fix(litellm): add validation for stream parameter in LiteLLM (#1183)

Author: dbschmigelski

src/strands/models/litellm.py

@@ -272,6 +272,8 @@ async def stream(
 
         logger.debug("invoking model")
         try:
+            if kwargs.get("stream") is False:
+                raise ValueError("stream parameter cannot be explicitly set to False")
             response = await litellm.acompletion(**self.client_args, **request)
         except ContextWindowExceededError as e:
             logger.warning("litellm client raised context window overflow")

tests/strands/models/test_litellm.py

@@ -408,6 +408,16 @@ async def test_context_window_maps_to_typed_exception(litellm_acompletion, model
             pass
 
 
+@pytest.mark.asyncio
+async def test_stream_raises_error_when_stream_is_false(model):
+    """Test that stream raises ValueError when stream parameter is explicitly False."""
+    messages = [{"role": "user", "content": [{"text": "test"}]}]
+
+    with pytest.raises(ValueError, match="stream parameter cannot be explicitly set to False"):
+        async for _ in model.stream(messages, stream=False):
+            pass
+
+
 def test_format_request_messages_with_system_prompt_content():
     """Test format_request_messages with system_prompt_content parameter."""
     messages = [{"role": "user", "content": [{"text": "Hello"}]}]