diff --git a/flame_hub/_core_client.py b/flame_hub/_core_client.py
index c1914c2..b9c8f33 100644
--- a/flame_hub/_core_client.py
+++ b/flame_hub/_core_client.py
@@ -227,7 +227,7 @@ class CreateAnalysis(BaseModel):
     image_command_arguments: t.Annotated[
         list[MasterImageCommandArgument],
         Field(default_factory=list),
-        BeforeValidator(lambda value: [] if value is None else value),
+        BeforeValidator(lambda args: [] if args is None else ensure_position_none(args)),
     ]
 
 
@@ -258,7 +258,13 @@ class UpdateAnalysis(BaseModel):
     description: str | None | UNSET_T = UNSET
     name: str | None | UNSET_T = UNSET
     master_image_id: t.Annotated[uuid.UUID | None | UNSET_T, Field(), WrapValidator(uuid_validator)] = UNSET
-    image_command_arguments: list[MasterImageCommandArgument] | UNSET_T = UNSET
+    image_command_arguments: (
+        t.Annotated[
+            list[MasterImageCommandArgument],
+            BeforeValidator(lambda args: ensure_position_none(args)),
+        ]
+        | UNSET_T
+    ) = UNSET
 
 
 AnalysisCommand = t.Literal[
diff --git a/tests/test_core.py b/tests/test_core.py
index 8f017b7..a65df66 100644
--- a/tests/test_core.py
+++ b/tests/test_core.py
@@ -1,4 +1,5 @@
 import os
+import random
 import string
 import typing as t
 
@@ -100,7 +101,15 @@ def project_node_includables():
 
 @pytest.fixture()
 def analysis(core_client, project, master_image):
-    new_analysis = core_client.create_analysis(project, master_image_id=master_image.id)
+    args = [
+        {"value": next_random_string()},
+        {"value": next_random_string(), "position": random.choice(("before", "after"))},
+    ]
+    new_analysis = core_client.create_analysis(
+        project,
+        master_image_id=master_image.id,
+        image_command_arguments=args,
+    )
     yield new_analysis
     core_client.delete_analysis(new_analysis)
 
@@ -402,11 +411,16 @@ def test_get_analysis_not_found(core_client):
 
 
 def test_update_analysis(core_client, analysis):
+    args = [
+        {"value": next_random_string()},
+        {"value": next_random_string(), "position": random.choice(("before", "after"))},
+    ]
     new_name = next_random_string()
-    new_analysis = core_client.update_analysis(analysis.id, name=new_name)
+    new_analysis = core_client.update_analysis(analysis.id, name=new_name, image_command_arguments=args)
 
     assert analysis != new_analysis
     assert new_analysis.name == new_name
+    assert new_analysis.image_command_arguments == args  # Note that args is modified during updating the analysis.
 
 
 def test_unlock_analysis(core_client, configured_analysis):