tests/test_move_selection.py
index d524373efef234c5c5b7c9f82aa9f9d80698e86b..d63f4bd35e4a9b70f2d3632fd75280828b4d52f6 100644
--- a/arkindex/documents/tests/test_move_selection.py
+++ b/arkindex/documents/tests/test_move_selection.py
@@ -20,7 +20,7 @@ class TestMoveSelection(FixtureAPITestCase):
     @override_settings(ARKINDEX_FEATURES={"selection": True})
     def test_move_selection_requires_login(self):
         with self.assertNumQueries(0):
-            response = self.client.post(reverse("api:move-selection"), {"corpus_id": str(self.corpus.id), "destination": str(self.destination.id)}, format="json")
+            response = self.client.post(reverse("api:move-selection"), {"corpus_id": str(self.corpus.id), "destination": str(self.destination.id)})
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
     @override_settings(ARKINDEX_FEATURES={"selection": True})
@@ -29,14 +29,14 @@ class TestMoveSelection(FixtureAPITestCase):
         self.user.save()
         self.client.force_login(self.user)
         with self.assertNumQueries(2):
-            response = self.client.post(reverse("api:move-selection"), {"corpus_id": str(self.corpus.id), "destination": str(self.destination.id)}, format="json")
+            response = self.client.post(reverse("api:move-selection"), {"corpus_id": str(self.corpus.id), "destination": str(self.destination.id)})
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
     @override_settings(ARKINDEX_FEATURES={"selection": False})
     def test_move_selection_disabled(self):
         self.client.force_login(self.user)
         with self.assertNumQueries(4):
-            response = self.client.post(reverse("api:move-selection"), {"corpus_id": str(self.corpus.id), "destination": str(self.destination.id)}, format="json")
+            response = self.client.post(reverse("api:move-selection"), {"corpus_id": str(self.corpus.id), "destination": str(self.destination.id)})
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
             self.assertDictEqual(
                 response.json(), {"non_field_errors": ["Selection is not available on this instance."]}
@@ -52,7 +52,7 @@ class TestMoveSelection(FixtureAPITestCase):
 
         self.client.force_login(self.user)
         with self.assertNumQueries(2):
-            response = self.client.post(reverse("api:move-selection"), {"corpus_id": str(private_corpus.id), "destination": str(private_element.id)}, format="json")
+            response = self.client.post(reverse("api:move-selection"), {"corpus_id": str(private_corpus.id), "destination": str(private_element.id)})
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
             response.json(),
@@ -67,7 +67,7 @@ class TestMoveSelection(FixtureAPITestCase):
         self.client.force_login(self.user)
         self.user.selected_elements.add(self.page)
         with self.assertNumQueries(4):
-            response = self.client.post(reverse("api:move-selection"), {"corpus_id": str(self.corpus.id), "destination": "12341234-1234-1234-1234-123412341234"}, format="json")
+            response = self.client.post(reverse("api:move-selection"), {"corpus_id": str(self.corpus.id), "destination": "12341234-1234-1234-1234-123412341234"})
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
             response.json(),
@@ -79,7 +79,7 @@ class TestMoveSelection(FixtureAPITestCase):
         self.client.force_login(self.user)
         self.user.selected_elements.add(self.page)
         with self.assertNumQueries(6):
-            response = self.client.post(reverse("api:move-selection"), {"corpus_id": str(self.corpus.id), "destination": str(self.page.id)}, format="json")
+            response = self.client.post(reverse("api:move-selection"), {"corpus_id": str(self.corpus.id), "destination": str(self.page.id)})
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
             response.json(),
@@ -94,7 +94,7 @@ class TestMoveSelection(FixtureAPITestCase):
         self.client.force_login(self.user)
         self.user.selected_elements.add(self.page)
         with self.assertNumQueries(5):
-            response = self.client.post(reverse("api:move-selection"), {"corpus_id": str(self.corpus.id), "destination": str(destination.id)}, format="json")
+            response = self.client.post(reverse("api:move-selection"), {"corpus_id": str(self.corpus.id), "destination": str(destination.id)})
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
             response.json(),
@@ -107,7 +107,7 @@ class TestMoveSelection(FixtureAPITestCase):
         self.client.force_login(self.user)
         self.user.selected_elements.add(self.page)
         with self.assertNumQueries(7):
-            response = self.client.post(reverse("api:move-selection"), {"corpus_id": str(self.corpus.id), "destination": str(destination.id)}, format="json")
+            response = self.client.post(reverse("api:move-selection"), {"corpus_id": str(self.corpus.id), "destination": str(destination.id)})
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
             response.json(),
@@ -121,7 +121,7 @@ class TestMoveSelection(FixtureAPITestCase):
         self.client.force_login(self.user)
         self.user.selected_elements.add(target)
         with self.assertNumQueries(8):
-            response = self.client.post(reverse("api:move-selection"), {"corpus_id": str(self.corpus.id), "destination": str(destination_id)}, format="json")
+            response = self.client.post(reverse("api:move-selection"), {"corpus_id": str(self.corpus.id), "destination": str(destination_id)})
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
             response.json(),
@@ -136,7 +136,7 @@ class TestMoveSelection(FixtureAPITestCase):
         another_page = self.corpus.elements.get(name="Volume 1, page 1v")
         self.user.selected_elements.add(another_page)
         with self.assertNumQueries(8):
-            response = self.client.post(reverse("api:move-selection"), {"corpus_id": str(self.corpus.id), "destination": str(self.destination.id)}, format="json")
+            response = self.client.post(reverse("api:move-selection"), {"corpus_id": str(self.corpus.id), "destination": str(self.destination.id)})
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
         self.assertEqual(delay_mock.call_count, 1)
diff --git a/arkindex/documents/tests/test_patch_elements.py b/arkindex/documents/tests/test_patch_elements.py
index 18354726d1096af6170f6a11fded0dd688d30a3e..5f3a37f73503a0430445c686483d5696557d3915 100644
--- a/arkindex/documents/tests/test_patch_elements.py
+++ b/arkindex/documents/tests/test_patch_elements.py
@@ -49,7 +49,6 @@ class TestPatchElements(FixtureAPITestCase):
         response = self.client.patch(
             reverse("api:element-retrieve", kwargs={"pk": str(self.vol.id)}),
             data={"name": "Untitled (2)"},
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(
@@ -66,7 +65,6 @@ class TestPatchElements(FixtureAPITestCase):
         response = self.client.patch(
             reverse("api:element-retrieve", kwargs={"pk": str(self.private_elt.id)}),
             data={"name": "Untitled (2)"},
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(
@@ -86,7 +84,6 @@ class TestPatchElements(FixtureAPITestCase):
         response = self.client.patch(
             reverse("api:element-retrieve", kwargs={"pk": str(self.private_elt.id)}),
             data={"name": "Untitled (2)"},
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
 
@@ -99,7 +96,6 @@ class TestPatchElements(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:element-retrieve", kwargs={"pk": str(self.vol.id)}),
                 data={"name": "Untitled (2)"},
-                format="json",
             )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.assertEqual(response.json()["name"], "Untitled (2)")
@@ -127,7 +123,6 @@ class TestPatchElements(FixtureAPITestCase):
                 "classifications": [],
                 "worker_run": str(WorkerRun.objects.first().id),
             },
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
         data = response.json()
@@ -151,7 +146,6 @@ class TestPatchElements(FixtureAPITestCase):
             data={
                 "polygon": [[10, 20], [10, 30], [30, 30], [30, 20], [10, 20]]
             },
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.assertEqual(response.json()["name"], self.element.name)
@@ -172,7 +166,6 @@ class TestPatchElements(FixtureAPITestCase):
             data={
                 "polygon": [[10, 20], [10, 30], [30, 30], [30, 20], [10, 20]]
             },
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -188,7 +181,6 @@ class TestPatchElements(FixtureAPITestCase):
             data={
                 "image": str(self.image.id),
             },
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.line_2.refresh_from_db()
@@ -204,7 +196,6 @@ class TestPatchElements(FixtureAPITestCase):
                 "image": str(self.image.id),
                 "polygon": [[10, 20], [10, 30], [30, 30], [30, 20], [10, 20]],
             },
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.vol.refresh_from_db()
@@ -229,7 +220,6 @@ class TestPatchElements(FixtureAPITestCase):
                 "image": str(bad_image.id),
                 "polygon": [[10, 20], [10, 30], [30, 30], [30, 20], [10, 20]],
             },
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"image": ["This image does not have valid dimensions."]})
@@ -242,7 +232,6 @@ class TestPatchElements(FixtureAPITestCase):
             data={
                 "polygon": [[-10, -20], [10, 30], [30, 30], [30, 20], [10, 20]]
             },
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -261,7 +250,6 @@ class TestPatchElements(FixtureAPITestCase):
             data={
                 "polygon": [[0, 1009], [10, 30], [30, 30], [30, 20], [10, 20]]
             },
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
diff --git a/arkindex/documents/tests/test_put_elements.py b/arkindex/documents/tests/test_put_elements.py
index babf90c77922d61621d8ac7c1d1287c1497d00ea..ec14c406921da715a4fccc005a48f07c5fb98231 100644
--- a/arkindex/documents/tests/test_put_elements.py
+++ b/arkindex/documents/tests/test_put_elements.py
@@ -42,7 +42,6 @@ class TestPutElements(FixtureAPITestCase):
         response = self.client.put(
             reverse("api:element-retrieve", kwargs={"pk": str(self.vol.id)}),
             data={"name": "Untitled (2)"},
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(
@@ -57,7 +56,6 @@ class TestPutElements(FixtureAPITestCase):
         response = self.client.put(
             reverse("api:element-retrieve", kwargs={"pk": str(self.private_elt.id)}),
             data={"name": "Untitled (2)"},
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(
@@ -76,7 +74,6 @@ class TestPutElements(FixtureAPITestCase):
         response = self.client.put(
             reverse("api:element-retrieve", kwargs={"pk": str(self.private_elt.id)}),
             data={"name": "Untitled (2)"},
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
 
@@ -91,7 +88,6 @@ class TestPutElements(FixtureAPITestCase):
             response = self.client.put(
                 reverse("api:element-retrieve", kwargs={"pk": str(self.vol.id)}),
                 data={"name": "Untitled (2)", "type": "text_line"},
-                format="json",
             )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
         data = response.json()
@@ -122,7 +118,6 @@ class TestPutElements(FixtureAPITestCase):
                 "classifications": [],
                 "worker_run": str(WorkerRun.objects.first().id),
             },
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
         data = response.json()
@@ -148,7 +143,6 @@ class TestPutElements(FixtureAPITestCase):
                 "type": "text_line",
                 "polygon": [[10, 20], [10, 30], [30, 30], [30, 20], [10, 20]]
             },
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.assertEqual(response.json()["name"], "Untitled (2)")
@@ -173,7 +167,6 @@ class TestPutElements(FixtureAPITestCase):
                 "type": "text_line",
                 "polygon": [[10, 20], [10, 30], [30, 30], [30, 20], [10, 20]]
             },
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -191,7 +184,6 @@ class TestPutElements(FixtureAPITestCase):
                 "type": "text_line",
                 "image": str(self.image.id),
             },
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.element.refresh_from_db()
@@ -209,7 +201,6 @@ class TestPutElements(FixtureAPITestCase):
                 "image": str(self.image.id),
                 "polygon": [[10, 20], [10, 30], [30, 30], [30, 20], [10, 20]],
             },
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.vol.refresh_from_db()
@@ -236,7 +227,6 @@ class TestPutElements(FixtureAPITestCase):
                 "image": str(bad_image.id),
                 "polygon": [[10, 20], [10, 30], [30, 30], [30, 20], [10, 20]],
             },
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"image": ["This image does not have valid dimensions."]})
@@ -251,7 +241,6 @@ class TestPutElements(FixtureAPITestCase):
                 "type": "text_line",
                 "polygon": [[-10, -20], [10, 30], [30, 30], [30, 20], [10, 20]]
             },
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -272,7 +261,6 @@ class TestPutElements(FixtureAPITestCase):
                 "type": "text_line",
                 "polygon": [[10, 20], [10, 30], [30, 30], [3000, 2000], [10, 20]]
             },
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
diff --git a/arkindex/documents/tests/test_selection_api.py b/arkindex/documents/tests/test_selection_api.py
index d2fc1d7bda25f8561c1c55895950aabdba46a089..4e0bdd59b49bd36575c3e2e80637c0affc76cb44 100644
--- a/arkindex/documents/tests/test_selection_api.py
+++ b/arkindex/documents/tests/test_selection_api.py
@@ -29,7 +29,6 @@ class TestSelectionAPI(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:elements-selection"),
             data={"ids": [self.vol.id]},
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
@@ -40,7 +39,6 @@ class TestSelectionAPI(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:elements-selection"),
             data={"ids": [self.vol.id]},
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
@@ -50,7 +48,6 @@ class TestSelectionAPI(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:elements-selection"),
             data={"ids": [self.vol.id]},
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertListEqual(response.json(), ["Selection is not available on this instance."])
@@ -69,7 +66,6 @@ class TestSelectionAPI(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:elements-selection"),
             data={"ids": [element.id]},
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -83,7 +79,6 @@ class TestSelectionAPI(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:elements-selection"),
             data={"ids": [self.vol.id, "ffffffff-ffff-ffff-ffff-ffffffffffff"]},
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -95,7 +90,6 @@ class TestSelectionAPI(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:elements-selection"),
             data={"ids": [self.vol.id, "oh no"]},
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertContains(response, "Must be a valid UUID", count=1, status_code=400)
@@ -105,7 +99,6 @@ class TestSelectionAPI(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:elements-selection"),
             data={"ids": [self.vol.id, self.page.id, self.vol.id]},
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         selected = self.client.get(reverse("api:elements-selection")).json()["results"]
@@ -128,7 +121,6 @@ class TestSelectionAPI(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:elements-selection"),
             data={"ids": [self.vol.id]},
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         results = response.json()
@@ -143,7 +135,6 @@ class TestSelectionAPI(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:elements-selection"),
             data={"ids": [self.vol.id, self.page.id]},
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         results = response.json()
@@ -165,7 +156,6 @@ class TestSelectionAPI(FixtureAPITestCase):
         self.client.post(
             reverse("api:elements-selection"),
             data={"ids": [self.vol.id]},
-            format="json"
         )
         response = self.client.delete(reverse("api:elements-selection"), data={"id": self.page.id})
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
@@ -177,7 +167,6 @@ class TestSelectionAPI(FixtureAPITestCase):
         self.client.post(
             reverse("api:elements-selection"),
             data={"ids": [self.vol.id]},
-            format="json"
         )
         response = self.client.delete(reverse("api:elements-selection"), data={"id": self.page.id})
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
@@ -187,14 +176,13 @@ class TestSelectionAPI(FixtureAPITestCase):
         self.client.post(
             reverse("api:elements-selection"),
             data={"ids": [self.vol.id]},
-            format="json"
         )
         response = self.client.delete(reverse("api:elements-selection"), data={"id": self.page.id})
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
     def test_delete_not_a_uuid(self):
         self.client.force_login(self.user)
-        response = self.client.delete(reverse("api:elements-selection"), data={"id": {"id": self.page.id, "type": "page"}}, format="json")
+        response = self.client.delete(reverse("api:elements-selection"), data={"id": {"id": self.page.id, "type": "page"}})
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertEqual(response.json(), {"id": ["Not a valid UUID."]})
 
@@ -210,7 +198,6 @@ class TestSelectionAPI(FixtureAPITestCase):
         self.client.post(
             reverse("api:elements-selection"),
             data={"ids": [self.vol.id, self.page.id]},
-            format="json"
         )
         response = self.client.get(reverse("api:elements-selection"))
         self.assertEqual(response.status_code, status.HTTP_200_OK)
@@ -269,7 +256,6 @@ class TestSelectionAPI(FixtureAPITestCase):
         self.client.post(
             reverse("api:elements-selection"),
             data={"ids": [self.vol.id]},
-            format="json"
         )
         response = self.client.get(reverse("api:elements-selection"))
         self.assertEqual(response.status_code, status.HTTP_200_OK)
@@ -284,7 +270,6 @@ class TestSelectionAPI(FixtureAPITestCase):
         self.client.post(
             reverse("api:elements-selection"),
             data={"ids": [self.page.id]},
-            format="json"
         )
         response = self.client.get(reverse("api:elements-selection"))
         self.assertEqual(response.status_code, status.HTTP_200_OK)
@@ -297,7 +282,6 @@ class TestSelectionAPI(FixtureAPITestCase):
         self.client.post(
             reverse("api:elements-selection"),
             data={"ids": [self.vol.id, self.page.id]},
-            format="json"
         )
         response = self.client.get(reverse("api:elements-selection"))
         self.assertEqual(response.status_code, status.HTTP_200_OK)
diff --git a/arkindex/images/tests/test_image_api.py b/arkindex/images/tests/test_image_api.py
index edbeb945c12a910c501a4e0dd17d71b97602827d..f54a8b443e2c457408dea56d6c0b800972f36c51 100644
--- a/arkindex/images/tests/test_image_api.py
+++ b/arkindex/images/tests/test_image_api.py
@@ -716,7 +716,7 @@ class TestImageApi(FixtureAPITestCase):
 
     def test_create_image_information_bad_content(self):
         self.client.force_login(self.superuser)
-        response = self.client.post(reverse("api:iiif-info-create"), [], format="json")
+        response = self.client.post(reverse("api:iiif-info-create"), [])
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"detail": ["Payload should be a JSON object"]})
 
diff --git a/arkindex/process/tests/test_create_process.py b/arkindex/process/tests/test_create_process.py
index 8ebe63a0a72c0608156dc7d40de257cdda1e4300..6126e7f720c8abc5bf64c1da22645767723c7bec 100644
--- a/arkindex/process/tests/test_create_process.py
+++ b/arkindex/process/tests/test_create_process.py
@@ -80,7 +80,6 @@ class TestCreateProcess(FixtureAPITestCase):
                 "element_type": "page",
                 "load_children": True,
             },
-            format="json",
         )
 
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -135,7 +134,6 @@ class TestCreateProcess(FixtureAPITestCase):
                 "load_children": True,
                 "use_cache": True,
             },
-            format="json"
         )
 
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -171,7 +169,6 @@ class TestCreateProcess(FixtureAPITestCase):
                 "corpus": str(self.corpus.id),
                 "element": str(self.pages.first().id),
             },
-            format="json"
         )
 
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -180,12 +177,12 @@ class TestCreateProcess(FixtureAPITestCase):
         self.assertEqual(process.element, self.pages.first())
 
     def test_create_process_requires_login(self):
-        response = self.client.post(reverse("api:corpus-process"), {}, format="json")
+        response = self.client.post(reverse("api:corpus-process"), {})
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
     def test_create_process_required_fields(self):
         self.client.force_login(self.user)
-        response = self.client.post(reverse("api:corpus-process"), {}, format="json")
+        response = self.client.post(reverse("api:corpus-process"), {})
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
             response.json(),
@@ -205,7 +202,6 @@ class TestCreateProcess(FixtureAPITestCase):
                 "corpus": str(self.corpus.id),
                 "name": "Test",
             },
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"corpus": ["You do not have an admin access to this corpus."]})
@@ -222,7 +218,6 @@ class TestCreateProcess(FixtureAPITestCase):
                 "corpus": str(self.private_corpus.id),
                 "name": "Test",
             },
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"corpus": ["Corpus with this ID does not exist."]})
@@ -238,7 +233,6 @@ class TestCreateProcess(FixtureAPITestCase):
                 "corpus": str(self.corpus.id),
                 "element_name_contains": self.pages.first().name[2:5],
             },
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         data = response.json()
@@ -255,7 +249,6 @@ class TestCreateProcess(FixtureAPITestCase):
                 "element_name_contains": "B" * 300,
                 "element_type": "C" * 100,
             },
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -272,7 +265,6 @@ class TestCreateProcess(FixtureAPITestCase):
                 "corpus": str(self.corpus.id),
                 "element_type": "volume",
             },
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         data = response.json()
@@ -292,7 +284,6 @@ class TestCreateProcess(FixtureAPITestCase):
                 "element_type": "volume",
                 "element_name_contains": "ahahah",
             },
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         data = response.json()
@@ -310,7 +301,6 @@ class TestCreateProcess(FixtureAPITestCase):
                 "corpus": str(self.corpus.id),
                 "selection": True,
             },
-            format="json"
         )
         mixin = SelectionMixin()
         mixin.request = namedtuple("Request", "user")(self.user)
@@ -331,7 +321,6 @@ class TestCreateProcess(FixtureAPITestCase):
                 "corpus": str(self.corpus.id),
                 "element_type": "arachnid",
             },
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -350,7 +339,6 @@ class TestCreateProcess(FixtureAPITestCase):
                 "element": str(self.pages.first().id),
                 "type": "page",
             },
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
@@ -363,7 +351,6 @@ class TestCreateProcess(FixtureAPITestCase):
                     "corpus": str(self.corpus.id),
                     "ml_class_id": str(self.ml_class.id),
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
@@ -401,7 +388,6 @@ class TestCreateProcess(FixtureAPITestCase):
                     "corpus": str(self.corpus.id),
                     "element": str(element.id),
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         process = Process.objects.get(element=element, mode=ProcessMode.Workers)
@@ -449,7 +435,6 @@ class TestCreateProcess(FixtureAPITestCase):
                 "element": str(self.volume.id),
                 "selection": True,
             },
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
@@ -466,7 +451,6 @@ class TestCreateProcess(FixtureAPITestCase):
         self.client.post(
             reverse("api:elements-selection"),
             data={"ids": [page.id]},
-            format="json"
         )
         response = self.client.post(
             reverse("api:corpus-process"),
@@ -474,7 +458,6 @@ class TestCreateProcess(FixtureAPITestCase):
                 "corpus": str(self.corpus.id),
                 "selection": True,
             },
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         data = response.json()
@@ -512,7 +495,6 @@ class TestCreateProcess(FixtureAPITestCase):
                 "corpus": str(self.corpus.id),
                 "selection": True,
             },
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"selection": ["Selection is not available on this instance."]})
@@ -525,7 +507,6 @@ class TestCreateProcess(FixtureAPITestCase):
                 "corpus": str(self.corpus.id),
                 "name": "blah",
             },
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         data = response.json()
@@ -727,7 +708,6 @@ class TestCreateProcess(FixtureAPITestCase):
                 response = self.client.post(
                     reverse("api:corpus-process"),
                     data,
-                    format="json"
                 )
                 self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
@@ -763,7 +743,6 @@ class TestCreateProcess(FixtureAPITestCase):
                     "mode": "dataset",
                     "selection": True
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -783,7 +762,6 @@ class TestCreateProcess(FixtureAPITestCase):
                         "corpus": str(self.corpus.id),
                         "mode": mode,
                     },
-                    format="json"
                 )
                 self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
                 self.assertDictEqual(response.json(), {"mode": [f'"{mode}" is not a valid choice.']})
diff --git a/arkindex/process/tests/test_processes.py b/arkindex/process/tests/test_processes.py
index 0b463412c1c753c7ddb7c0a5691b88a33006bd77..eceab04504b310ad6cb858837d79ef7cc53bf27e 100644
--- a/arkindex/process/tests/test_processes.py
+++ b/arkindex/process/tests/test_processes.py
@@ -922,7 +922,6 @@ class TestProcesses(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:process-details", kwargs={"pk": self.elts_process.id}),
                 {"element_name_contains": "something"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"__all__": ["Cannot edit a process while it is running"]})
@@ -939,7 +938,6 @@ class TestProcesses(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:process-details", kwargs={"pk": self.elts_process.id}),
                 {"name": "newName"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.elts_process.refresh_from_db()
@@ -967,7 +965,6 @@ class TestProcesses(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:process-details", kwargs={"pk": process.id}),
                 {"element_id": str(element.id)},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -1006,7 +1003,6 @@ class TestProcesses(FixtureAPITestCase):
                     response = self.client.patch(
                         reverse("api:process-details", kwargs={"pk": self.elts_process.id}),
                         {"state": "stopping"},
-                        format="json",
                     )
                     self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -1026,7 +1022,6 @@ class TestProcesses(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:process-details", kwargs={"pk": self.elts_process.id}),
                 {"state": "stopping"},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -1050,7 +1045,6 @@ class TestProcesses(FixtureAPITestCase):
                     response = self.client.patch(
                         reverse("api:process-details", kwargs={"pk": self.elts_process.id}),
                         {"state": state.value},
-                        format="json",
                     )
                     self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -1078,7 +1072,6 @@ class TestProcesses(FixtureAPITestCase):
                     response = self.client.patch(
                         reverse("api:process-details", kwargs={"pk": self.elts_process.id}),
                         {"state": "stopping"},
-                        format="json",
                     )
                     self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -1117,7 +1110,6 @@ class TestProcesses(FixtureAPITestCase):
                         "element_type": "page",
                         "load_children": True
                     },
-                    format="json"
                 )
                 self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
                 self.assertDictEqual(
@@ -1144,7 +1136,6 @@ class TestProcesses(FixtureAPITestCase):
                     "load_children": True,
                     "state": "stopping",
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -1175,7 +1166,6 @@ class TestProcesses(FixtureAPITestCase):
                             "load_children": True,
                             "state": state.value,
                         },
-                        format="json",
                     )
                     self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -1210,7 +1200,6 @@ class TestProcesses(FixtureAPITestCase):
                             "load_children": True,
                             "state": "stopping",
                         },
-                        format="json",
                     )
                     self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -1244,7 +1233,6 @@ class TestProcesses(FixtureAPITestCase):
                     "load_children": True,
                     "template_id": None,
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -1277,7 +1265,6 @@ class TestProcesses(FixtureAPITestCase):
                         "load_children": True,
                         "template_id": None,
                     },
-                    format="json"
                 )
                 self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
                 self.assertDictEqual(response.json(), {
@@ -1316,7 +1303,6 @@ class TestProcesses(FixtureAPITestCase):
                     "started": "2038-01-19T03:14:08Z",
                     "finished": "2038-01-19T03:14:08Z",
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -1369,7 +1355,6 @@ class TestProcesses(FixtureAPITestCase):
                 response = self.client.patch(
                     reverse("api:process-details", kwargs={"pk": process.id}),
                     {"element_name_contains": "something"},
-                    format="json",
                 )
                 self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
                 self.assertDictEqual(
@@ -1402,7 +1387,6 @@ class TestProcesses(FixtureAPITestCase):
                     {
                         "name": "newName"
                     },
-                    format="json"
                 )
                 self.assertEqual(response.status_code, status.HTTP_200_OK)
                 process.refresh_from_db()
@@ -1442,7 +1426,6 @@ class TestProcesses(FixtureAPITestCase):
                     "ml_class_id": str(self.ml_class.id),
                     "load_children": True,
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -1472,7 +1455,6 @@ class TestProcesses(FixtureAPITestCase):
                 "element_type": None,
                 "load_children": False
             },
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
         process.refresh_from_db()
@@ -1487,7 +1469,6 @@ class TestProcesses(FixtureAPITestCase):
         response = self.client.patch(
             reverse("api:process-details", kwargs={"pk": process.id}),
             {"element_type": "unexisting_type"},
-            format="json"
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertEqual(
@@ -1512,7 +1493,6 @@ class TestProcesses(FixtureAPITestCase):
                     {
                         "ml_class_id": str(ml_class_id),
                     },
-                    format="json"
                 )
                 self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
                 self.assertDictEqual(response.json(), {
@@ -1550,7 +1530,6 @@ class TestProcesses(FixtureAPITestCase):
                     "started": "2038-01-19T03:14:08Z",
                     "finished": "2038-01-19T03:14:08Z",
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -1827,7 +1806,7 @@ class TestProcesses(FixtureAPITestCase):
             "files": [str(self.img_df.id)],
             "folder_type": "volume",
             "element_type": "page",
-        }, format="json")
+        })
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
     def test_from_files(self):
@@ -1842,7 +1821,7 @@ class TestProcesses(FixtureAPITestCase):
                 "files": [str(self.img_df.id)],
                 "folder_type": "volume",
                 "element_type": "page",
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
         data = response.json()
@@ -1867,7 +1846,7 @@ class TestProcesses(FixtureAPITestCase):
                 "files": [str(self.pdf_df.id)],
                 "folder_type": "volume",
                 "element_type": "page",
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         data = response.json()
         process = Process.objects.get(id=data["id"])
@@ -1884,7 +1863,7 @@ class TestProcesses(FixtureAPITestCase):
                 "files": [str(self.iiif_df.id)],
                 "folder_type": "volume",
                 "element_type": "page",
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
         data = response.json()
@@ -1918,7 +1897,7 @@ class TestProcesses(FixtureAPITestCase):
                 "mode": "files",
                 "folder_type": "volume",
                 "element_type": "page",
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
         data = response.json()
@@ -1943,7 +1922,7 @@ class TestProcesses(FixtureAPITestCase):
                 "files": [str(self.bad_df.id)],
                 "folder_type": "volume",
                 "element_type": "page",
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
         self.assertEqual(response.json(), {"non_field_errors": ["File imports can only import images, PDF documents, ZIP archives or IIIF manifests"]})
@@ -1958,7 +1937,7 @@ class TestProcesses(FixtureAPITestCase):
                 "folder_type": "volume",
                 "element_type": "page",
                 "mode": "easy"
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         data = response.json()
         process = Process.objects.get(id=data["id"])
@@ -1978,7 +1957,6 @@ class TestProcesses(FixtureAPITestCase):
                     "folder_type": "volume",
                     "element_type": "page",
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         data = response.json()
@@ -1997,7 +1975,6 @@ class TestProcesses(FixtureAPITestCase):
                     "folder_id": str(volume.id),
                     "element_type": "page",
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"folder_type": ["This field is required."]})
@@ -2008,7 +1985,7 @@ class TestProcesses(FixtureAPITestCase):
             "files": [],
             "folder_type": "volume",
             "element_type": "page",
-        }, format="json")
+        })
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
     def test_from_files_farm(self):
@@ -2025,7 +2002,7 @@ class TestProcesses(FixtureAPITestCase):
                 "folder_type": "volume",
                 "element_type": "page",
                 "farm_id": str(farm.id),
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
         data = response.json()
@@ -2047,7 +2024,7 @@ class TestProcesses(FixtureAPITestCase):
                 "files": [str(self.img_df.id)],
                 "folder_type": "volume",
                 "element_type": "page",
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
         data = response.json()
@@ -2068,7 +2045,7 @@ class TestProcesses(FixtureAPITestCase):
                 "folder_type": "volume",
                 "element_type": "page",
                 "farm_id": str(Farm.objects.first().id),
-            }, format="json")
+            })
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
         self.assertEqual(response.json(), {
diff --git a/arkindex/process/tests/test_templates.py b/arkindex/process/tests/test_templates.py
index 0857e6d34a44fd0610ea737378ba87385dd78e85..98cf6a78a31706176375899b952edd489ba44d45 100644
--- a/arkindex/process/tests/test_templates.py
+++ b/arkindex/process/tests/test_templates.py
@@ -271,7 +271,6 @@ class TestTemplates(FixtureAPITestCase):
                     response = self.client.post(
                         reverse("api:create-process-template", kwargs={"pk": str(self.template.id)}),
                         data={"process_id": str(self.process.id)},
-                        format="json",
                     )
                     self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -287,7 +286,6 @@ class TestTemplates(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:create-process-template", kwargs={"pk": str(self.template.id)}),
                 data={"process_id": str(local_process.id)},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -305,7 +303,6 @@ class TestTemplates(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:apply-process-template", kwargs={"pk": str(self.private_template.id)}),
                 data={"process_id": str(self.process.id)},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
@@ -326,7 +323,6 @@ class TestTemplates(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:apply-process-template", kwargs={"pk": str(self.private_template.id)}),
                 data={"process_id": str(self.process.id)},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
@@ -351,7 +347,6 @@ class TestTemplates(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:apply-process-template", kwargs={"pk": str(self.private_template.id)}),
                 data={"process_id": str(self.process.id)},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
@@ -374,7 +369,6 @@ class TestTemplates(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:apply-process-template", kwargs={"pk": str(self.template.id)}),
             data={"process_id": str(process_with_template.id)},
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
@@ -390,7 +384,6 @@ class TestTemplates(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:apply-process-template", kwargs={"pk": str(self.process.id)}),
             data={"process_id": str(self.process.id)},
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
 
@@ -401,7 +394,6 @@ class TestTemplates(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:apply-process-template", kwargs={"pk": str(self.template.id)}),
                 data={"process_id": str(self.process.id)},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.assertEqual(response.json()["template_id"], str(self.template.id))
@@ -433,7 +425,6 @@ class TestTemplates(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:apply-process-template", kwargs={"pk": str(self.template.id)}),
                 data={"process_id": str(self.process.id)},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -480,7 +471,6 @@ class TestTemplates(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:apply-process-template", kwargs={"pk": str(self.template.id)}),
                 data={"process_id": str(process.id)},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.assertEqual(response.json()["template_id"], str(self.template.id))
@@ -556,7 +546,6 @@ class TestTemplates(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:apply-process-template", kwargs={"pk": str(self.template.id)}),
                 data={"process_id": str(self.process.id)},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"non_field_errors": ["This template contains one or more unavailable worker versions and cannot be applied."]})
@@ -571,7 +560,6 @@ class TestTemplates(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:apply-process-template", kwargs={"pk": str(self.template.id)}),
                 data={"process_id": str(self.process.id)},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"non_field_errors": ["This template contains one or more worker versions from archived workers and cannot be applied."]})
@@ -587,7 +575,6 @@ class TestTemplates(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:apply-process-template", kwargs={"pk": str(self.template.id)}),
                 data={"process_id": str(self.process.id)},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -605,7 +592,6 @@ class TestTemplates(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:apply-process-template", kwargs={"pk": str(self.template.id)}),
                 data={"process_id": str(self.process.id)},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -624,7 +610,6 @@ class TestTemplates(FixtureAPITestCase):
                     response = self.client.post(
                         reverse("api:apply-process-template", kwargs={"pk": str(self.template.id)}),
                         data={"process_id": str(self.process.id)},
-                        format="json",
                     )
                     self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -642,7 +627,6 @@ class TestTemplates(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:apply-process-template", kwargs={"pk": str(self.template.id)}),
                 data={"process_id": str(local_process.id)},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -658,7 +642,6 @@ class TestTemplates(FixtureAPITestCase):
             response = self.client.get(
                 reverse("api:process-list"),
                 data={"mode": "template", "with_tasks": True},
-                format="json",
             )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
         # The 'with_tasks' filter should be ignored and some templates should be returned
diff --git a/arkindex/process/tests/test_worker_configurations.py b/arkindex/process/tests/test_worker_configurations.py
index e80b58dc7b29b2c728c2f95d287fa055756c8055..4c16a653a2bd1899073a71cb591776b9ee62b85a 100644
--- a/arkindex/process/tests/test_worker_configurations.py
+++ b/arkindex/process/tests/test_worker_configurations.py
@@ -140,7 +140,6 @@ class TestWorkerConfigurations(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:worker-configurations", kwargs={"pk": str(self.worker_2.id)}),
                 data={"name": name, "configuration": {"key": "value", "cahuete": "bidule"}},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
@@ -158,7 +157,6 @@ class TestWorkerConfigurations(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:worker-configurations", kwargs={"pk": str(self.worker_2.id)}),
                 data={"name": "New configuration", "configuration": config},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
@@ -178,7 +176,6 @@ class TestWorkerConfigurations(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:worker-configurations", kwargs={"pk": str(self.worker_2.id)}),
                 data={"name": "a config name", "configuration": config},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
@@ -201,7 +198,6 @@ class TestWorkerConfigurations(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:worker-configurations", kwargs={"pk": str(self.worker_2.id)}),
                 data={"name": "a config name", "configuration": config_2},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(
@@ -227,7 +223,6 @@ class TestWorkerConfigurations(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:worker-configurations", kwargs={"pk": str(self.worker_2.id)}),
                 data={"name": name, "configuration": config},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         configuration = self.worker_2.configurations.get(name=name)
@@ -248,7 +243,6 @@ class TestWorkerConfigurations(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:worker-configurations", kwargs={"pk": str(self.worker_2.id)}),
                 data={"name": name},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertEqual(response.json(), {"configuration": ["This field is required."]})
@@ -258,7 +252,7 @@ class TestWorkerConfigurations(FixtureAPITestCase):
         with self.assertNumQueries(3):
             response = self.client.post(
                 reverse("api:worker-configurations", kwargs={"pk": str(self.worker_1.id)}),
-                data={"name": "test_config", "configuration": []}, format="json"
+                data={"name": "test_config", "configuration": []},
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -270,7 +264,7 @@ class TestWorkerConfigurations(FixtureAPITestCase):
         with self.assertNumQueries(3):
             response = self.client.post(
                 reverse("api:worker-configurations", kwargs={"pk": str(self.worker_1.id)}),
-                data={"name": "test_config", "configuration": None}, format="json"
+                {"name": "test_config", "configuration": None},
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -282,7 +276,7 @@ class TestWorkerConfigurations(FixtureAPITestCase):
         with self.assertNumQueries(3):
             response = self.client.post(
                 reverse("api:worker-configurations", kwargs={"pk": str(self.worker_1.id)}),
-                data={"name": "test_config", "configuration": {}}, format="json"
+                {"name": "test_config", "configuration": {}},
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -412,7 +406,6 @@ class TestWorkerConfigurations(FixtureAPITestCase):
                     "configuration": {"stop": "hammertime"},
                     "archived": True,
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -438,7 +431,6 @@ class TestWorkerConfigurations(FixtureAPITestCase):
                     "name": "new name",
                     "archived": True,
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -466,7 +458,6 @@ class TestWorkerConfigurations(FixtureAPITestCase):
                     "name": "new name",
                     "archived": False,
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -489,7 +480,6 @@ class TestWorkerConfigurations(FixtureAPITestCase):
                     "name": "new name",
                     "archived": False,
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -576,7 +566,6 @@ class TestWorkerConfigurations(FixtureAPITestCase):
                     "configuration": {"stop": "hammertime"},
                     "archived": True,
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -601,7 +590,6 @@ class TestWorkerConfigurations(FixtureAPITestCase):
                 data={
                     "name": "new name",
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -627,7 +615,6 @@ class TestWorkerConfigurations(FixtureAPITestCase):
                 data={
                     "name": "new name",
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
diff --git a/arkindex/process/tests/test_workerruns.py b/arkindex/process/tests/test_workerruns.py
index a6c4579c038c9a09d781d74d80f97044b7d25e10..40ad68fcdeb66fe6477998646c1e3d51ad717598 100644
--- a/arkindex/process/tests/test_workerruns.py
+++ b/arkindex/process/tests/test_workerruns.py
@@ -183,7 +183,6 @@ class TestWorkerRuns(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:worker-run-list", kwargs={"pk": str(self.process_2.id)}),
                 data={"worker_version_id": str(self.version_1.id), "parents": []},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
@@ -201,7 +200,6 @@ class TestWorkerRuns(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:worker-run-list", kwargs={"pk": str(self.process_2.id)}),
                 data={"worker_version_id": str(self.version_1.id), "parents": []},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -219,7 +217,6 @@ class TestWorkerRuns(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:worker-run-list", kwargs={"pk": str(self.process_2.id)}),
                 data={"worker_version_id": version_id},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -254,7 +251,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                             "model_version_id": str(model_version.id) if model_version else None,
                             "configuration_id": str(configuration.id) if configuration else None,
                         },
-                        format="json",
                     )
                     self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -271,7 +267,6 @@ class TestWorkerRuns(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:worker-run-list", kwargs={"pk": str(self.process_2.id)}),
                 data={"worker_version_id": str(self.version_1.id), "parents": []},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -286,7 +281,6 @@ class TestWorkerRuns(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:worker-run-list", kwargs={"pk": str(self.process_2.id)}),
                 data={"worker_version_id": str(self.version_1.id), "parents": []},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -303,7 +297,6 @@ class TestWorkerRuns(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:worker-run-list", kwargs={"pk": str(self.process_2.id)}),
                 data={"worker_version_id": str(self.version_1.id), "model_version_id": str(self.model_version_1.id)},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -316,7 +309,6 @@ class TestWorkerRuns(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:worker-run-list", kwargs={"pk": uuid.uuid4()}),
                 data={"worker_version_id": str(self.version_1.id), "parents": []},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
 
@@ -334,7 +326,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                     response = self.client.post(
                         reverse("api:worker-run-list", kwargs={"pk": str(self.process_2.id)}),
                         {"worker_version_id": str(self.version_1.id)},
-                        format="json",
                     )
                     self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -349,7 +340,6 @@ class TestWorkerRuns(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:worker-run-list", kwargs={"pk": str(process.id)}),
                 {"worker_version_id": str(self.version_1.id), "parents": []},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
 
@@ -367,7 +357,6 @@ class TestWorkerRuns(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:worker-run-list", kwargs={"pk": str(process.id)}),
                 data={"worker_version_id": str(self.version_1.id), "parents": []},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -389,7 +378,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                     response = self.client.post(
                         reverse("api:worker-run-list", kwargs={"pk": str(self.process_2.id)}),
                         {"worker_version_id": str(self.version_1.id), "parents": []},
-                        format="json",
                     )
                     self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
@@ -465,7 +453,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                     "parents": [],
                     "configuration_id": str(self.configuration_1.id)
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
@@ -526,7 +513,6 @@ class TestWorkerRuns(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:worker-run-list", kwargs={"pk": str(self.process_2.id)}),
                 data={"worker_version_id": str(self.version_1.id), "parents": [], "configuration_id": str(self.configuration_2.id)},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -587,7 +573,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                     response = self.client.post(
                         reverse("api:worker-run-list", kwargs={"pk": str(self.process_2.id)}),
                         data=payload,
-                        format="json",
                     )
                     if response.status_code == 400:
                         self.assertDictEqual(response.json(), {})
@@ -956,7 +941,6 @@ class TestWorkerRuns(FixtureAPITestCase):
             response = self.client.put(
                 reverse("api:worker-run-details", kwargs={"pk": str(self.run_1.id)}),
                 data={},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -977,7 +961,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                 data={
                     "parents": [str(run_2.id)],
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
@@ -1041,7 +1024,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                 data={
                     "parents": [str(run_2.id)],
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
 
@@ -1054,7 +1036,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                 data={
                     "parents": ["12341234-1234-1234-1234-123412341234"],
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -1077,7 +1058,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                         str(run_2.id),
                     ],
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -1111,7 +1091,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                     "process_id": str(self.process_2.id),
                     "parents": [],
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -1173,7 +1152,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                 data={
                     "worker_version_id": str(self.version_2.id),
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -1236,7 +1214,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                     "parents": [],
                     "configuration_id": str(self.configuration_1.id)
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -1302,7 +1279,6 @@ class TestWorkerRuns(FixtureAPITestCase):
             response = self.client.put(
                 reverse("api:worker-run-details", kwargs={"pk": self.run_1.id}),
                 data={"parents": [], "configuration_id": str(self.configuration_2.id)},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -1322,7 +1298,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                 data={
                     "parents": [],
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -1353,7 +1328,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                     "model_version_id": str(self.model_version_1.id),
                     "parents": []
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -1385,7 +1359,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                     "model_version_id": random_model_version_uuid,
                     "parents": []
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -1427,7 +1400,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                     "model_version_id": str(model_version_no_access.id),
                     "parents": []
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -1498,7 +1470,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                             "model_version_id": str(model_version.id),
                             "parents": [],
                         },
-                        format="json",
                     )
                     self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -1533,7 +1504,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                     "model_version_id": str(self.model_version_1.id),
                     "parents": []
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -1559,7 +1529,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                 data={
                     "model_version_id": str(self.model_version_1.id),
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -1603,7 +1572,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                             "model_version_id": str(model_version.id),
                             "parents": [],
                         },
-                        format="json",
                     )
                     self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -1692,7 +1660,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                     "configuration_id": str(self.configuration_1.id),
                     "parents": []
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -1777,7 +1744,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                 data={
                     "parents": [str(run_2.id)],
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -1863,7 +1829,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                             "model_version_id": str(model_version.id) if model_version else None,
                             "configuration_id": str(configuration.id) if configuration else None,
                         },
-                        format="json",
                     )
                     self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -1905,7 +1870,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                 data={
                     "parents": [str(run_2.id)],
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
@@ -1946,7 +1910,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                 data={
                     "parents": [str(run_2.id)],
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
 
@@ -1978,7 +1941,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                 data={
                     "parents": ["12341234-1234-1234-1234-123412341234"],
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -2000,7 +1962,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                 data={
                     "process_id": str(self.process_2.id),
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -2062,7 +2023,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                 data={
                     "worker_version_id": str(self.version_2.id),
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -2123,7 +2083,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                 data={
                     "configuration_id": str(self.configuration_1.id)
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -2187,7 +2146,6 @@ class TestWorkerRuns(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:worker-run-details", kwargs={"pk": self.run_1.id}),
                 data={"configuration_id": str(self.configuration_2.id)},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -2207,7 +2165,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                 data={
                     "parents": [],
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -2237,7 +2194,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                 data={
                     "model_version_id": str(self.model_version_1.id),
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -2268,7 +2224,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                 data={
                     "model_version_id": random_model_version_uuid,
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -2303,7 +2258,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                 data={
                     "model_version_id": str(model_version_no_access.id),
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -2373,7 +2327,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                         data={
                             "model_version_id": str(model_version.id),
                         },
-                        format="json",
                     )
                     self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -2408,7 +2361,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                     "model_version_id": str(self.model_version_1.id),
                     "parents": []
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -2434,7 +2386,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                 data={
                     "model_version_id": str(self.model_version_1.id),
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -2476,7 +2427,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                         data={
                             "model_version_id": str(model_version.id),
                         },
-                        format="json",
                     )
                     self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -2562,7 +2512,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                 data={
                     "model_version_id": str(self.model_version_1.id),
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -2646,7 +2595,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                 data={
                     "parents": [str(run_2.id)],
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -2732,7 +2680,6 @@ class TestWorkerRuns(FixtureAPITestCase):
                             "model_version_id": str(model_version.id) if model_version else None,
                             "configuration_id": str(configuration.id) if configuration else None,
                         },
-                        format="json",
                     )
                     self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
diff --git a/arkindex/process/tests/test_workerruns_use_gpu.py b/arkindex/process/tests/test_workerruns_use_gpu.py
index ef1bcb1aea32486c8cf48918cda3aa187f8bfb41..79704d3cf80653b5210d34b9c889286eb76a8c54 100644
--- a/arkindex/process/tests/test_workerruns_use_gpu.py
+++ b/arkindex/process/tests/test_workerruns_use_gpu.py
@@ -63,7 +63,6 @@ class TestWorkerRunsGPU(FixtureAPITestCase):
                     response = self.client.post(
                         reverse("api:worker-run-list", kwargs={"pk": str(self.test_process.id)}),
                         {"worker_version_id": str(worker_version.id), "parents": []},
-                        format="json",
                     )
                     self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
@@ -119,7 +118,6 @@ class TestWorkerRunsGPU(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:worker-run-list", kwargs={"pk": str(self.test_process.id)}),
                 {"worker_version_id": str(self.version_gpu_required.id), "parents": [], "use_gpu": False},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
diff --git a/arkindex/process/tests/test_workers.py b/arkindex/process/tests/test_workers.py
index 923724c89751ad8c18edf03369d699ad45feca7a..17406155d9a1714890b1d0c822e4f6eb9da03642 100644
--- a/arkindex/process/tests/test_workers.py
+++ b/arkindex/process/tests/test_workers.py
@@ -1192,7 +1192,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:worker-versions", kwargs={"pk": "12341234-1234-1234-1234-123412341234"}),
                 data={"configuration": {"test": "test2"}},
-                format="json",
                 HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
             )
             self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
@@ -1208,7 +1207,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                     "state": "available",
                 },
                 HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -1228,7 +1226,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                     "state": "available",
                 },
                 HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -1259,7 +1256,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                     "configuration": {},
                     "revision_url": "https://gitlab.com/NERV/eva/commit/eva-01"
                 },
-                format="json",
                 HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -1277,7 +1273,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:worker-versions", kwargs={"pk": str(self.worker_reco.id)}),
                 data={"configuration": {"test": "test2"}, "model_usage": FeatureUsage.Required.value},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -1293,7 +1288,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:worker-versions", kwargs={"pk": str(self.worker_custom.id)}),
                 data={"configuration": {"test": "test2"}, "model_usage": FeatureUsage.Required.value},
-                format="json",
                 HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -1310,7 +1304,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:worker-versions", kwargs={"pk": str(self.worker_custom.id)}),
                 data={"configuration": {"test": "val"}, "model_usage": FeatureUsage.Required.value},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
@@ -1328,7 +1321,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:worker-versions", kwargs={"pk": str(self.worker_dla.id)}),
                 data={"revision_url": "https://gitlab.com/NERV/eva/commit/eva-01", "configuration": {"test": "test2"}, "model_usage": FeatureUsage.Required.value},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
@@ -1367,7 +1359,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:worker-versions", kwargs={"pk": str(self.worker_custom.id)}),
                 data={"configuration": {"test": "val"}, "model_usage": FeatureUsage.Required.value},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         data = response.json()
@@ -1403,7 +1394,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:worker-versions", kwargs={"pk": str(self.worker_reco.id)}),
                 data={"configuration": "test"},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertEqual(response.json(), {"configuration": ['Expected a dictionary of items but got type "str".']})
@@ -1416,7 +1406,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 "model_usage": FeatureUsage.Required.value,
                 "revision_url": "https://gitlab.com/NERV/eva/commit/eva-01",
             },
-            format="json",
             HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
         )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -1440,7 +1429,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 "configuration": {"test": "test2"},
                 "revision_url": "https://gitlab.com/NERV/eva/commit/eva-01",
             },
-            format="json",
             HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -1456,7 +1444,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                     "revision_url": "https://gitlab.com/NERV/eva/commit/eva-01",
                     "tag": "eva-01",
                 },
-                format="json",
                 HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -1479,7 +1466,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:worker-versions", kwargs={"pk": str(self.worker_reco.id)}),
                 data={"configuration": {"test": "test2"}, "revision_url": "https://gitlab.com/NERV/eva/commit/eva-01", "tag": "eva-01"},
-                format="json",
                 HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -1490,7 +1476,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:worker-versions", kwargs={"pk": str(self.worker_reco.id)}),
                 data={"configuration": {"test": "test2"}, "revision_url": "https://gitlab.com/NERV/eva/commit/eva-01", "tag": ""},
-                format="json",
                 HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -1500,7 +1485,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:worker-versions", kwargs={"pk": str(self.worker_reco.id)}),
             data={"configuration": {"test": "test2"}, "revision_url": "https://gitlab.com/NERV/eva/commit/eva-01", "gpu_usage": "not_supported"},
-            format="json",
             HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -1513,7 +1497,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 "revision_url": "https://gitlab.com/NERV/eva/commit/eva-01",
                 "gpu_usage": "disabled",
             },
-            format="json",
             HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
         )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -1531,7 +1514,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 "gpu_usage": "disabled",
                 "revision_url": "https://gitlab.com/NERV/eva/commit/eva-01",
             },
-            format="json",
             HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
         )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -1564,7 +1546,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 "revision_url": "https://gitlab.com/NERV/eva/commit/eva-01",
                 "gpu_usage": "disabled",
             },
-            format="json",
             HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
         )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -1590,7 +1571,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 },
                 "gpu_usage": "disabled",
             },
-            format="json",
             HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -1607,7 +1587,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 "revision_url": "https://gitlab.com/NERV/eva/commit/eva-01",
                 "gpu_usage": "disabled",
             },
-            format="json",
             HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
         )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -1636,7 +1615,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 "revision_url": "https://gitlab.com/NERV/eva/commit/eva-01",
                 "gpu_usage": "disabled",
             },
-            format="json",
             HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
         )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -1672,7 +1650,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 "revision_url": "https://gitlab.com/NERV/eva/commit/eva-01",
                 "gpu_usage": "disabled",
             },
-            format="json",
             HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
         )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
@@ -1702,7 +1679,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 },
                 "gpu_usage": "disabled",
             },
-            format="json",
             HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -1727,7 +1703,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 },
                 "gpu_usage": "disabled",
             },
-            format="json",
             HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -1752,7 +1727,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 },
                 "gpu_usage": "disabled",
             },
-            format="json",
             HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -1777,7 +1751,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 },
                 "gpu_usage": "disabled",
             },
-            format="json",
             HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -1802,7 +1775,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 },
                 "gpu_usage": "disabled",
             },
-            format="json",
             HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -1825,7 +1797,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 },
                 "gpu_usage": "disabled",
             },
-            format="json",
             HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -1842,7 +1813,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 },
                 "gpu_usage": "disabled",
             },
-            format="json",
             HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -1868,7 +1838,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 },
                 "gpu_usage": "disabled",
             },
-            format="json",
             HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -1899,7 +1868,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 },
                 "gpu_usage": "disabled",
             },
-            format="json",
             HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -1929,7 +1897,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 },
                 "gpu_usage": "disabled",
             },
-            format="json",
             HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -1954,7 +1921,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 },
                 "gpu_usage": "disabled",
             },
-            format="json",
             HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -1988,7 +1954,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 },
                 "gpu_usage": "disabled",
             },
-            format="json",
             HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -2028,7 +1993,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                             }
                         },
                     },
-                    format="json",
                     HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
                 )
                 self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -2044,7 +2008,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                     }
                 },
             },
-            format="json",
             HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -2126,7 +2089,7 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 "state": "error",
                 "gpu_usage": "disabled",
                 "model_usage": FeatureUsage.Disabled.value,
-            }, format="json"
+            },
         )
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertEqual(response.json(), {"detail": "Authentication credentials were not provided."})
@@ -2141,7 +2104,7 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 "state": "error",
                 "gpu_usage": "disabled",
                 "model_usage": FeatureUsage.Disabled.value,
-            }, format="json"
+            },
         )
         self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
 
@@ -2162,7 +2125,7 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 "state": "error",
                 "gpu_usage": "disabled",
                 "model_usage": FeatureUsage.Disabled.value,
-            }, format="json"
+            },
         )
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertEqual(response.json(), {"detail": "Only Ponos tasks are allowed to update a worker version."})
@@ -2182,7 +2145,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 "state": "error",
                 "tag": "eva-01"
             },
-            format="json",
             HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
@@ -2209,7 +2171,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 data={
                     "tag": "eva-01"
                 },
-                format="json",
                 HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -2222,7 +2183,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 data={
                     "tag": ""
                 },
-                format="json",
                 HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -2239,7 +2199,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 data={
                     "revision_url": "updated"
                 },
-                format="json",
                 HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
@@ -2256,7 +2215,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
                 data={
                     "revision_url": "https://gitlab.com/NERV/eva/commit/eva-01"
                 },
-                format="json",
                 HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
             )
             # revision_url just gets ignored
@@ -2274,7 +2232,6 @@ class TestWorkersWorkerVersions(FixtureAPITestCase):
         response = self.client.patch(
             reverse("api:version-retrieve", kwargs={"pk": str(self.version_1.id)}),
             data={"state": "available"},
-            format="json",
             HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
diff --git a/arkindex/project/settings.py b/arkindex/project/settings.py
index 90b3339d2fb6ce35e5349e88f4f3a5a2ef429ac4..ecb16e5f48ea216a27d5cfd2ec12d3742e102b19 100644
--- a/arkindex/project/settings.py
+++ b/arkindex/project/settings.py
@@ -209,6 +209,7 @@ REST_FRAMEWORK = {
     "DEFAULT_PAGINATION_CLASS": "arkindex.project.pagination.PageNumberPagination",
     "DEFAULT_SCHEMA_CLASS": "arkindex.project.openapi.AutoSchema",
     "PAGE_SIZE": 20,
+    "TEST_REQUEST_DEFAULT_FORMAT": "json",
 }
 
 SIMPLE_JWT = {
diff --git a/arkindex/training/tests/test_dataset_sets_api.py b/arkindex/training/tests/test_dataset_sets_api.py
index cafedafb83aba56654d34b3a7e5d6b835d8aec2b..74a756dd96bf32ea03eab12c60bd865362491a33 100644
--- a/arkindex/training/tests/test_dataset_sets_api.py
+++ b/arkindex/training/tests/test_dataset_sets_api.py
@@ -40,7 +40,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:dataset-sets", kwargs={"pk": self.dataset.pk}),
                 data={"name": "Unit-00"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(response.json(), {"detail": "Authentication credentials were not provided."})
@@ -52,7 +51,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:dataset-sets", kwargs={"pk": self.dataset.pk}),
                 data={"name": "Unit-00"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(response.json(), {"detail": "You do not have permission to perform this action."})
@@ -63,7 +61,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:dataset-sets", kwargs={"pk": "aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa"}),
                 data={"name": "Unit-00"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
         self.assertDictEqual(response.json(), {"detail": "No Dataset matches the given query."})
@@ -76,7 +73,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:dataset-sets", kwargs={"pk": str(self.private_dataset.pk)}),
                 data={"name": "Unit-00"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
         self.assertDictEqual(response.json(), {"detail": "No Dataset matches the given query."})
@@ -93,7 +89,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:dataset-sets", kwargs={"pk": self.private_dataset.pk}),
                 data={"name": "Unit-00"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
@@ -114,7 +109,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
                     response = self.client.post(
                         reverse("api:dataset-sets", kwargs={"pk": self.dataset.pk}),
                         data={"name": "Unit-00"},
-                        format="json"
                     )
                     self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -127,7 +121,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:dataset-sets", kwargs={"pk": self.dataset.pk}),
                 data={"name": "train"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -140,7 +133,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:dataset-sets", kwargs={"pk": self.dataset.pk}),
                 data={"name": "Unit-00"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
@@ -157,7 +149,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
             response = self.client.put(
                 reverse("api:dataset-set", kwargs={"dataset": self.dataset.pk, "set": self.train_set.pk}),
                 data={"name": "Unit-00"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(response.json(), {"detail": "Authentication credentials were not provided."})
@@ -169,7 +160,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
             response = self.client.put(
                 reverse("api:dataset-set", kwargs={"dataset": self.dataset.pk, "set": self.train_set.pk}),
                 data={"name": "Unit-00"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(response.json(), {"detail": "You do not have permission to perform this action."})
@@ -180,7 +170,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
             response = self.client.put(
                 reverse("api:dataset-set", kwargs={"dataset": "aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa", "set": self.train_set.pk}),
                 data={"name": "Unit-00"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
         self.assertDictEqual(response.json(), {"detail": "No Dataset matches the given query."})
@@ -191,7 +180,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
             response = self.client.put(
                 reverse("api:dataset-set", kwargs={"dataset": self.dataset.id, "set": "aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa"}),
                 data={"name": "Unit-00"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
         self.assertDictEqual(response.json(), {"detail": "No DatasetSet matches the given query."})
@@ -204,7 +192,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
             response = self.client.put(
                 reverse("api:dataset-set", kwargs={"dataset": self.dataset.pk, "set": self.train_set.pk}),
                 data={"name": "Unit-00"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
         self.assertDictEqual(response.json(), {"detail": "No Dataset matches the given query."})
@@ -221,7 +208,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
             response = self.client.put(
                 reverse("api:dataset-set", kwargs={"dataset": self.dataset.pk, "set": self.train_set.pk}),
                 data={"name": "Unit-00"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
@@ -242,7 +228,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
                     response = self.client.put(
                         reverse("api:dataset-set", kwargs={"dataset": self.dataset.pk, "set": self.train_set.pk}),
                         data={"name": "Unit-00"},
-                        format="json"
                     )
                     self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -255,7 +240,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
             response = self.client.put(
                 reverse("api:dataset-set", kwargs={"dataset": self.dataset.pk, "set": self.train_set.pk}),
                 data={"name": "dev"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -268,7 +252,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
             response = self.client.put(
                 reverse("api:dataset-set", kwargs={"dataset": self.dataset.pk, "set": self.train_set.pk}),
                 data={"name": "Unit-00"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -286,7 +269,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:dataset-set", kwargs={"dataset": self.dataset.pk, "set": self.train_set.pk}),
                 data={"name": "Unit-00"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(response.json(), {"detail": "Authentication credentials were not provided."})
@@ -298,7 +280,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:dataset-set", kwargs={"dataset": self.dataset.pk, "set": self.train_set.pk}),
                 data={"name": "Unit-00"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(response.json(), {"detail": "You do not have permission to perform this action."})
@@ -309,7 +290,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:dataset-set", kwargs={"dataset": "aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa", "set": self.train_set.pk}),
                 data={"name": "Unit-00"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
         self.assertDictEqual(response.json(), {"detail": "No Dataset matches the given query."})
@@ -320,7 +300,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:dataset-set", kwargs={"dataset": self.dataset.id, "set": "aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa"}),
                 data={"name": "Unit-00"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
         self.assertDictEqual(response.json(), {"detail": "No DatasetSet matches the given query."})
@@ -333,7 +312,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:dataset-set", kwargs={"dataset": self.dataset.pk, "set": self.train_set.pk}),
                 data={"name": "Unit-00"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
         self.assertDictEqual(response.json(), {"detail": "No Dataset matches the given query."})
@@ -350,7 +328,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:dataset-set", kwargs={"dataset": self.dataset.pk, "set": self.train_set.pk}),
                 data={"name": "Unit-00"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
@@ -371,7 +348,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
                     response = self.client.patch(
                         reverse("api:dataset-set", kwargs={"dataset": self.dataset.pk, "set": self.train_set.pk}),
                         data={"name": "Unit-00"},
-                        format="json"
                     )
                     self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -384,7 +360,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:dataset-set", kwargs={"dataset": self.dataset.pk, "set": self.train_set.pk}),
                 data={"name": "dev"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -397,7 +372,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:dataset-set", kwargs={"dataset": self.dataset.pk, "set": self.train_set.pk}),
                 data={"name": "Unit-00"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -414,7 +388,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
         with self.assertNumQueries(0):
             response = self.client.delete(
                 reverse("api:dataset-set", kwargs={"dataset": self.dataset.pk, "set": self.train_set.pk}),
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(response.json(), {"detail": "Authentication credentials were not provided."})
@@ -425,7 +398,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
         with self.assertNumQueries(2):
             response = self.client.delete(
                 reverse("api:dataset-set", kwargs={"dataset": self.dataset.pk, "set": self.train_set.pk}),
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(response.json(), {"detail": "You do not have permission to perform this action."})
@@ -435,7 +407,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
         with self.assertNumQueries(3):
             response = self.client.delete(
                 reverse("api:dataset-set", kwargs={"dataset": "aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa", "set": self.train_set.pk}),
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
         self.assertDictEqual(response.json(), {"detail": "No Dataset matches the given query."})
@@ -445,7 +416,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
         with self.assertNumQueries(6):
             response = self.client.delete(
                 reverse("api:dataset-set", kwargs={"dataset": self.dataset.id, "set": "aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa"}),
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
         self.assertDictEqual(response.json(), {"detail": "No DatasetSet matches the given query."})
@@ -457,7 +427,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
         with self.assertNumQueries(3):
             response = self.client.delete(
                 reverse("api:dataset-set", kwargs={"dataset": self.dataset.pk, "set": self.train_set.pk}),
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
         self.assertDictEqual(response.json(), {"detail": "No Dataset matches the given query."})
@@ -476,7 +445,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
                 with self.assertNumQueries(5):
                     response = self.client.delete(
                         reverse("api:dataset-set", kwargs={"dataset": self.dataset.pk, "set": self.train_set.pk}),
-                        format="json"
                     )
                     self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
@@ -496,7 +464,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
                 with self.assertNumQueries(5):
                     response = self.client.delete(
                         reverse("api:dataset-set", kwargs={"dataset": self.dataset.pk, "set": self.train_set.pk}),
-                        format="json"
                     )
                     self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -508,7 +475,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
         with self.assertNumQueries(7):
             response = self.client.delete(
                 reverse("api:dataset-set", kwargs={"dataset": self.dataset.pk, "set": self.train_set.pk}),
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertEqual(response.json(), ["This dataset set is selected in a process and cannot be deleted."])
@@ -524,7 +490,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
         with self.assertNumQueries(7):
             response = self.client.delete(
                 reverse("api:dataset-set", kwargs={"dataset": test_dataset.pk, "set": test_set.pk}),
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertEqual(response.json(), ["This dataset set is the only one in its dataset and cannot be deleted."])
@@ -539,7 +504,6 @@ class TestDatasetSetsAPI(FixtureAPITestCase):
         with self.assertNumQueries(9):
             response = self.client.delete(
                 reverse("api:dataset-set", kwargs={"dataset": self.dataset.pk, "set": self.train_set.pk}),
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_204_NO_CONTENT)
 
diff --git a/arkindex/training/tests/test_datasets_api.py b/arkindex/training/tests/test_datasets_api.py
index 366166fa9bc1dde4524a017902844ab24ea47cdb..705e1d3a04ef85f434318a614c71a5db14850209 100644
--- a/arkindex/training/tests/test_datasets_api.py
+++ b/arkindex/training/tests/test_datasets_api.py
@@ -133,7 +133,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:corpus-datasets", kwargs={"pk": self.corpus.pk}),
                 data={"name": "My dataset", "description": "My dataset for my experiments."},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(response.json(), {"detail": "Authentication credentials were not provided."})
@@ -145,7 +144,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:corpus-datasets", kwargs={"pk": self.corpus.pk}),
                 data={"name": "My dataset", "description": "My dataset for my experiments."},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(response.json(), {"detail": "You do not have permission to perform this action."})
@@ -156,7 +154,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:corpus-datasets", kwargs={"pk": "aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa"}),
                 data={"name": "My dataset", "description": "My dataset for my experiments."},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
         self.assertDictEqual(response.json(), {"detail": "No Corpus matches the given query."})
@@ -168,7 +165,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:corpus-datasets", kwargs={"pk": self.private_corpus.pk}),
                 data={"name": "My dataset", "description": "My dataset for my experiments."},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
@@ -183,7 +179,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:corpus-datasets", kwargs={"pk": self.corpus.pk}),
                 data={"description": "My dataset for my experiments."},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"name": ["This field is required."]})
@@ -194,7 +189,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:corpus-datasets", kwargs={"pk": self.corpus.pk}),
                 data={"name": "", "description": "My dataset for my experiments."},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"name": ["This field may not be blank."]})
@@ -205,7 +199,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:corpus-datasets", kwargs={"pk": self.corpus.pk}),
                 data={"name": "        ", "description": "My dataset for my experiments."},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"name": ["This field may not be blank."]})
@@ -219,7 +212,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                     "name": "In elementum leo et lectus finibus, eget lobortis ligula posuere. Vivamus finibus quis sapien in mattis. Cras in libero.",
                     "description": "My dataset for my experiments."
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"name": ["Ensure this field has no more than 100 characters."]})
@@ -233,7 +225,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                     "name": "First Dataset",
                     "description": "My dataset for my experiments."
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"non_field_errors": ["A dataset with this name already exists in this corpus."]})
@@ -244,7 +235,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:corpus-datasets", kwargs={"pk": self.corpus.pk}),
                 data={"name": "My dataset"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"description": ["This field is required."]})
@@ -255,7 +245,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:corpus-datasets", kwargs={"pk": self.corpus.pk}),
                 data={"name": "My dataset", "description": ""},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"description": ["This field may not be blank."]})
@@ -266,7 +255,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:corpus-datasets", kwargs={"pk": self.corpus.pk}),
                 data={"name": "My dataset", "description": "             "},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"description": ["This field may not be blank."]})
@@ -277,7 +265,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:corpus-datasets", kwargs={"pk": self.corpus.pk}),
                 data={"name": "My dataset", "description": "My dataset for my experiments.", "unique_elements": False},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         created_dataset = Dataset.objects.get(name="My dataset")
@@ -312,7 +299,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:corpus-datasets", kwargs={"pk": self.corpus.pk}),
                 data={"name": "My dataset", "description": "My dataset for my experiments.", "state": "complete"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         created_dataset = Dataset.objects.get(name="My dataset")
@@ -348,7 +334,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:corpus-datasets", kwargs={"pk": self.corpus.pk}),
                 data={"name": "My dataset", "description": "My dataset for my experiments.", "set_names": ["a", "b", "c", "d"]},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         created_dataset = Dataset.objects.get(name="My dataset")
@@ -379,7 +364,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:corpus-datasets", kwargs={"pk": self.corpus.pk}),
                 data={"name": "My dataset", "description": "My dataset for my experiments.", "set_names": []},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"set_names": ["Either do not specify set names to use the default values, or specify a non-empty list of names."]})
@@ -390,7 +374,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:corpus-datasets", kwargs={"pk": self.corpus.pk}),
                 data={"name": "My dataset", "description": "My dataset for my experiments.", "set_names": ["a", "a", "b"]},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"set_names": ["Set names must be unique."]})
@@ -401,7 +384,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:corpus-datasets", kwargs={"pk": self.corpus.pk}),
                 data={"name": "My dataset", "description": "My dataset for my experiments.", "set_names": ["     ", " ", "b"]},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -422,7 +404,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                     "description": "My dataset for my experiments.",
                     "set_names": ["unit-00", "Etiam accumsan ullamcorper mauris eget mattis. Ut porttitor."]
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -441,7 +422,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                     "name": "Shin Seiki Evangelion",
                     "description": "Omedeto!",
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(response.json(), {"detail": "Authentication credentials were not provided."})
@@ -456,7 +436,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                     "name": "Shin Seiki Evangelion",
                     "description": "Omedeto!",
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(response.json(), {"detail": "You do not have permission to perform this action."})
@@ -471,7 +450,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                     "name": "Shin Seiki Evangelion",
                     "description": "Omedeto!",
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(response.json(), {"detail": "You do not have contributor access to corpus Unit Tests."})
@@ -488,7 +466,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                     "name": "Shin Seiki Evangelion",
                     "description": "Omedeto!",
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_404_NOT_FOUND)
         self.assertDictEqual(response.json(), {"detail": "No Dataset matches the given query."})
@@ -502,7 +479,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                     "name": "In elementum leo et lectus finibus, eget lobortis ligula posuere. Vivamus finibus quis sapien in mattis. Cras in libero.",
                     "description": "My dataset for my experiments.",
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"name": ["Ensure this field has no more than 100 characters."]})
@@ -517,7 +493,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                     "name": "Another Dataset",
                     "description": "My dataset for my experiments.",
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"non_field_errors": ["A dataset with this name already exists in this corpus."]})
@@ -528,7 +503,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.put(
                 reverse("api:dataset-update", kwargs={"pk": self.dataset.pk}),
                 data={"name": "Shin Seiki Evangelion"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"description": ["This field is required."]})
@@ -544,7 +518,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                     "description": "Omedeto!",
                     "set_names": ["unit-01", "unit-02"],
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"set_names": ["This API endpoint does not allow updating a dataset's sets."]})
@@ -558,7 +531,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                     "name": "",
                     "description": "          ",
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -576,7 +548,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                     "description": "          ",
                     "set_names": ["unit-00", "unit-00", "unit-02"]
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -591,7 +562,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.put(
                 reverse("api:dataset-update", kwargs={"pk": self.dataset.pk}),
                 data={"name": "a", "description": "a", "unique_elements": False},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.dataset.refresh_from_db()
@@ -610,7 +580,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.put(
                 reverse("api:dataset-update", kwargs={"pk": self.dataset.pk}),
                 data={"name": "a", "description": "a", "unique_elements": True},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -630,7 +599,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                     "description": "Omedeto!",
                     "state": "open"
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.dataset.refresh_from_db()
@@ -652,7 +620,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                     "description": "Omedeto!",
                     "state": "complete"
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.dataset.refresh_from_db()
@@ -693,7 +660,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                         "description": self.dataset.description,
                         "state": state_to.value,
                     },
-                    format="json",
                 )
                 if expected:
                     self.assertEqual(response.status_code, status.HTTP_200_OK)
@@ -723,7 +689,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                         "description": self.dataset.description,
                         "state": state_to.value,
                     },
-                    format="json",
                 )
                 if expected:
                     self.assertEqual(response.status_code, status.HTTP_200_OK)
@@ -748,7 +713,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                     "description": "BB",
                     "unique_elements": False,
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.dataset.refresh_from_db()
@@ -767,7 +731,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                     "description": "Omedeto!",
                     "state": "building"
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -784,7 +747,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                     "description": "Omedeto!",
                     "state": "decommissioned"
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"state": ["Value is not of type DatasetState"]})
@@ -798,7 +760,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:dataset-update", kwargs={"pk": self.dataset.pk}),
                 data={"name": "Shin Seiki Evangelion"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(response.json(), {"detail": "Authentication credentials were not provided."})
@@ -810,7 +771,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:dataset-update", kwargs={"pk": self.dataset.pk}),
                 data={"name": "Shin Seiki Evangelion"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(response.json(), {"detail": "You do not have permission to perform this action."})
@@ -822,7 +782,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:dataset-update", kwargs={"pk": self.dataset.pk}),
                 data={"name": "Shin Seiki Evangelion"},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(response.json(), {"detail": "You do not have contributor access to corpus Unit Tests."})
@@ -838,7 +797,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                 data={
                     "name": "In elementum leo et lectus finibus, eget lobortis ligula posuere. Vivamus finibus quis sapien in mattis. Cras in libero.",
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"name": ["Ensure this field has no more than 100 characters."]})
@@ -852,7 +810,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                 data={
                     "name": "Another Dataset",
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"non_field_errors": ["A dataset with this name already exists in this corpus."]})
@@ -863,7 +820,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:dataset-update", kwargs={"pk": self.dataset.pk}),
                 data={"description": "Omedeto!", "unique_elements": False},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.dataset.refresh_from_db()
@@ -882,7 +838,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                     "name": "                  ",
                     "description": "",
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"name": ["This field may not be blank."], "description": ["This field may not be blank."]})
@@ -898,7 +853,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:dataset-update", kwargs={"pk": self.dataset.pk}),
                 data={"name": "a", "description": "a", "unique_elements": True},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -914,7 +868,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:dataset-update", kwargs={"pk": self.dataset.pk}),
                 data={"state": "open"},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.dataset.refresh_from_db()
@@ -931,7 +884,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                 reverse("api:dataset-update", kwargs={"pk": self.dataset.pk}),
                 HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
                 data={"state": "complete"},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.dataset.refresh_from_db()
@@ -946,7 +898,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                 reverse("api:dataset-update", kwargs={"pk": self.dataset.pk}),
                 HTTP_AUTHORIZATION=f"Ponos {self.task.token}",
                 data={"state": "building"},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -961,7 +912,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                 data={
                     "state": "decommissioned"
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"state": ["Value is not of type DatasetState"]})
@@ -1001,7 +951,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                         "description": self.dataset.description,
                         "state": state_to.value,
                     },
-                    format="json",
                 )
                 if expected:
                     self.assertEqual(response.status_code, status.HTTP_200_OK)
@@ -1027,7 +976,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                 response = self.client.patch(
                     reverse("api:dataset-update", kwargs={"pk": self.dataset.pk}),
                     data={"state": state_to.value},
-                    format="json",
                 )
                 if expected:
                     self.assertEqual(response.status_code, status.HTTP_200_OK)
@@ -1052,7 +1000,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                     "description": "BB",
                     "unique_elements": False,
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.dataset.refresh_from_db()
@@ -1578,7 +1525,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:dataset-elements", kwargs={"pk": self.dataset.id}),
                 data={"set": "test", "element_id": str(element.id)},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -1591,7 +1537,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:dataset-elements", kwargs={"pk": self.dataset.id}),
                 data={"set": "aaaaaaaaaaa", "element_id": str(self.vol.id)},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -1606,7 +1551,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:dataset-elements", kwargs={"pk": self.dataset.id}),
                 data={"set": "test", "element_id": str(self.vol.id)},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertListEqual(response.json(), ["You can only add elements to a dataset in an open state."])
@@ -1621,7 +1565,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:dataset-elements", kwargs={"pk": self.dataset.id}),
                 data={"set": "test", "element_id": str(self.page1.id)},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"non_field_errors": ["This element is already part of this set."]})
@@ -1633,7 +1576,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:dataset-elements", kwargs={"pk": self.dataset.id}),
                 data={"set": "train", "element_id": str(self.page1.id)},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         self.assertQuerySetEqual(
@@ -1649,7 +1591,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:dataset-elements", kwargs={"pk": self.dataset.id}),
                 data={"set": "test", "element_id": str(self.page1.id)},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -1666,7 +1607,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:dataset-elements", kwargs={"pk": self.dataset.id}),
                 data={"set": "test", "element_id": str(self.page1.id)},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         self.assertQuerySetEqual(
@@ -1751,7 +1691,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:dataset-elements-selection", kwargs={"pk": self.corpus.id}),
                 data={"set_id": "AAA"},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -1765,7 +1704,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:dataset-elements-selection", kwargs={"pk": self.corpus.id}),
                 data={"set_id": self.private_dataset_set.id},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -1782,7 +1720,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:dataset-elements-selection", kwargs={"pk": self.corpus.id}),
                 data={"set_id": test_set.id},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -1803,7 +1740,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:dataset-elements-selection", kwargs={"pk": self.corpus.id}),
                 data={"set_id": str(train_set.id)},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_204_NO_CONTENT)
         self.assertQuerySetEqual(
@@ -1825,7 +1761,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:dataset-elements-selection", kwargs={"pk": self.corpus.id}),
                 data={"set_id": str(test_set.id)},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -1845,7 +1780,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:dataset-elements-selection", kwargs={"pk": self.corpus.id}),
                 data={"set_id": str(test_set.id)},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_204_NO_CONTENT)
         self.assertQuerySetEqual(
@@ -2292,7 +2226,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
         with self.assertNumQueries(14):
             response = self.client.post(
                 reverse("api:dataset-clone", kwargs={"pk": self.dataset.id}),
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         self.assertCountEqual(self.corpus.datasets.values_list("name", flat=True), [
@@ -2351,7 +2284,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
         with self.assertNumQueries(13):
             response = self.client.post(
                 reverse("api:dataset-clone", kwargs={"pk": self.dataset.id}),
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         self.assertCountEqual(self.corpus.datasets.values_list("name", flat=True), [
@@ -2402,7 +2334,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
         with self.assertNumQueries(12):
             response = self.client.post(
                 reverse("api:dataset-clone", kwargs={"pk": dataset.id}),
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         data = response.json()
@@ -2610,7 +2541,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                     "count": "d",
                     "sets": "e",
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -2633,7 +2563,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                     "types": ["page", "A", "AAAAAA"],
                     "sets": {"test": .8, "A": .15, "AAAAA": .05},
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -2648,7 +2577,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:dataset-populate", kwargs={"pk": self.dataset.pk}),
                 data={"recursive": True},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -2661,7 +2589,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:dataset-populate", kwargs={"pk": self.dataset.pk}),
                 data={"recursive": True, "sets": {"test": 0.13, "train": 0.37}},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -2674,7 +2601,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:dataset-populate", kwargs={"pk": self.dataset.pk}),
                 data={"recursive": True, "count": 5, "sets": {"test": 0.01, "train": 0.99}},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -2692,7 +2618,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:dataset-populate", kwargs={"pk": self.dataset.pk}),
                 data={"recursive": True, "count": 1, "sets": {"test": 1}},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -2713,7 +2638,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                     "types": ["page", "word"],
                     "count": 11,
                     "sets": {"train": .2, "dev": .7, "test": .1}},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         self.assertEqual(response.json(), {})
@@ -2741,7 +2665,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                     "count": 3,
                     "sets": {"train": 1}
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         self.assertEqual(response.json(), {})
@@ -2771,7 +2694,6 @@ class TestDatasetsAPI(FixtureAPITestCase):
                     "count": 12,
                     "sets": {"train": 1}
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         self.assertQuerysetEqual(
diff --git a/arkindex/training/tests/test_metrics_api.py b/arkindex/training/tests/test_metrics_api.py
index a1efc6de3c6b6ceeb0f515a73d59536f4f73ad53..8c52cb0e85c2ef5aaf6714033333102eee81ad14 100644
--- a/arkindex/training/tests/test_metrics_api.py
+++ b/arkindex/training/tests/test_metrics_api.py
@@ -37,7 +37,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                     "name": "a test metric",
                     "value": 1.2
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(response.json(), {"detail": "Authentication credentials were not provided."})
@@ -53,7 +52,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                     "name": "a test metric",
                     "value": 1.2
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(response.json(), {"detail": "You do not have permission to perform this action."})
@@ -68,7 +66,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                     "name": "a test metric",
                     "value": 1.2
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"model_version_id": ['Invalid pk "aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa" - object does not exist.']})
@@ -84,7 +81,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                     "name": "a test metric",
                     "value": 1.2
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(response.json(), {"detail": "You do not have contributor access to this model."})
@@ -105,7 +101,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                     "name": "a test metric",
                     "value": 1.2
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -129,7 +124,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                     "name": "a test metric",
                     "value": 1.2
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
@@ -158,7 +152,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                     "name": "my_metric",
                     "value": 1.2
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         self.assertDictEqual(response.json(), {"created": "2046-01-01T12:34:56Z", "step": None, "value": 1.2})
@@ -188,7 +181,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                     "value": 1.2,
                     "mode": "point"
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
@@ -219,7 +211,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                     "mode": "point",
                     "step": 1
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"step": ["The step property cannot be set for Point type metrics."]})
@@ -238,7 +229,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                     "value": 1.2,
                     "step": 1
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"step": ["The step property cannot be set for Point type metrics."]})
@@ -257,7 +247,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                     "value": 1.2,
                     "mode": "series"
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"mode": ["Metric Key a test metric already exists and is of mode Point."]})
@@ -277,7 +266,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                     "name": "a test metric",
                     "value": 1.2
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"__all__": ["Metric Key a test metric is of mode Point and already has a value."]})
@@ -308,7 +296,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                     "value": 1.2,
                     "step": 2
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         self.assertDictEqual(response.json(), {"created": "2046-01-01T12:34:56Z", "step": 2, "value": 1.2})
@@ -336,7 +323,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                     "value": 1.2,
                     "step": 1
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"step": ["This metric has already been set for this step."]})
@@ -359,7 +345,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                     "name": "another metric",
                     "value": 1.2,
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"step": ["Cannot add a metric value without a step for metric key another metric because it already has metric values with steps set."]})
@@ -383,7 +368,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                     "value": 1.2,
                     "step": 1
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"step": ["Cannot add a metric value with step set for metric key another metric because it already has metric values with no step set."]})
@@ -409,7 +393,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                         }
                     ]
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(response.json(), {"detail": "You do not have permission to perform this action."})
@@ -433,7 +416,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                         }
                     ]
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"model_version_id": ['Invalid pk "aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa" - object does not exist.']})
@@ -459,7 +441,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                         }
                     ]
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(response.json(), {"detail": "You do not have contributor access to this model."})
@@ -489,7 +470,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                         }
                     ]
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -517,7 +497,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                         }
                     ]
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"metrics": {"1": {"__all__": ["Cannot send multiple values at once for the same name (some metric)."]}}})
@@ -548,7 +527,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                         }
                     ]
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         self.assertDictEqual(response.json(), {"metrics": [{"value": 12.0}, {"value": 3.0}]})
@@ -593,7 +571,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                         }
                     ]
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         self.assertDictEqual(response.json(), {"metrics": [{"value": 12.0}, {"value": 3.0}]})
@@ -645,7 +622,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                         }
                     ]
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         self.assertDictEqual(response.json(), {"step": 3, "metrics": [{"value": 12.0}, {"value": 3.0}]})
@@ -694,7 +670,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                         }
                     ]
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"metrics": {
@@ -722,7 +697,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                         }
                     ]
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -750,7 +724,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                         }
                     ]
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"metrics": {"0": {"mode": ["Metric Key a test metric already exists and is of mode Point."]}}})
@@ -776,7 +749,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                         }
                     ]
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"metrics": {"0": {"step": ["This metric has already been set for this step."]}}})
@@ -820,7 +792,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                         }
                     ]
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -863,7 +834,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                         }
                     ]
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"metrics": {"0": {"step": ["Cannot add a metric value without a step for metric key another metric because it already has metric values with steps set."]}}})
@@ -891,7 +861,6 @@ class TestMetricsAPI(FixtureAPITestCase):
                         }
                     ]
                 },
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"metrics": {"0": {"step": ["Cannot add a metric value with step set for metric key another metric because it already has metric values with no step set."]}}})
diff --git a/arkindex/training/tests/test_model_api.py b/arkindex/training/tests/test_model_api.py
index 6a7fce49213e6e3e970893ff8b96bfb521db26f0..1a4da13d1c60a5146891ee6f74c7e242a0ae6bd5 100644
--- a/arkindex/training/tests/test_model_api.py
+++ b/arkindex/training/tests/test_model_api.py
@@ -448,7 +448,6 @@ class TestModelAPI(FixtureAPITestCase):
             response = self.client.put(
                 reverse("api:model-retrieve", kwargs={"pk": str(self.model1.id)}),
                 {"name": "new name", "description": "test"},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
@@ -464,7 +463,6 @@ class TestModelAPI(FixtureAPITestCase):
             response = self.client.put(
                 reverse("api:model-retrieve", kwargs={"pk": str(self.model1.id)}),
                 {"name": self.model2.name, "description": "", "public": True},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"name": ["A model with this name already exists"]})
@@ -488,7 +486,6 @@ class TestModelAPI(FixtureAPITestCase):
                     response = self.client.put(
                         reverse("api:model-retrieve", kwargs={"pk": str(self.model1.id)}),
                         {"name": "new name", "description": "test", "archived": new_value},
-                        format="json",
                     )
                     self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -514,7 +511,6 @@ class TestModelAPI(FixtureAPITestCase):
                     response = self.client.put(
                         reverse("api:model-retrieve", kwargs={"pk": str(self.model1.id)}),
                         {"name": "new name", "description": "test", "archived": new_value},
-                        format="json",
                     )
                     self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -539,7 +535,6 @@ class TestModelAPI(FixtureAPITestCase):
             response = self.client.put(
                 reverse("api:model-retrieve", kwargs={"pk": str(self.model1.id)}),
                 {"name": "new name", "description": "", "public": True},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.model1.refresh_from_db()
@@ -586,7 +581,6 @@ class TestModelAPI(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:model-retrieve", kwargs={"pk": str(self.model1.id)}),
                 {"description": "test"},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
@@ -603,7 +597,6 @@ class TestModelAPI(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:model-retrieve", kwargs={"pk": str(self.model1.id)}),
                 {"description": "new desc", "public": True},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.model1.refresh_from_db()
@@ -642,7 +635,6 @@ class TestModelAPI(FixtureAPITestCase):
                     response = self.client.patch(
                         reverse("api:model-retrieve", kwargs={"pk": str(self.model1.id)}),
                         {"archived": new_value},
-                        format="json",
                     )
                     self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -668,7 +660,6 @@ class TestModelAPI(FixtureAPITestCase):
                     response = self.client.patch(
                         reverse("api:model-retrieve", kwargs={"pk": str(self.model1.id)}),
                         {"archived": new_value},
-                        format="json",
                     )
                     self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -700,7 +691,6 @@ class TestModelAPI(FixtureAPITestCase):
                     "description": "description",
                     "configuration": {"hello": "this is me"},
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
@@ -748,7 +738,6 @@ class TestModelAPI(FixtureAPITestCase):
                 response = self.client.post(
                     reverse("api:model-versions", kwargs={"pk": str(self.model1.id)}),
                     {},
-                    format="json"
                 )
                 self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         data = response.json()
@@ -783,7 +772,6 @@ class TestModelAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:model-versions", kwargs={"pk": str(self.model1.id)}),
                 {"tag": ""},
-                format="json",
             )
 
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -798,7 +786,6 @@ class TestModelAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:model-versions", kwargs={"pk": str(self.model1.id)}),
                 {"tag": "tagged"},
-                format="json",
             )
 
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -826,7 +813,6 @@ class TestModelAPI(FixtureAPITestCase):
                         "description": "description",
                         "configuration": {"hello": "this is me"},
                     },
-                    format="json",
                 )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         data = response.json()
@@ -860,7 +846,6 @@ class TestModelAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:model-versions", kwargs={"pk": str(self.model1.id)}),
                 {"tag": self.model_version2.tag},
-                format="json",
             )
 
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -887,7 +872,6 @@ class TestModelAPI(FixtureAPITestCase):
                         # self.model_version3 belongs to self.model2
                         "parent": str(self.model_version3.id)
                     },
-                    format="json",
                 )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         data = response.json()
@@ -933,7 +917,6 @@ class TestModelAPI(FixtureAPITestCase):
                         # self.model_version3 belongs to self.model2
                         "parent": str(self.model_version3.id)
                     },
-                    format="json",
                 )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertEqual(filter_rights_mock.call_count, 1)
@@ -948,7 +931,6 @@ class TestModelAPI(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:model-versions", kwargs={"pk": str(self.model1.id)}),
                 {"hash": self.model_version5.hash},
-                format="json",
             )
 
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
@@ -1222,7 +1204,6 @@ class TestModelAPI(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:model-version-retrieve", kwargs={"pk": str(self.model_version1.id)}),
                 request,
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -1268,7 +1249,6 @@ class TestModelAPI(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:model-version-retrieve", kwargs={"pk": str(self.model_version3.id)}),
                 request,
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK, response.json())
 
@@ -1305,7 +1285,6 @@ class TestModelAPI(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:model-version-retrieve", kwargs={"pk": str(self.model_version3.id)}),
                 {"parent": None},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -1337,7 +1316,6 @@ class TestModelAPI(FixtureAPITestCase):
                 reverse("api:model-version-retrieve", kwargs={"pk": str(self.model_version3.id)}),
                 # self.model_version3 is a version of self.model2, while self.model_version1 belongs to self.model1
                 {"parent": str(self.model_version1.id)},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -1372,7 +1350,6 @@ class TestModelAPI(FixtureAPITestCase):
                 reverse("api:model-version-retrieve", kwargs={"pk": str(self.model_version3.id)}),
                 # self.model_version3 is a version of self.model2, while self.model_version1 belongs to self.model1
                 {"parent": str(self.model_version1.id)},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -1397,7 +1374,6 @@ class TestModelAPI(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:model-version-retrieve", kwargs={"pk": str(self.model_version3.id)}),
                 {"hash": self.model_version4.hash},
-                format="json"
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -1420,7 +1396,6 @@ class TestModelAPI(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:model-version-retrieve", kwargs={"pk": str(self.model_version1.id)}),
                 {"archive_hash": "d" * 32, "hash": "e" * 32, "size": 32, "state": "available"},
-                format="json"
             )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -1444,7 +1419,6 @@ class TestModelAPI(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:model-version-retrieve", kwargs={"pk": str(self.model_version1.id)}),
                 {"archive_hash": "d" * 32, "hash": "e" * 32, "size": 32, "state": "available"},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"size": ["Uploaded file size is 31 bytes, expected 32 bytes"]})
@@ -1467,7 +1441,6 @@ class TestModelAPI(FixtureAPITestCase):
             response = self.client.patch(
                 reverse("api:model-version-retrieve", kwargs={"pk": str(self.model_version3.id)}),
                 {"archive_hash": "d" * 32, "hash": "e" * 32, "size": 32},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
@@ -1496,7 +1469,6 @@ class TestModelAPI(FixtureAPITestCase):
                     "description": "other description",
                     "configuration": {"hi": "Who am I?"},
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
@@ -1525,7 +1497,6 @@ class TestModelAPI(FixtureAPITestCase):
                     "description": "other description",
                     "configuration": {"hi": "Who am I ?"},
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
 
diff --git a/arkindex/users/tests/test_password_reset.py b/arkindex/users/tests/test_password_reset.py
index 517dc451803e3edd2535ed372468a567f00f26a9..b432358da92606e855689dd1311337d86fcdb3a0 100644
--- a/arkindex/users/tests/test_password_reset.py
+++ b/arkindex/users/tests/test_password_reset.py
@@ -14,7 +14,6 @@ class TestPasswordReset(FixtureAPITestCase):
         resp = self.client.post(
             reverse("api:password-reset"),
             data={"email": self.user.email},
-            format="json",
         )
         self.assertEqual(resp.status_code, status.HTTP_201_CREATED)
         self.assertEqual(len(mail.outbox), 1)
@@ -28,7 +27,6 @@ class TestPasswordReset(FixtureAPITestCase):
         resp = self.client.post(
             reverse("api:password-reset"),
             data={"email": "nopenopenope@nope.no"},
-            format="json",
         )
         self.assertEqual(resp.status_code, status.HTTP_201_CREATED)
         self.assertEqual(len(mail.outbox), 0)
@@ -40,7 +38,6 @@ class TestPasswordReset(FixtureAPITestCase):
         resp = self.client.post(
             reverse("api:password-reset"),
             data={"email": "nope"},
-            format="json",
         )
         self.assertEqual(resp.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertEqual(len(mail.outbox), 0)
@@ -55,7 +52,6 @@ class TestPasswordReset(FixtureAPITestCase):
                 "token": "t0k3n",
                 "password": "S3cr37Pa$$w0rd"
             },
-            format="json",
         )
         self.assertEqual(resp.status_code, status.HTTP_201_CREATED)
         self.user.refresh_from_db()
@@ -73,7 +69,6 @@ class TestPasswordReset(FixtureAPITestCase):
                 "token": "t0k3n",
                 "password": "S3cr37Pa$$w0rd"
             },
-            format="json",
         )
         self.assertEqual(resp.status_code, status.HTTP_400_BAD_REQUEST)
         self.user.refresh_from_db()
@@ -96,7 +91,6 @@ class TestPasswordReset(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:password-reset-confirm"),
                 data={"uidb64": urlsafe_base64_encode(str(self.user.id).encode()), "token": "t0k3n", "password": pwd},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
             self.assertEqual(response.json(), {"password": messages})
diff --git a/arkindex/users/tests/test_registration.py b/arkindex/users/tests/test_registration.py
index 17de7a3a798df534b3eb4ed4ab07cbde833e95d1..8c289177aa6d35319c66647861548ce51c8c57f6 100644
--- a/arkindex/users/tests/test_registration.py
+++ b/arkindex/users/tests/test_registration.py
@@ -30,7 +30,6 @@ class TestRegistration(FixtureAPITestCase):
         response = self.client.put(
             reverse("api:user-retrieve"),
             data={"password": "N€wP4$5w0Rd"},
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
 
@@ -66,7 +65,6 @@ class TestRegistration(FixtureAPITestCase):
         response = self.client.patch(
             reverse("api:user-retrieve"),
             data={"password": "N€wP4$5w0Rd"},
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.user.refresh_from_db()
@@ -75,7 +73,6 @@ class TestRegistration(FixtureAPITestCase):
         # Ensure client session is still valid
         response = self.client.get(
             reverse("api:user-retrieve"),
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
 
@@ -84,7 +81,6 @@ class TestRegistration(FixtureAPITestCase):
         response = self.client.patch(
             reverse("api:user-retrieve"),
             data={"password": "email"},
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -100,7 +96,6 @@ class TestRegistration(FixtureAPITestCase):
         response = self.client.patch(
             reverse("api:user-retrieve"),
             data={"display_name": "There was a typo in my name"},
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.user.refresh_from_db()
@@ -116,7 +111,6 @@ class TestRegistration(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:user-login"),
             data={"email": "lol@lol.lol", "password": "password"},
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(response.json(), {"detail": "Incorrect authentication credentials."})
@@ -126,7 +120,6 @@ class TestRegistration(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:user-login"),
             data={"email": "email@address.com", "password": "wrongpassword"},
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_403_FORBIDDEN)
         self.assertDictEqual(response.json(), {"detail": "Incorrect authentication credentials."})
@@ -139,7 +132,6 @@ class TestRegistration(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:user-login"),
             data={"email": "eMaIL@adDreSs.cOm", "password": "P4$5w0Rd"},
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         self.assertTrue(auth.get_user(self.client).is_authenticated)
@@ -149,7 +141,6 @@ class TestRegistration(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:user-login"),
             data={"email": "email@address.com", "password": "P4$5w0Rd"},
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         self.assertTrue(auth.get_user(self.client).is_authenticated)
@@ -168,7 +159,6 @@ class TestRegistration(FixtureAPITestCase):
                 "email": "newuser@example.com",
                 "token": default_token_generator.make_token(newuser),
             },
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
@@ -220,7 +210,6 @@ class TestRegistration(FixtureAPITestCase):
                     "email": "newuser@example.com",
                     "token": default_token_generator.make_token(newuser),
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
 
@@ -243,7 +232,6 @@ class TestRegistration(FixtureAPITestCase):
                     "email": "newuser@example.com",
                     "token": default_token_generator.make_token(newuser),
                 },
-                format="json",
             )
 
     def test_email_verification_no_password(self):
@@ -260,7 +248,6 @@ class TestRegistration(FixtureAPITestCase):
                     "email": "newuser@example.com",
                     "token": default_token_generator.make_token(newuser),
                 },
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         newuser.refresh_from_db()
@@ -279,7 +266,6 @@ class TestRegistration(FixtureAPITestCase):
                 "email": "user@user.fr",
                 "token": default_token_generator.make_token(user),
             },
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         # Assert no trial corpus is created
@@ -290,7 +276,6 @@ class TestRegistration(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:verify-email"),
             data={},
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -302,7 +287,6 @@ class TestRegistration(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:verify-email"),
             data={"email": self.user.email, "token": "AAAA"},
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -313,7 +297,6 @@ class TestRegistration(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:verify-email"),
             data={"email": "a@bc.de", "token": default_token_generator.make_token(self.user)},
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -326,7 +309,6 @@ class TestRegistration(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:user-new"),
             data={"display_name": "New user", "email": "newuser@example.com"},
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         self.assertTrue(auth.get_user(self.client).is_authenticated)
@@ -343,7 +325,6 @@ class TestRegistration(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:user-new"),
             data={"display_name": "New user", "email": "newuser@example.com", "password": "myVerySecretPassword"},
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)
         self.assertTrue(auth.get_user(self.client).is_authenticated)
@@ -366,7 +347,6 @@ class TestRegistration(FixtureAPITestCase):
             response = self.client.post(
                 reverse("api:user-new"),
                 data={"display_name": "New user", "email": "newuser@example.com", "password": pwd},
-                format="json",
             )
             self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
             self.assertEqual(response.json(), {"password": messages})
@@ -379,7 +359,6 @@ class TestRegistration(FixtureAPITestCase):
                 "email": "",
                 "password": ""
             },
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {
@@ -393,7 +372,6 @@ class TestRegistration(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:user-new"),
             data={"email": "newuser@example.com", "password": "myVerySecretPassword"},
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertListEqual(response.json(), ["Registration has been disabled on this instance."])
@@ -404,7 +382,6 @@ class TestRegistration(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:user-new"),
             data={"display_name": "New user", "email": email, "password": "myVerySecretPassword"},
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"email": ["A user with this email address already exists."]})
@@ -415,7 +392,6 @@ class TestRegistration(FixtureAPITestCase):
         response = self.client.post(
             reverse("api:user-new"),
             data={"display_name": "New user", "email": email, "password": "myVerySecretPassword"},
-            format="json",
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertDictEqual(response.json(), {"email": ["A user with this email address already exists."]})