fixing the standard integration tests in PR-491

credit for the original fix goes to SYED-M-HUSSAIN

Author: SYED-M-HUSSAIN

libs/aws/langchain_aws/chat_models/bedrock_converse.py

@@ -1170,9 +1170,9 @@ def _parse_stream_event(event: Dict[str, Any]) -> Optional[BaseMessageChunk]:
     if "messageStart" in event:
         # TODO: needed?
         return (
-            AIMessageChunk(content="")
+            AIMessageChunk(content=[])
             if event["messageStart"]["role"] == "assistant"
-            else HumanMessageChunk(content="")
+            else HumanMessageChunk(content=[])
         )
     elif "contentBlockStart" in event:
         block = {
@@ -1189,8 +1189,13 @@ def _parse_stream_event(event: Dict[str, Any]) -> Optional[BaseMessageChunk]:
                     index=event["contentBlockStart"]["contentBlockIndex"],
                 )
             )
-        # Keep content as list during streaming to preserve merging compatibility
-        content = [block]
+        if block["type"] == "tool_use":
+            # Keep tool calls as list to preserve type information
+            content = [block]
+        else:
+            # Keep content as list during streaming to preserve merging compatibility
+            content = [block]
+        
         return AIMessageChunk(content=content, tool_call_chunks=tool_call_chunks)
     elif "contentBlockDelta" in event:
         block = {
@@ -1207,12 +1212,17 @@ def _parse_stream_event(event: Dict[str, Any]) -> Optional[BaseMessageChunk]:
                     index=event["contentBlockDelta"]["contentBlockIndex"],
                 )
             )
-        # Keep content as list during streaming to preserve merging compatibility
-        content = [block]
+        if block["type"] == "tool_use":
+            # Keep tool calls as list to preserve type information
+            content = [block]
+        else:
+            # Keep content as list during streaming to preserve merging compatibility
+            content = [block]
+        
         return AIMessageChunk(content=content, tool_call_chunks=tool_call_chunks)
     elif "contentBlockStop" in event:
         # TODO: needed?
-        return AIMessageChunk(content="")
+        return AIMessageChunk(content=[])
     elif "messageStop" in event:
         # TODO: snake case response metadata?
         return AIMessageChunk(content="", response_metadata=event["messageStop"])

libs/aws/tests/integration_tests/chat_models/test_bedrock_converse.py

@@ -455,7 +455,7 @@ def test_structured_output_thinking_force_tool_use() -> None:
         },
     }
     with pytest.raises(llm.client.exceptions.ValidationException):
-        response = llm.client.converse(messages=messages, **params)
+        llm.client.converse(messages=messages, **params)
 
 
 def test_bedrock_pdf_inputs() -> None: