diff --git a/google/genai/_mcp_utils.py b/google/genai/_mcp_utils.py
index 6cd632252..59fc36310 100644
--- a/google/genai/_mcp_utils.py
+++ b/google/genai/_mcp_utils.py
@@ -42,11 +42,7 @@ def mcp_to_gemini_tool(tool: McpTool) -> types.Tool:
       function_declarations=[{
           "name": tool.name,
           "description": tool.description,
-          "parameters": types.Schema.from_json_schema(
-              json_schema=types.JSONSchema(
-                  **_filter_to_supported_schema(tool.inputSchema)
-              )
-          ),
+          "parameters_json_schema": tool.inputSchema,
       }]
   )
 
diff --git a/google/genai/tests/live/test_live.py b/google/genai/tests/live/test_live.py
index 9ffebb726..b9082144e 100644
--- a/google/genai/tests/live/test_live.py
+++ b/google/genai/tests/live/test_live.py
@@ -1141,11 +1141,11 @@ async def test_bidi_setup_to_api_with_config_mcp_tools(
           'model': 'models/test_model',
           'tools': [{
               'functionDeclarations': [{
-                  'parameters': {
-                      'type': 'OBJECT',
+                  'parametersJsonSchema': {
+                      'type': 'object',
                       'properties': {
                           'location': {
-                              'type': 'STRING',
+                              'type': 'string',
                           },
                       },
                   },
@@ -1167,11 +1167,11 @@ async def test_bidi_setup_to_api_with_config_mcp_tools(
           ),
           'tools': [{
               'functionDeclarations': [{
-                  'parameters': {
-                      'type': 'OBJECT',
+                  'parametersJsonSchema': {
+                      'type': 'object',
                       'properties': {
                           'location': {
-                              'type': 'STRING',
+                              'type': 'string',
                           },
                       },
                   },
@@ -1197,6 +1197,10 @@ async def test_bidi_setup_to_api_with_config_mcp_tools(
           ],
       },
   )
+  
+  print(result, 'hello result!!')
+  print(expected_result_vertexai, 'hello expected_result_vertexai!!')
+  print(expected_result_googleai, 'hello expected_result_googleai!!')
 
   assert (
       result == expected_result_vertexai
@@ -1238,11 +1242,11 @@ async def list_tools(self):
           'model': 'models/test_model',
           'tools': [{
               'functionDeclarations': [{
-                  'parameters': {
-                      'type': 'OBJECT',
+                  'parametersJsonSchema': {
+                      'type': 'object',
                       'properties': {
                           'location': {
-                              'type': 'STRING',
+                              'type': 'string',
                           },
                       },
                   },
@@ -1264,11 +1268,11 @@ async def list_tools(self):
           ),
           'tools': [{
               'functionDeclarations': [{
-                  'parameters': {
-                      'type': 'OBJECT',
+                  'parametersJsonSchema': {
+                      'type': 'object',
                       'properties': {
                           'location': {
-                              'type': 'STRING',
+                              'type': 'string',
                           },
                       },
                   },
diff --git a/google/genai/tests/mcp/test_mcp_to_gemini_tools.py b/google/genai/tests/mcp/test_mcp_to_gemini_tools.py
index 62db7d89a..bf20f9aba 100644
--- a/google/genai/tests/mcp/test_mcp_to_gemini_tools.py
+++ b/google/genai/tests/mcp/test_mcp_to_gemini_tools.py
@@ -39,16 +39,17 @@ def test_empty_mcp_tools_list():
 
 def test_unknown_field_conversion():
   """Test conversion of MCP tools with unknown fields to Gemini tools."""
+  inputSchema = {
+      'type': 'object',
+      'properties': {},
+      'unknown_field': 'unknownField',
+      'unknown_object': {},
+  }
   mcp_tools = [
       mcp_types.Tool(
           name='tool',
           description='tool-description',
-          inputSchema={
-              'type': 'object',
-              'properties': {},
-              'unknown_field': 'unknownField',
-              'unknown_object': {},
-          },
+          inputSchema=inputSchema,
       ),
   ]
   result = _mcp_utils.mcp_to_gemini_tools(mcp_tools)
@@ -58,10 +59,7 @@ def test_unknown_field_conversion():
               types.FunctionDeclaration(
                   name='tool',
                   description='tool-description',
-                  parameters=types.Schema(
-                      type='OBJECT',
-                      properties={},
-                  ),
+                  parameters_json_schema=inputSchema,
               ),
           ],
       ),
@@ -70,24 +68,25 @@ def test_unknown_field_conversion():
 
 def test_items_conversion():
   """Test conversion of MCP tools with items to Gemini tools."""
+  inputSchema = {
+      'type': 'array',
+      'items': {
+          'type': 'object',
+          'properties': {
+              'key1': {
+                  'type': 'string',
+              },
+              'key2': {
+                  'type': 'number',
+              },
+          },
+      },
+  }
   mcp_tools = [
       mcp_types.Tool(
           name='tool',
           description='tool-description',
-          inputSchema={
-              'type': 'array',
-              'items': {
-                  'type': 'object',
-                  'properties': {
-                      'key1': {
-                          'type': 'string',
-                      },
-                      'key2': {
-                          'type': 'number',
-                      },
-                  },
-              },
-          },
+          inputSchema=inputSchema,
       ),
   ]
   result = _mcp_utils.mcp_to_gemini_tools(mcp_tools)
@@ -97,16 +96,7 @@ def test_items_conversion():
               types.FunctionDeclaration(
                   name='tool',
                   description='tool-description',
-                  parameters=types.Schema(
-                      type='ARRAY',
-                      items=types.Schema(
-                          type='OBJECT',
-                          properties={
-                              'key1': types.Schema(type='STRING'),
-                              'key2': types.Schema(type='NUMBER'),
-                          },
-                      ),
-                  ),
+                  parameters_json_schema=inputSchema,
               ),
           ],
       ),
@@ -115,21 +105,24 @@ def test_items_conversion():
 
 def test_any_of_conversion():
   """Test conversion of MCP tools with any_of to Gemini tools."""
+  
+  inputSchema = {
+      'type': 'object',
+      'any_of': [
+          {
+              'type': 'string',
+          },
+          {
+              'type': 'number',
+          },
+      ],
+  }
+
   mcp_tools = [
       mcp_types.Tool(
           name='tool',
           description='tool-description',
-          inputSchema={
-              'type': 'object',
-              'any_of': [
-                  {
-                      'type': 'string',
-                  },
-                  {
-                      'type': 'number',
-                  },
-              ],
-          },
+          inputSchema=inputSchema,
       ),
   ]
   result = _mcp_utils.mcp_to_gemini_tools(mcp_tools)
@@ -139,13 +132,7 @@ def test_any_of_conversion():
               types.FunctionDeclaration(
                   name='tool',
                   description='tool-description',
-                  parameters=types.Schema(
-                      type='OBJECT',
-                      any_of=[
-                          types.Schema(type='STRING'),
-                          types.Schema(type='NUMBER'),
-                      ],
-                  ),
+                  parameters_json_schema=inputSchema,
               ),
           ],
       ),
@@ -154,21 +141,22 @@ def test_any_of_conversion():
 
 def test_properties_conversion():
   """Test conversion of MCP tools with properties to Gemini tools."""
+  inputSchema = {
+      'type': 'object',
+      'properties': {
+          'key1': {
+              'type': 'string',
+          },
+          'key2': {
+              'type': 'number',
+          },
+      },
+  }
   mcp_tools = [
       mcp_types.Tool(
           name='tool',
           description='tool-description',
-          inputSchema={
-              'type': 'object',
-              'properties': {
-                  'key1': {
-                      'type': 'string',
-                  },
-                  'key2': {
-                      'type': 'number',
-                  },
-              },
-          },
+          inputSchema=inputSchema,
       ),
   ]
   result = _mcp_utils.mcp_to_gemini_tools(mcp_tools)
@@ -178,13 +166,7 @@ def test_properties_conversion():
               types.FunctionDeclaration(
                   name='tool',
                   description='tool-description',
-                  parameters=types.Schema(
-                      type='OBJECT',
-                      properties={
-                          'key1': types.Schema(type='STRING'),
-                          'key2': types.Schema(type='NUMBER'),
-                      },
-                  ),
+                  parameters_json_schema=inputSchema,
               ),
           ],
       ),
diff --git a/google/genai/tests/transformers/test_t_tool.py b/google/genai/tests/transformers/test_t_tool.py
index 32d86221b..d9a5fcd4f 100644
--- a/google/genai/tests/transformers/test_t_tool.py
+++ b/google/genai/tests/transformers/test_t_tool.py
@@ -105,33 +105,29 @@ def test_mcp_tool(client):
   if not _is_mcp_imported:
     return
 
+  inputSchema = {
+      'type': 'object',
+      'properties': {
+          'key1': {
+              'type': 'string',
+          },
+          'key2': {
+              'type': 'number',
+          },
+      },
+  }
+
   mcp_tool = mcp_types.Tool(
       name='tool',
       description='tool-description',
-      inputSchema={
-          'type': 'object',
-          'properties': {
-              'key1': {
-                  'type': 'string',
-              },
-              'key2': {
-                  'type': 'number',
-              },
-          },
-      },
+      inputSchema=inputSchema,
   )
   assert t.t_tool(client, mcp_tool) == types.Tool(
       function_declarations=[
           types.FunctionDeclaration(
               name='tool',
               description='tool-description',
-              parameters=types.Schema(
-                  type='OBJECT',
-                  properties={
-                      'key1': types.Schema(type='STRING'),
-                      'key2': types.Schema(type='NUMBER'),
-                  },
-              ),
+              parameters_json_schema=inputSchema,
           )
       ]
   )
diff --git a/google/genai/tests/transformers/test_t_tools.py b/google/genai/tests/transformers/test_t_tools.py
index 05d8ce263..bcda36d01 100644
--- a/google/genai/tests/transformers/test_t_tools.py
+++ b/google/genai/tests/transformers/test_t_tools.py
@@ -104,20 +104,22 @@ def test_mcp_tool(client):
   if not _is_mcp_imported:
     return
 
+  inputSchema = {
+      'type': 'object',
+      'properties': {
+          'key1': {
+              'type': 'string',
+          },
+          'key2': {
+              'type': 'number',
+          },
+      },
+  }
+
   mcp_tool = mcp_types.Tool(
       name='tool',
       description='tool-description',
-      inputSchema={
-          'type': 'object',
-          'properties': {
-              'key1': {
-                  'type': 'string',
-              },
-              'key2': {
-                  'type': 'number',
-              },
-          },
-      },
+      inputSchema=inputSchema,
   )
   assert t.t_tools(client, [mcp_tool]) == [
       types.Tool(
@@ -125,13 +127,7 @@ def test_mcp_tool(client):
               types.FunctionDeclaration(
                   name='tool',
                   description='tool-description',
-                  parameters=types.Schema(
-                      type='OBJECT',
-                      properties={
-                          'key1': types.Schema(type='STRING'),
-                          'key2': types.Schema(type='NUMBER'),
-                      },
-                  ),
+                  parameters_json_schema=inputSchema,
               )
           ]
       )
@@ -143,29 +139,32 @@ def test_multiple_tools(client):
   if not _is_mcp_imported:
     return
 
+  inputSchema1 = {
+      'type': 'object',
+      'properties': {
+          'key1': {
+              'type': 'string',
+          },
+      },
+  }
+  inputSchema2 = {
+      'type': 'object',
+      'properties': {
+          'key1': {
+              'type': 'number',
+          },
+      },
+  }
+
   mcp_tool1 = mcp_types.Tool(
       name='tool1',
       description='tool1-description',
-      inputSchema={
-          'type': 'object',
-          'properties': {
-              'key1': {
-                  'type': 'string',
-              },
-          },
-      },
+      inputSchema=inputSchema1,
   )
   mcp_tool2 = mcp_types.Tool(
       name='tool2',
       description='tool2-description',
-      inputSchema={
-          'type': 'object',
-          'properties': {
-              'key1': {
-                  'type': 'number',
-              },
-          },
-      },
+      inputSchema=inputSchema2,
   )
   assert t.t_tools(client, [mcp_tool1, mcp_tool2]) == [
       types.Tool(
@@ -173,22 +172,12 @@ def test_multiple_tools(client):
               types.FunctionDeclaration(
                   name='tool1',
                   description='tool1-description',
-                  parameters=types.Schema(
-                      type='OBJECT',
-                      properties={
-                          'key1': types.Schema(type='STRING'),
-                      },
-                  ),
+                  parameters_json_schema=inputSchema1,
               ),
               types.FunctionDeclaration(
                   name='tool2',
                   description='tool2-description',
-                  parameters=types.Schema(
-                      type='OBJECT',
-                      properties={
-                          'key1': types.Schema(type='NUMBER'),
-                      },
-                  ),
+                  parameters_json_schema=inputSchema2,
               ),
           ]
       ),