diff --git a/user_tools/src/spark_rapids_tools/cmdli/argprocessor.py b/user_tools/src/spark_rapids_tools/cmdli/argprocessor.py
index 978f683c1..87b39c40e 100644
--- a/user_tools/src/spark_rapids_tools/cmdli/argprocessor.py
+++ b/user_tools/src/spark_rapids_tools/cmdli/argprocessor.py
@@ -400,6 +400,15 @@ def init_extra_arg_cases(self) -> list:
     def define_invalid_arg_cases(self) -> None:
         super().define_invalid_arg_cases()
         self.define_rejected_missing_eventlogs()
+        self.rejected['Missing Platform argument'] = {
+            'valid': False,
+            'callable': partial(self.raise_validation_exception,
+                                'Cannot run tool cmd without platform argument. Re-run the command '
+                                'providing the platform argument.'),
+            'cases': [
+                [ArgValueCase.UNDEFINED, ArgValueCase.IGNORE, ArgValueCase.IGNORE]
+            ]
+        }
         self.rejected['Cluster By Name Without Platform Hints'] = {
             'valid': False,
             'callable': partial(self.raise_validation_exception,
diff --git a/user_tools/tests/spark_rapids_tools_ut/test_tool_argprocessor.py b/user_tools/tests/spark_rapids_tools_ut/test_tool_argprocessor.py
index 300751242..ff4bfff35 100644
--- a/user_tools/tests/spark_rapids_tools_ut/test_tool_argprocessor.py
+++ b/user_tools/tests/spark_rapids_tools_ut/test_tool_argprocessor.py
@@ -131,13 +131,9 @@ def test_with_platform_with_eventlogs(self, get_ut_data_dir, tool_name, csp):
                                 cost_savings_enabled=False,
                                 expected_platform=csp)
 
-        # should pass: platform not provided; event logs are provided
-        tool_args = self.create_tool_args_should_pass(tool_name,
-                                                      eventlogs=f'{get_ut_data_dir}/eventlogs')
-        # for qualification, cost savings should be disabled because cluster is not provided
-        self.validate_tool_args(tool_name=tool_name, tool_args=tool_args,
-                                cost_savings_enabled=False,
-                                expected_platform=CspEnv.ONPREM)
+        # should fail: platform must be provided
+        self.create_tool_args_should_fail(tool_name,
+                                          eventlogs=f'{get_ut_data_dir}/eventlogs')
 
     @pytest.mark.parametrize('tool_name', ['qualification', 'profiling'])
     @pytest.mark.parametrize('csp', all_csps)
@@ -150,17 +146,19 @@ def test_with_platform_with_eventlogs_with_jar_files(self, get_ut_data_dir, tool
                                                       tools_jar=f'{get_ut_data_dir}/tools_mock.jar')
         assert tool_args['toolsJar'] == f'{get_ut_data_dir}/tools_mock.jar'
 
-        # should pass: tools_jar is correct
-        tool_args = self.create_tool_args_should_pass(tool_name, eventlogs=f'{get_ut_data_dir}/eventlogs',
-                                                      tools_jar=f'{get_ut_data_dir}/tools_mock.jar')
-        assert tool_args['toolsJar'] == f'{get_ut_data_dir}/tools_mock.jar'
+        # should fail: platform must be provided
+        self.create_tool_args_should_fail(tool_name,
+                                          eventlogs=f'{get_ut_data_dir}/eventlogs',
+                                          tools_jar=f'{get_ut_data_dir}/tools_mock.jar')
 
         # should fail: tools_jar does not exist
-        self.create_tool_args_should_fail(tool_name, eventlogs=f'{get_ut_data_dir}/eventlogs',
+        self.create_tool_args_should_fail(tool_name,  platform=csp,
+                                          eventlogs=f'{get_ut_data_dir}/eventlogs',
                                           tools_jar=f'{get_ut_data_dir}/tools_mock.txt')
 
         # should fail: tools_jar is not .jar extension
-        self.create_tool_args_should_fail(tool_name, eventlogs=f'{get_ut_data_dir}/eventlogs',
+        self.create_tool_args_should_fail(tool_name,  platform=csp,
+                                          eventlogs=f'{get_ut_data_dir}/eventlogs',
                                           tools_jar=f'{get_ut_data_dir}/worker_info.yaml')
 
     @pytest.mark.parametrize('tool_name', ['qualification', 'profiling'])
@@ -230,25 +228,15 @@ def test_with_platform_with_cluster_props(self, get_ut_data_dir, tool_name, csp,
             self.validate_tool_args(tool_name=tool_name, tool_args=tool_args,
                                     cost_savings_enabled=True,
                                     expected_platform=csp)
-
-            # should pass: platform not provided; missing eventlogs should be accepted for all CSPs (except onPrem)
-            # because the eventlogs can be retrieved from the cluster properties
-            tool_args = self.create_tool_args_should_pass(tool_name,
-                                                          cluster=cluster_prop_file)
-            # for qualification, cost savings should be enabled because cluster is provided
-            self.validate_tool_args(tool_name=tool_name, tool_args=tool_args,
-                                    cost_savings_enabled=True,
-                                    expected_platform=csp)
         else:
             # should fail: onprem platform cannot retrieve eventlogs from cluster properties
             self.create_tool_args_should_fail(tool_name,
                                               platform=csp,
                                               cluster=cluster_prop_file)
 
-            # should fail: platform not provided; defaults platform to onprem, cannot retrieve eventlogs from
-            # cluster properties
-            self.create_tool_args_should_fail(tool_name,
-                                              cluster=cluster_prop_file)
+        # should fail: platform must be provided for all CSPs as well as onprem
+        self.create_tool_args_should_fail(tool_name,
+                                          cluster=cluster_prop_file)
 
     @pytest.mark.parametrize('tool_name', ['qualification', 'profiling'])
     @pytest.mark.parametrize('csp,prop_path', all_cpu_cluster_props)
@@ -266,14 +254,10 @@ def test_with_platform_with_cluster_props_with_eventlogs(self, get_ut_data_dir,
                                 cost_savings_enabled=CspEnv(csp) != CspEnv.ONPREM,
                                 expected_platform=csp)
 
-        # should pass: platform not provided; cluster properties and eventlogs are provided
-        tool_args = self.create_tool_args_should_pass(tool_name,
-                                                      cluster=cluster_prop_file,
-                                                      eventlogs=f'{get_ut_data_dir}/eventlogs')
-        # for qualification, cost savings should be enabled because cluster is provided (except for onprem)
-        self.validate_tool_args(tool_name=tool_name, tool_args=tool_args,
-                                cost_savings_enabled=CspEnv(csp) != CspEnv.ONPREM,
-                                expected_platform=csp)
+        # should fail: platform must be provided
+        self.create_tool_args_should_fail(tool_name,
+                                          cluster=cluster_prop_file,
+                                          eventlogs=f'{get_ut_data_dir}/eventlogs')
 
     @pytest.mark.parametrize('tool_name', ['profiling'])
     @pytest.mark.parametrize('csp', all_csps)
@@ -308,18 +292,15 @@ def test_with_platform_with_autotuner_with_eventlogs(self, get_ut_data_dir, tool
                                 cost_savings_enabled=False,
                                 expected_platform=csp)
 
-        # should pass: platform not provided; autotuner properties and eventlogs are provided
-        tool_args = self.create_tool_args_should_pass(tool_name,
-                                                      cluster=autotuner_prop_file,
-                                                      eventlogs=f'{get_ut_data_dir}/eventlogs')
-        # cost savings should be disabled for profiling
-        self.validate_tool_args(tool_name=tool_name, tool_args=tool_args,
-                                cost_savings_enabled=False,
-                                expected_platform=CspEnv.ONPREM)
+        # should fail: platform must be provided
+        self.create_tool_args_should_fail(tool_name,
+                                          cluster=autotuner_prop_file,
+                                          eventlogs=f'{get_ut_data_dir}/eventlogs')
 
     @pytest.mark.parametrize('prop_path', [autotuner_prop_path])
     def test_profiler_with_driverlog(self, get_ut_data_dir, prop_path):
         prof_args = AbsToolUserArgModel.create_tool_args('profiling',
+                                                         platform=CspEnv.get_default(),
                                                          driverlog=f'{get_ut_data_dir}/{prop_path}')
         assert not prof_args['requiresEventlogs']
         assert prof_args['rapidOptions']['driverlog'] == f'{get_ut_data_dir}/{prop_path}'