diff --git a/api/controllers/common/fields.py b/api/controllers/common/fields.py
index df9de825de..c16a23fac8 100644
--- a/api/controllers/common/fields.py
+++ b/api/controllers/common/fields.py
@@ -1,62 +1,59 @@
-from flask_restx import Api, Namespace, fields
+from __future__ import annotations
 
-from libs.helper import AppIconUrlField
+from typing import Any, TypeAlias
 
-parameters__system_parameters = {
-    "image_file_size_limit": fields.Integer,
-    "video_file_size_limit": fields.Integer,
-    "audio_file_size_limit": fields.Integer,
-    "file_size_limit": fields.Integer,
-    "workflow_file_upload_limit": fields.Integer,
-}
+from pydantic import BaseModel, ConfigDict, computed_field
+
+from core.file import helpers as file_helpers
+from models.model import IconType
+
+JSONValue: TypeAlias = str | int | float | bool | None | dict[str, Any] | list[Any]
+JSONObject: TypeAlias = dict[str, Any]
 
 
-def build_system_parameters_model(api_or_ns: Api | Namespace):
-    """Build the system parameters model for the API or Namespace."""
-    return api_or_ns.model("SystemParameters", parameters__system_parameters)
+class SystemParameters(BaseModel):
+    image_file_size_limit: int
+    video_file_size_limit: int
+    audio_file_size_limit: int
+    file_size_limit: int
+    workflow_file_upload_limit: int
 
 
-parameters_fields = {
-    "opening_statement": fields.String,
-    "suggested_questions": fields.Raw,
-    "suggested_questions_after_answer": fields.Raw,
-    "speech_to_text": fields.Raw,
-    "text_to_speech": fields.Raw,
-    "retriever_resource": fields.Raw,
-    "annotation_reply": fields.Raw,
-    "more_like_this": fields.Raw,
-    "user_input_form": fields.Raw,
-    "sensitive_word_avoidance": fields.Raw,
-    "file_upload": fields.Raw,
-    "system_parameters": fields.Nested(parameters__system_parameters),
-}
+class Parameters(BaseModel):
+    opening_statement: str | None = None
+    suggested_questions: list[str]
+    suggested_questions_after_answer: JSONObject
+    speech_to_text: JSONObject
+    text_to_speech: JSONObject
+    retriever_resource: JSONObject
+    annotation_reply: JSONObject
+    more_like_this: JSONObject
+    user_input_form: list[JSONObject]
+    sensitive_word_avoidance: JSONObject
+    file_upload: JSONObject
+    system_parameters: SystemParameters
 
 
-def build_parameters_model(api_or_ns: Api | Namespace):
-    """Build the parameters model for the API or Namespace."""
-    copied_fields = parameters_fields.copy()
-    copied_fields["system_parameters"] = fields.Nested(build_system_parameters_model(api_or_ns))
-    return api_or_ns.model("Parameters", copied_fields)
+class Site(BaseModel):
+    model_config = ConfigDict(from_attributes=True)
 
+    title: str
+    chat_color_theme: str | None = None
+    chat_color_theme_inverted: bool
+    icon_type: str | None = None
+    icon: str | None = None
+    icon_background: str | None = None
+    description: str | None = None
+    copyright: str | None = None
+    privacy_policy: str | None = None
+    custom_disclaimer: str | None = None
+    default_language: str
+    show_workflow_steps: bool
+    use_icon_as_answer_icon: bool
 
-site_fields = {
-    "title": fields.String,
-    "chat_color_theme": fields.String,
-    "chat_color_theme_inverted": fields.Boolean,
-    "icon_type": fields.String,
-    "icon": fields.String,
-    "icon_background": fields.String,
-    "icon_url": AppIconUrlField,
-    "description": fields.String,
-    "copyright": fields.String,
-    "privacy_policy": fields.String,
-    "custom_disclaimer": fields.String,
-    "default_language": fields.String,
-    "show_workflow_steps": fields.Boolean,
-    "use_icon_as_answer_icon": fields.Boolean,
-}
-
-
-def build_site_model(api_or_ns: Api | Namespace):
-    """Build the site model for the API or Namespace."""
-    return api_or_ns.model("Site", site_fields)
+    @computed_field(return_type=str | None)  # type: ignore
+    @property
+    def icon_url(self) -> str | None:
+        if self.icon and self.icon_type == IconType.IMAGE:
+            return file_helpers.get_signed_file_url(self.icon)
+        return None
diff --git a/api/controllers/console/explore/parameter.py b/api/controllers/console/explore/parameter.py
index 9c6b2aedfb..660a4d5aea 100644
--- a/api/controllers/console/explore/parameter.py
+++ b/api/controllers/console/explore/parameter.py
@@ -1,5 +1,3 @@
-from flask_restx import marshal_with
-
 from controllers.common import fields
 from controllers.console import console_ns
 from controllers.console.app.error import AppUnavailableError
@@ -13,7 +11,6 @@ from services.app_service import AppService
 class AppParameterApi(InstalledAppResource):
     """Resource for app variables."""
 
-    @marshal_with(fields.parameters_fields)
     def get(self, installed_app: InstalledApp):
         """Retrieve app parameters."""
         app_model = installed_app.app
@@ -37,7 +34,8 @@ class AppParameterApi(InstalledAppResource):
 
             user_input_form = features_dict.get("user_input_form", [])
 
-        return get_parameters_from_feature_dict(features_dict=features_dict, user_input_form=user_input_form)
+        parameters = get_parameters_from_feature_dict(features_dict=features_dict, user_input_form=user_input_form)
+        return fields.Parameters.model_validate(parameters).model_dump(mode="json")
 
 
 @console_ns.route("/installed-apps/<uuid:installed_app_id>/meta", endpoint="installed_app_meta")
diff --git a/api/controllers/service_api/app/annotation.py b/api/controllers/service_api/app/annotation.py
index 63c373b50f..85ac9336d6 100644
--- a/api/controllers/service_api/app/annotation.py
+++ b/api/controllers/service_api/app/annotation.py
@@ -1,7 +1,7 @@
 from typing import Literal
 
 from flask import request
-from flask_restx import Api, Namespace, Resource, fields
+from flask_restx import Namespace, Resource, fields
 from flask_restx.api import HTTPStatus
 from pydantic import BaseModel, Field
 
@@ -92,7 +92,7 @@ annotation_list_fields = {
 }
 
 
-def build_annotation_list_model(api_or_ns: Api | Namespace):
+def build_annotation_list_model(api_or_ns: Namespace):
     """Build the annotation list model for the API or Namespace."""
     copied_annotation_list_fields = annotation_list_fields.copy()
     copied_annotation_list_fields["data"] = fields.List(fields.Nested(build_annotation_model(api_or_ns)))
diff --git a/api/controllers/service_api/app/app.py b/api/controllers/service_api/app/app.py
index 25d7ccccec..562f5e33cc 100644
--- a/api/controllers/service_api/app/app.py
+++ b/api/controllers/service_api/app/app.py
@@ -1,6 +1,6 @@
 from flask_restx import Resource
 
-from controllers.common.fields import build_parameters_model
+from controllers.common.fields import Parameters
 from controllers.service_api import service_api_ns
 from controllers.service_api.app.error import AppUnavailableError
 from controllers.service_api.wraps import validate_app_token
@@ -23,7 +23,6 @@ class AppParameterApi(Resource):
         }
     )
     @validate_app_token
-    @service_api_ns.marshal_with(build_parameters_model(service_api_ns))
     def get(self, app_model: App):
         """Retrieve app parameters.
 
@@ -45,7 +44,8 @@ class AppParameterApi(Resource):
 
             user_input_form = features_dict.get("user_input_form", [])
 
-        return get_parameters_from_feature_dict(features_dict=features_dict, user_input_form=user_input_form)
+        parameters = get_parameters_from_feature_dict(features_dict=features_dict, user_input_form=user_input_form)
+        return Parameters.model_validate(parameters).model_dump(mode="json")
 
 
 @service_api_ns.route("/meta")
diff --git a/api/controllers/service_api/app/site.py b/api/controllers/service_api/app/site.py
index 9f8324a84e..8b47a887bb 100644
--- a/api/controllers/service_api/app/site.py
+++ b/api/controllers/service_api/app/site.py
@@ -1,7 +1,7 @@
 from flask_restx import Resource
 from werkzeug.exceptions import Forbidden
 
-from controllers.common.fields import build_site_model
+from controllers.common.fields import Site as SiteResponse
 from controllers.service_api import service_api_ns
 from controllers.service_api.wraps import validate_app_token
 from extensions.ext_database import db
@@ -23,7 +23,6 @@ class AppSiteApi(Resource):
         }
     )
     @validate_app_token
-    @service_api_ns.marshal_with(build_site_model(service_api_ns))
     def get(self, app_model: App):
         """Retrieve app site info.
 
@@ -38,4 +37,4 @@ class AppSiteApi(Resource):
         if app_model.tenant.status == TenantStatus.ARCHIVE:
             raise Forbidden()
 
-        return site
+        return SiteResponse.model_validate(site).model_dump(mode="json")
diff --git a/api/controllers/service_api/app/workflow.py b/api/controllers/service_api/app/workflow.py
index 4964888fd6..6a549fc926 100644
--- a/api/controllers/service_api/app/workflow.py
+++ b/api/controllers/service_api/app/workflow.py
@@ -3,7 +3,7 @@ from typing import Any, Literal
 
 from dateutil.parser import isoparse
 from flask import request
-from flask_restx import Api, Namespace, Resource, fields
+from flask_restx import Namespace, Resource, fields
 from pydantic import BaseModel, Field
 from sqlalchemy.orm import Session, sessionmaker
 from werkzeug.exceptions import BadRequest, InternalServerError, NotFound
@@ -78,7 +78,7 @@ workflow_run_fields = {
 }
 
 
-def build_workflow_run_model(api_or_ns: Api | Namespace):
+def build_workflow_run_model(api_or_ns: Namespace):
     """Build the workflow run model for the API or Namespace."""
     return api_or_ns.model("WorkflowRun", workflow_run_fields)
 
diff --git a/api/controllers/web/app.py b/api/controllers/web/app.py
index db3b93a4dc..62ea532eac 100644
--- a/api/controllers/web/app.py
+++ b/api/controllers/web/app.py
@@ -1,7 +1,7 @@
 import logging
 
 from flask import request
-from flask_restx import Resource, marshal_with
+from flask_restx import Resource
 from pydantic import BaseModel, ConfigDict, Field
 from werkzeug.exceptions import Unauthorized
 
@@ -50,7 +50,6 @@ class AppParameterApi(WebApiResource):
             500: "Internal Server Error",
         }
     )
-    @marshal_with(fields.parameters_fields)
     def get(self, app_model: App, end_user):
         """Retrieve app parameters."""
         if app_model.mode in {AppMode.ADVANCED_CHAT, AppMode.WORKFLOW}:
@@ -69,7 +68,8 @@ class AppParameterApi(WebApiResource):
 
             user_input_form = features_dict.get("user_input_form", [])
 
-        return get_parameters_from_feature_dict(features_dict=features_dict, user_input_form=user_input_form)
+        parameters = get_parameters_from_feature_dict(features_dict=features_dict, user_input_form=user_input_form)
+        return fields.Parameters.model_validate(parameters).model_dump(mode="json")
 
 
 @web_ns.route("/meta")
diff --git a/api/fields/annotation_fields.py b/api/fields/annotation_fields.py
index 38835d5ac7..e69306dcb2 100644
--- a/api/fields/annotation_fields.py
+++ b/api/fields/annotation_fields.py
@@ -1,4 +1,4 @@
-from flask_restx import Api, Namespace, fields
+from flask_restx import Namespace, fields
 
 from libs.helper import TimestampField
 
@@ -12,7 +12,7 @@ annotation_fields = {
 }
 
 
-def build_annotation_model(api_or_ns: Api | Namespace):
+def build_annotation_model(api_or_ns: Namespace):
     """Build the annotation model for the API or Namespace."""
     return api_or_ns.model("Annotation", annotation_fields)
 
diff --git a/api/fields/conversation_fields.py b/api/fields/conversation_fields.py
index ecc267cf38..e4ca2e7a42 100644
--- a/api/fields/conversation_fields.py
+++ b/api/fields/conversation_fields.py
@@ -1,4 +1,4 @@
-from flask_restx import Api, Namespace, fields
+from flask_restx import Namespace, fields
 
 from fields.member_fields import simple_account_fields
 from libs.helper import TimestampField
@@ -46,7 +46,7 @@ message_file_fields = {
 }
 
 
-def build_message_file_model(api_or_ns: Api | Namespace):
+def build_message_file_model(api_or_ns: Namespace):
     """Build the message file fields for the API or Namespace."""
     return api_or_ns.model("MessageFile", message_file_fields)
 
@@ -217,7 +217,7 @@ conversation_infinite_scroll_pagination_fields = {
 }
 
 
-def build_conversation_infinite_scroll_pagination_model(api_or_ns: Api | Namespace):
+def build_conversation_infinite_scroll_pagination_model(api_or_ns: Namespace):
     """Build the conversation infinite scroll pagination model for the API or Namespace."""
     simple_conversation_model = build_simple_conversation_model(api_or_ns)
 
@@ -226,11 +226,11 @@ def build_conversation_infinite_scroll_pagination_model(api_or_ns: Api | Namespa
     return api_or_ns.model("ConversationInfiniteScrollPagination", copied_fields)
 
 
-def build_conversation_delete_model(api_or_ns: Api | Namespace):
+def build_conversation_delete_model(api_or_ns: Namespace):
     """Build the conversation delete model for the API or Namespace."""
     return api_or_ns.model("ConversationDelete", conversation_delete_fields)
 
 
-def build_simple_conversation_model(api_or_ns: Api | Namespace):
+def build_simple_conversation_model(api_or_ns: Namespace):
     """Build the simple conversation model for the API or Namespace."""
     return api_or_ns.model("SimpleConversation", simple_conversation_fields)
diff --git a/api/fields/conversation_variable_fields.py b/api/fields/conversation_variable_fields.py
index 7d5e311591..c55014a368 100644
--- a/api/fields/conversation_variable_fields.py
+++ b/api/fields/conversation_variable_fields.py
@@ -1,4 +1,4 @@
-from flask_restx import Api, Namespace, fields
+from flask_restx import Namespace, fields
 
 from libs.helper import TimestampField
 
@@ -29,12 +29,12 @@ conversation_variable_infinite_scroll_pagination_fields = {
 }
 
 
-def build_conversation_variable_model(api_or_ns: Api | Namespace):
+def build_conversation_variable_model(api_or_ns: Namespace):
     """Build the conversation variable model for the API or Namespace."""
     return api_or_ns.model("ConversationVariable", conversation_variable_fields)
 
 
-def build_conversation_variable_infinite_scroll_pagination_model(api_or_ns: Api | Namespace):
+def build_conversation_variable_infinite_scroll_pagination_model(api_or_ns: Namespace):
     """Build the conversation variable infinite scroll pagination model for the API or Namespace."""
     # Build the nested variable model first
     conversation_variable_model = build_conversation_variable_model(api_or_ns)
diff --git a/api/fields/end_user_fields.py b/api/fields/end_user_fields.py
index ea43e3b5fd..5389b0213a 100644
--- a/api/fields/end_user_fields.py
+++ b/api/fields/end_user_fields.py
@@ -1,4 +1,4 @@
-from flask_restx import Api, Namespace, fields
+from flask_restx import Namespace, fields
 
 simple_end_user_fields = {
     "id": fields.String,
@@ -8,5 +8,5 @@ simple_end_user_fields = {
 }
 
 
-def build_simple_end_user_model(api_or_ns: Api | Namespace):
+def build_simple_end_user_model(api_or_ns: Namespace):
     return api_or_ns.model("SimpleEndUser", simple_end_user_fields)
diff --git a/api/fields/file_fields.py b/api/fields/file_fields.py
index a707500445..70138404c7 100644
--- a/api/fields/file_fields.py
+++ b/api/fields/file_fields.py
@@ -1,4 +1,4 @@
-from flask_restx import Api, Namespace, fields
+from flask_restx import Namespace, fields
 
 from libs.helper import TimestampField
 
@@ -14,7 +14,7 @@ upload_config_fields = {
 }
 
 
-def build_upload_config_model(api_or_ns: Api | Namespace):
+def build_upload_config_model(api_or_ns: Namespace):
     """Build the upload config model for the API or Namespace.
 
     Args:
@@ -39,7 +39,7 @@ file_fields = {
 }
 
 
-def build_file_model(api_or_ns: Api | Namespace):
+def build_file_model(api_or_ns: Namespace):
     """Build the file model for the API or Namespace.
 
     Args:
@@ -57,7 +57,7 @@ remote_file_info_fields = {
 }
 
 
-def build_remote_file_info_model(api_or_ns: Api | Namespace):
+def build_remote_file_info_model(api_or_ns: Namespace):
     """Build the remote file info model for the API or Namespace.
 
     Args:
@@ -81,7 +81,7 @@ file_fields_with_signed_url = {
 }
 
 
-def build_file_with_signed_url_model(api_or_ns: Api | Namespace):
+def build_file_with_signed_url_model(api_or_ns: Namespace):
     """Build the file with signed URL model for the API or Namespace.
 
     Args:
diff --git a/api/fields/member_fields.py b/api/fields/member_fields.py
index 08e38a6931..25160927e6 100644
--- a/api/fields/member_fields.py
+++ b/api/fields/member_fields.py
@@ -1,4 +1,4 @@
-from flask_restx import Api, Namespace, fields
+from flask_restx import Namespace, fields
 
 from libs.helper import AvatarUrlField, TimestampField
 
@@ -9,7 +9,7 @@ simple_account_fields = {
 }
 
 
-def build_simple_account_model(api_or_ns: Api | Namespace):
+def build_simple_account_model(api_or_ns: Namespace):
     return api_or_ns.model("SimpleAccount", simple_account_fields)
 
 
diff --git a/api/fields/message_fields.py b/api/fields/message_fields.py
index a419da2e18..151ff6f826 100644
--- a/api/fields/message_fields.py
+++ b/api/fields/message_fields.py
@@ -1,4 +1,4 @@
-from flask_restx import Api, Namespace, fields
+from flask_restx import Namespace, fields
 
 from fields.conversation_fields import message_file_fields
 from libs.helper import TimestampField
@@ -10,7 +10,7 @@ feedback_fields = {
 }
 
 
-def build_feedback_model(api_or_ns: Api | Namespace):
+def build_feedback_model(api_or_ns: Namespace):
     """Build the feedback model for the API or Namespace."""
     return api_or_ns.model("Feedback", feedback_fields)
 
@@ -30,7 +30,7 @@ agent_thought_fields = {
 }
 
 
-def build_agent_thought_model(api_or_ns: Api | Namespace):
+def build_agent_thought_model(api_or_ns: Namespace):
     """Build the agent thought model for the API or Namespace."""
     return api_or_ns.model("AgentThought", agent_thought_fields)
 
diff --git a/api/fields/tag_fields.py b/api/fields/tag_fields.py
index d5b7c86a04..e359a4408c 100644
--- a/api/fields/tag_fields.py
+++ b/api/fields/tag_fields.py
@@ -1,4 +1,4 @@
-from flask_restx import Api, Namespace, fields
+from flask_restx import Namespace, fields
 
 dataset_tag_fields = {
     "id": fields.String,
@@ -8,5 +8,5 @@ dataset_tag_fields = {
 }
 
 
-def build_dataset_tag_fields(api_or_ns: Api | Namespace):
+def build_dataset_tag_fields(api_or_ns: Namespace):
     return api_or_ns.model("DataSetTag", dataset_tag_fields)
diff --git a/api/fields/workflow_app_log_fields.py b/api/fields/workflow_app_log_fields.py
index 4cbdf6f0ca..0ebc03a98c 100644
--- a/api/fields/workflow_app_log_fields.py
+++ b/api/fields/workflow_app_log_fields.py
@@ -1,4 +1,4 @@
-from flask_restx import Api, Namespace, fields
+from flask_restx import Namespace, fields
 
 from fields.end_user_fields import build_simple_end_user_model, simple_end_user_fields
 from fields.member_fields import build_simple_account_model, simple_account_fields
@@ -17,7 +17,7 @@ workflow_app_log_partial_fields = {
 }
 
 
-def build_workflow_app_log_partial_model(api_or_ns: Api | Namespace):
+def build_workflow_app_log_partial_model(api_or_ns: Namespace):
     """Build the workflow app log partial model for the API or Namespace."""
     workflow_run_model = build_workflow_run_for_log_model(api_or_ns)
     simple_account_model = build_simple_account_model(api_or_ns)
@@ -43,7 +43,7 @@ workflow_app_log_pagination_fields = {
 }
 
 
-def build_workflow_app_log_pagination_model(api_or_ns: Api | Namespace):
+def build_workflow_app_log_pagination_model(api_or_ns: Namespace):
     """Build the workflow app log pagination model for the API or Namespace."""
     # Build the nested partial model first
     workflow_app_log_partial_model = build_workflow_app_log_partial_model(api_or_ns)
diff --git a/api/fields/workflow_run_fields.py b/api/fields/workflow_run_fields.py
index 821ce62ecc..476025064f 100644
--- a/api/fields/workflow_run_fields.py
+++ b/api/fields/workflow_run_fields.py
@@ -1,4 +1,4 @@
-from flask_restx import Api, Namespace, fields
+from flask_restx import Namespace, fields
 
 from fields.end_user_fields import simple_end_user_fields
 from fields.member_fields import simple_account_fields
@@ -19,7 +19,7 @@ workflow_run_for_log_fields = {
 }
 
 
-def build_workflow_run_for_log_model(api_or_ns: Api | Namespace):
+def build_workflow_run_for_log_model(api_or_ns: Namespace):
     return api_or_ns.model("WorkflowRunForLog", workflow_run_for_log_fields)
 
 
diff --git a/api/models/account.py b/api/models/account.py
index 420e6adc6c..f7a9c20026 100644
--- a/api/models/account.py
+++ b/api/models/account.py
@@ -8,7 +8,7 @@ from uuid import uuid4
 import sqlalchemy as sa
 from flask_login import UserMixin
 from sqlalchemy import DateTime, String, func, select
-from sqlalchemy.orm import Mapped, Session, mapped_column
+from sqlalchemy.orm import Mapped, Session, mapped_column, validates
 from typing_extensions import deprecated
 
 from .base import TypeBase
@@ -116,6 +116,12 @@ class Account(UserMixin, TypeBase):
     role: TenantAccountRole | None = field(default=None, init=False)
     _current_tenant: "Tenant | None" = field(default=None, init=False)
 
+    @validates("status")
+    def _normalize_status(self, _key: str, value: str | AccountStatus) -> str:
+        if isinstance(value, AccountStatus):
+            return value.value
+        return value
+
     @property
     def is_password_set(self):
         return self.password is not None
diff --git a/api/tests/unit_tests/controllers/common/test_fields.py b/api/tests/unit_tests/controllers/common/test_fields.py
new file mode 100644
index 0000000000..d4dc13127d
--- /dev/null
+++ b/api/tests/unit_tests/controllers/common/test_fields.py
@@ -0,0 +1,69 @@
+import builtins
+from types import SimpleNamespace
+from unittest.mock import patch
+
+from flask.views import MethodView as FlaskMethodView
+
+_NEEDS_METHOD_VIEW_CLEANUP = False
+if not hasattr(builtins, "MethodView"):
+    builtins.MethodView = FlaskMethodView
+    _NEEDS_METHOD_VIEW_CLEANUP = True
+from controllers.common.fields import Parameters, Site
+from core.app.app_config.common.parameters_mapping import get_parameters_from_feature_dict
+from models.model import IconType
+
+
+def test_parameters_model_round_trip():
+    parameters = get_parameters_from_feature_dict(features_dict={}, user_input_form=[])
+
+    model = Parameters.model_validate(parameters)
+
+    assert model.model_dump(mode="json") == parameters
+
+
+def test_site_icon_url_uses_signed_url_for_image_icon():
+    site = SimpleNamespace(
+        title="Example",
+        chat_color_theme=None,
+        chat_color_theme_inverted=False,
+        icon_type=IconType.IMAGE,
+        icon="file-id",
+        icon_background=None,
+        description=None,
+        copyright=None,
+        privacy_policy=None,
+        custom_disclaimer=None,
+        default_language="en-US",
+        show_workflow_steps=True,
+        use_icon_as_answer_icon=False,
+    )
+
+    with patch("controllers.common.fields.file_helpers.get_signed_file_url", return_value="signed") as mock_helper:
+        model = Site.model_validate(site)
+
+        assert model.icon_url == "signed"
+        mock_helper.assert_called_once_with("file-id")
+
+
+def test_site_icon_url_is_none_for_non_image_icon():
+    site = SimpleNamespace(
+        title="Example",
+        chat_color_theme=None,
+        chat_color_theme_inverted=False,
+        icon_type=IconType.EMOJI,
+        icon="file-id",
+        icon_background=None,
+        description=None,
+        copyright=None,
+        privacy_policy=None,
+        custom_disclaimer=None,
+        default_language="en-US",
+        show_workflow_steps=True,
+        use_icon_as_answer_icon=False,
+    )
+
+    with patch("controllers.common.fields.file_helpers.get_signed_file_url") as mock_helper:
+        model = Site.model_validate(site)
+
+        assert model.icon_url is None
+        mock_helper.assert_not_called()