diff --git a/genai_impact/exceptions.py b/genai_impact/exceptions.py
index 567eac0..689c8f0 100644
--- a/genai_impact/exceptions.py
+++ b/genai_impact/exceptions.py
@@ -1,6 +1,7 @@
 class GenAIImpactError(Exception):
     pass
 
+
 class TracerInitializationError(GenAIImpactError):
-    "Tracer is initialized twice"
+    """Tracer is initialized twice"""
     pass
diff --git a/genai_impact/tracer.py b/genai_impact/tracer.py
index 3cf3070..7f56bcc 100644
--- a/genai_impact/tracer.py
+++ b/genai_impact/tracer.py
@@ -19,6 +19,7 @@ def init_instruments() -> None:
     init_anthropic_instrumentor()
     init_mistralai_instrumentor()
 
+
 def init_openai_instrumentor() -> None:
     if importlib.util.find_spec("openai") is not None:
         from genai_impact.tracers.openai_tracer import OpenAIInstrumentor
@@ -26,6 +27,7 @@ def init_openai_instrumentor() -> None:
         instrumentor = OpenAIInstrumentor()
         instrumentor.instrument()
 
+
 def init_anthropic_instrumentor() -> None:
     if importlib.util.find_spec("anthropic") is not None:
         from genai_impact.tracers.anthropic_tracer import AnthropicInstrumentor
@@ -33,6 +35,7 @@ def init_anthropic_instrumentor() -> None:
         instrumentor = AnthropicInstrumentor()
         instrumentor.instrument()
 
+
 def init_mistralai_instrumentor() -> None:
     if importlib.util.find_spec("mistralai") is not None:
         from genai_impact.tracers.mistralai_tracer import MistralAIInstrumentor
diff --git a/genai_impact/tracers/mistralai_tracer.py b/genai_impact/tracers/mistralai_tracer.py
index a930883..f48bc16 100644
--- a/genai_impact/tracers/mistralai_tracer.py
+++ b/genai_impact/tracers/mistralai_tracer.py
@@ -44,7 +44,7 @@ def mistralai_chat_wrapper(
 
 async def mistralai_async_chat_wrapper(
     wrapped: Callable,
-    instance: _MistralAsyncClient, # noqa: ARG001
+    instance: _MistralAsyncClient,  # noqa: ARG001
     args: Any,
     kwargs: Any,
 ) -> ChatCompletionResponse:
diff --git a/genai_impact/tracers/openai_tracer.py b/genai_impact/tracers/openai_tracer.py
index dbc5b15..93b0bf9 100644
--- a/genai_impact/tracers/openai_tracer.py
+++ b/genai_impact/tracers/openai_tracer.py
@@ -25,12 +25,14 @@ def compute_impacts_and_return_response(response: Any) -> ChatCompletion:
     )
     return ChatCompletion(**response.model_dump(), impacts=impacts)
 
+
 def openai_chat_wrapper(
     wrapped: Callable, instance: Completions, args: Any, kwargs: Any  # noqa: ARG001
 ) -> ChatCompletion:
     response = wrapped(*args, **kwargs)
     return compute_impacts_and_return_response(response)
 
+
 async def openai_async_chat_wrapper(
     wrapped: Callable,
     instance: AsyncCompletions, # noqa: ARG001
@@ -41,7 +43,6 @@ async def openai_async_chat_wrapper(
     return compute_impacts_and_return_response(response)
 
 
-
 class OpenAIInstrumentor:
     def __init__(self) -> None:
         self.wrapped_methods = [
diff --git a/tests/test_tracer.py b/tests/test_tracer.py
index 2dcc6c9..7a0a5e8 100644
--- a/tests/test_tracer.py
+++ b/tests/test_tracer.py
@@ -2,6 +2,7 @@
 from genai_impact import Tracer
 from genai_impact.exceptions import GenAIImpactError
 
+
 def test_double_init(tracer_init):
     with pytest.raises(GenAIImpactError) as e:  
-        Tracer.init() # Second initialization
+        Tracer.init()   # Second initialization