Fix litellm flatten_messages_as_text detection

src/smolagents/models.py

@@ -22,7 +22,6 @@ import uuid
 from copy import deepcopy
 from dataclasses import asdict, dataclass
 from enum import Enum
-from functools import cached_property
 from typing import TYPE_CHECKING, Any, Dict, List, Optional, Union
 
 from huggingface_hub import InferenceClient
@@ -857,16 +856,11 @@ class LiteLLMModel(Model):
         self.api_base = api_base
         self.api_key = api_key
         self.custom_role_conversions = custom_role_conversions
-
-    @cached_property
-    def _flatten_messages_as_text(self):
-        import litellm
-
-        model_info: dict = litellm.get_model_info(self.model_id)
-        if model_info["litellm_provider"] == "ollama":
-            return model_info["key"] != "llava"
-
-        return False
+        self.flatten_messages_as_text = (
+            kwargs.get("flatten_messages_as_text")
+            if "flatten_messages_as_text" in kwargs
+            else self.model_id.startswith(("ollama", "groq", "cerebras"))
+        )
 
     def __call__(
         self,
@@ -887,7 +881,7 @@ class LiteLLMModel(Model):
             api_base=self.api_base,
             api_key=self.api_key,
             convert_images_to_image_urls=True,
-            flatten_messages_as_text=self._flatten_messages_as_text,
+            flatten_messages_as_text=self.flatten_messages_as_text,
             custom_role_conversions=self.custom_role_conversions,
             **kwargs,
         )

tests/test_models.py

@@ -23,7 +23,7 @@ from unittest.mock import MagicMock, patch
 import pytest
 from transformers.testing_utils import get_tests_dir
 
-from smolagents import ChatMessage, HfApiModel, MLXModel, TransformersModel, models, tool
+from smolagents import ChatMessage, HfApiModel, LiteLLMModel, MLXModel, TransformersModel, models, tool
 from smolagents.models import MessageRole, get_clean_message_list, parse_json_if_needed
 
 
@@ -50,18 +50,6 @@ class ModelTests(unittest.TestCase):
         data = json.loads(message.model_dump_json())
         assert data["content"] == [{"type": "text", "text": "Hello!"}]
 
-    @pytest.mark.skipif(not os.getenv("RUN_ALL"), reason="RUN_ALL environment variable not set")
-    def test_get_hfapi_message_no_tool(self):
-        model = HfApiModel(max_tokens=10)
-        messages = [{"role": "user", "content": [{"type": "text", "text": "Hello!"}]}]
-        model(messages, stop_sequences=["great"])
-
-    @pytest.mark.skipif(not os.getenv("RUN_ALL"), reason="RUN_ALL environment variable not set")
-    def test_get_hfapi_message_no_tool_external_provider(self):
-        model = HfApiModel(model="Qwen/Qwen2.5-Coder-32B-Instruct", provider="together", max_tokens=10)
-        messages = [{"role": "user", "content": [{"type": "text", "text": "Hello!"}]}]
-        model(messages, stop_sequences=["great"])
-
     @unittest.skipUnless(sys.platform.startswith("darwin"), "requires macOS")
     def test_get_mlx_message_no_tool(self):
         model = MLXModel(model_id="HuggingFaceTB/SmolLM2-135M-Instruct", max_tokens=10)
@@ -142,6 +130,43 @@ class TestHfApiModel:
             "role conversion should be applied"
         )
 
+    @pytest.mark.skipif(not os.getenv("RUN_ALL"), reason="RUN_ALL environment variable not set")
+    def test_get_hfapi_message_no_tool(self):
+        model = HfApiModel(max_tokens=10)
+        messages = [{"role": "user", "content": [{"type": "text", "text": "Hello!"}]}]
+        model(messages, stop_sequences=["great"])
+
+    @pytest.mark.skipif(not os.getenv("RUN_ALL"), reason="RUN_ALL environment variable not set")
+    def test_get_hfapi_message_no_tool_external_provider(self):
+        model = HfApiModel(model="Qwen/Qwen2.5-Coder-32B-Instruct", provider="together", max_tokens=10)
+        messages = [{"role": "user", "content": [{"type": "text", "text": "Hello!"}]}]
+        model(messages, stop_sequences=["great"])
+
+
+class TestLiteLLMModel:
+    @pytest.mark.parametrize(
+        "model_id, error_flag",
+        [
+            ("groq/llama-3.3-70b", "Missing API Key"),
+            ("cerebras/llama-3.3-70b", "Wrong API Key"),
+            ("ollama/llama2", "not found"),
+        ],
+    )
+    def test_call_different_providers_without_key(self, model_id, error_flag):
+        model = LiteLLMModel(model_id=model_id)
+        messages = [{"role": "user", "content": [{"type": "text", "text": "Test message"}]}]
+        with pytest.raises(Exception) as e:
+            # This should raise 401 error because of missing API key, not fail for any "bad format" reason
+            model(messages)
+        assert error_flag in str(e)
+
+    def test_passing_flatten_messages(self):
+        model = LiteLLMModel(model_id="groq/llama-3.3-70b", flatten_messages_as_text=False)
+        assert not model.flatten_messages_as_text
+
+        model = LiteLLMModel(model_id="fal/llama-3.3-70b", flatten_messages_as_text=True)
+        assert model.flatten_messages_as_text
+
 
 def test_get_clean_message_list_basic():
     messages = [