diff --git a/python/semantic_kernel/connectors/ai/azure_ai_inference/services/utils.py b/python/semantic_kernel/connectors/ai/azure_ai_inference/services/utils.py
index 102f796c6030..7ad38b52af88 100644
--- a/python/semantic_kernel/connectors/ai/azure_ai_inference/services/utils.py
+++ b/python/semantic_kernel/connectors/ai/azure_ai_inference/services/utils.py
@@ -134,6 +134,9 @@ def _format_tool_message(message: ChatMessageContent) -> ToolMessage:
     Returns:
         The formatted tool message.
     """
+    if len(message.items) == 0:
+        raise ValueError("Tool message has no items; expected exactly one FunctionResultContent item.")
+
     if len(message.items) != 1:
         logger.warning(
             "Unsupported number of items in Tool message while formatting chat history for Azure AI"