Fix: Exclude mirostat parameter when disabled in Ollama component

src/backend/tests/unit/components/languagemodels/test_chatollama_component.py

@@ -55,7 +55,7 @@ async def test_build_model(self, mock_chat_ollama, component_class, default_kwar
         mock_chat_ollama.assert_called_once_with(
             base_url="http://localhost:11434",
             model="ollama-model",
-            mirostat=0,
+            # mirostat is not included when disabled (set to None and filtered out)
             format="json",
             metadata={"keywords": ["model", "llm", "language model", "large language model"]},
             num_ctx=2048,
@@ -83,6 +83,51 @@ async def test_build_model_missing_base_url(self, mock_chat_ollama, component_cl
         with pytest.raises(ValueError, match=re.escape("Unable to connect to the Ollama API.")):
             component.build_model()
 
+    @patch("lfx.components.ollama.ollama.ChatOllama")
+    async def test_build_model_with_mirostat_enabled(self, mock_chat_ollama, component_class):
+        """Test that mirostat parameters are included when Mirostat is enabled."""
+        mock_instance = MagicMock()
+        mock_chat_ollama.return_value = mock_instance
+
+        component = component_class(
+            base_url="http://localhost:11434",
+            model_name="ollama-model",
+            mirostat="Mirostat",  # Setting to Mirostat (value 1)
+            mirostat_eta=0.1,
+            mirostat_tau=5.0,
+            temperature=0.1,
+        )
+        model = component.build_model()
+
+        # Verify that mirostat and its related params ARE passed
+        call_kwargs = mock_chat_ollama.call_args[1]
+        assert call_kwargs["mirostat"] == 1
+        assert call_kwargs["mirostat_eta"] == 0.1
+        assert call_kwargs["mirostat_tau"] == 5.0
+        assert model == mock_instance
+
+    @patch("lfx.components.ollama.ollama.ChatOllama")
+    async def test_build_model_with_mirostat_2_enabled(self, mock_chat_ollama, component_class):
+        """Test that mirostat parameters are included when Mirostat 2.0 is enabled."""
+        mock_instance = MagicMock()
+        mock_chat_ollama.return_value = mock_instance
+
+        component = component_class(
+            base_url="http://localhost:11434",
+            model_name="ollama-model",
+            mirostat="Mirostat 2.0",  # Setting to Mirostat 2.0 (value 2)
+            mirostat_eta=0.2,
+            mirostat_tau=10.0,
+            temperature=0.1,
+        )
+        model = component.build_model()
+        # Verify that mirostat and its related params ARE passed
+        call_kwargs = mock_chat_ollama.call_args[1]
+        assert call_kwargs["mirostat"] == 2
+        assert call_kwargs["mirostat_eta"] == 0.2
+        assert call_kwargs["mirostat_tau"] == 10.0
+        assert model == mock_instance
+
     @pytest.mark.asyncio
     @patch("lfx.components.ollama.ollama.httpx.AsyncClient.post")
     @patch("lfx.components.ollama.ollama.httpx.AsyncClient.get")

src/lfx/src/lfx/components/ollama/ollama.py

@@ -145,11 +145,11 @@ def build_model(self) -> LanguageModel:  # type: ignore[type-var]
         # Mapping mirostat settings to their corresponding values
         mirostat_options = {"Mirostat": 1, "Mirostat 2.0": 2}
 
-        # Default to 0 for 'Disabled'
-        mirostat_value = mirostat_options.get(self.mirostat, 0)
+        # Default to None for 'Disabled'
+        mirostat_value = mirostat_options.get(self.mirostat, None)
 
         # Set mirostat_eta and mirostat_tau to None if mirostat is disabled
-        if mirostat_value == 0:
+        if mirostat_value is None:
             mirostat_eta = None
             mirostat_tau = None
         else: