Add type assertions for TextContent in tests

Author: wreed4

tests/client/test_sampling_callback.py

@@ -89,6 +89,7 @@ async def sampling_callback(
         params: CreateMessageRequestParams,
     ) -> CreateMessageResult:
         # Extract delay from the message content (e.g., "delay_0.3")
+        assert isinstance(params.messages[0].content, TextContent)
         message_text = params.messages[0].content.text
         if message_text.startswith("delay_"):
             delay = float(message_text.split("_")[1])

tests/shared/test_session.py

@@ -250,6 +250,7 @@ async def handle_list_tools() -> list[types.Tool]:
         )
 
         # Verify the request completed successfully
+        assert isinstance(result.content[0], TextContent)
         assert result.content[0].text == "Waited 0.1s"
         assert len(completion_order) == 1
         assert completion_order[0] == 0.1