fix: fix function tool name parsing

to fix https://github.com/google/adk-python/issues/824

PiperOrigin-RevId: 761703269

tests/unittests/tools/test_function_tool.py

@@ -41,6 +41,10 @@ async def async_function_for_testing_with_2_arg_and_no_tool_context(arg1, arg2):
 
 class AsyncCallableWith2ArgsAndNoToolContext:
 
+  def __init__(self):
+    self.__name__ = "Async callable name"
+    self.__doc__ = "Async callable doc"
+
   async def __call__(self, arg1, arg2):
     assert arg1
     assert arg2
@@ -57,6 +61,7 @@ def function_for_testing_with_1_arg_and_tool_context(arg1, tool_context):
 class AsyncCallableWith1ArgAndToolContext:
 
   async def __call__(self, arg1, tool_context):
+    """Async call doc"""
     assert arg1
     assert tool_context
     return arg1
@@ -107,6 +112,8 @@ async def test_run_async_with_tool_context_async_callable():
   args = {"arg1": "test_value_1"}
   result = await tool.run_async(args=args, tool_context=MagicMock())
   assert result == "test_value_1"
+  assert tool.name == "AsyncCallableWith1ArgAndToolContext"
+  assert tool.description == "Async call doc"
 
 
 @pytest.mark.asyncio
@@ -125,6 +132,8 @@ async def test_run_async_without_tool_context_async_callable():
   args = {"arg1": "test_value_1", "arg2": "test_value_2"}
   result = await tool.run_async(args=args, tool_context=MagicMock())
   assert result == "test_value_1"
+  assert tool.name == "Async callable name"
+  assert tool.description == "Async callable doc"
 
 
 @pytest.mark.asyncio