diff --git a/tests/unit/encoders/test_mistral.py b/tests/unit/encoders/test_mistral.py
index ec8ad8d10ea81791d4bec99c20c43a0e2e90e1c1..c2a91c128d22966da177dfc812e37d3bda215b09 100644
--- a/tests/unit/encoders/test_mistral.py
+++ b/tests/unit/encoders/test_mistral.py
@@ -29,13 +29,13 @@ class TestMistralEncoder:
         assert "Mistral client not initialized" in str(e.value)
 
     def test_mistralai_encoder_init_exception(self, mocker):
-        mocker.patch("mistralai.client.MistralClient", side_effect=Exception("Initialization error"))
+        mocker.patch(
+            "mistralai.client.MistralClient",
+            side_effect=Exception("Initialization error"),
+        )
         with pytest.raises(ValueError) as e:
             MistralEncoder()
-        assert (
-            "Mistral API key not provided"
-            in str(e.value)
-        )
+        assert "Mistral API key not provided" in str(e.value)
 
     def test_mistralai_encoder_call_success(self, mistralai_encoder, mocker):
         mock_embeddings = mocker.Mock()
@@ -90,7 +90,10 @@ class TestMistralEncoder:
         with pytest.raises(ValueError) as e:
             mistralai_encoder(["test document"])
 
-        assert "Unable to connect to MistralAI ('Non-MistralException',): Non-MistralException" in str(e.value)
+        assert (
+            "Unable to connect to MistralAI ('Non-MistralException',): Non-MistralException"
+            in str(e.value)
+        )
 
     def test_mistralai_encoder_call_successful_retry(self, mistralai_encoder, mocker):
         mock_embeddings = mocker.Mock()
diff --git a/tests/unit/llms/test_llm_mistral.py b/tests/unit/llms/test_llm_mistral.py
index 987fbb2484ef8749e139c6e215b3ce94d0a4eb6d..4e01ca5af528ea3d92b316c04b2fcf1f19f068c6 100644
--- a/tests/unit/llms/test_llm_mistral.py
+++ b/tests/unit/llms/test_llm_mistral.py
@@ -35,14 +35,12 @@ class TestMistralAILLM:
 
     def test_mistralai_llm_init_exception(self, mocker):
         mocker.patch(
-            "mistralai.client.MistralClient", side_effect=Exception("Initialization error")
+            "mistralai.client.MistralClient",
+            side_effect=Exception("Initialization error"),
         )
         with pytest.raises(ValueError) as e:
             MistralAILLM()
-        assert (
-            "MistralAI API key cannot be 'None'."
-            in str(e.value)
-        )
+        assert "MistralAI API key cannot be 'None'." in str(e.value)
 
     def test_mistralai_llm_call_success(self, mistralai_llm, mocker):
         mock_completion = mocker.MagicMock()