diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 8dd6287..589e66d 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -5,11 +5,6 @@ repos:
     hooks:
       - id: ruff
         args: [--fix, --exit-non-zero-on-fix]
-  - repo: https://github.com/psf/black
-    rev: 22.3.0
-    hooks:
-    - id: black
-      language_version: python3
   - repo: https://github.com/pre-commit/pre-commit-hooks
     rev: v4.3.0
     hooks:
diff --git a/genai_impact/tracer.py b/genai_impact/tracer.py
index 39d3e82..662eb8b 100644
--- a/genai_impact/tracer.py
+++ b/genai_impact/tracer.py
@@ -15,7 +15,7 @@ def init_instruments() -> None:
 
 
 def init_openai_instrumentor() -> None:
-    if importlib.util.find_spec('openai') is not None:
+    if importlib.util.find_spec("openai") is not None:
         from genai_impact.tracers.openai_tracer import OpenAIInstrumentor
 
         instrumentor = OpenAIInstrumentor()
@@ -23,7 +23,7 @@ def init_openai_instrumentor() -> None:
 
 
 def init_anthropic_instrumentor() -> None:
-    if importlib.util.find_spec('anthropic') is not None:
+    if importlib.util.find_spec("anthropic") is not None:
         from genai_impact.tracers.anthropic_tracer import AnthropicInstrumentor
 
         instrumentor = AnthropicInstrumentor()
@@ -31,7 +31,7 @@ def init_anthropic_instrumentor() -> None:
 
 
 def init_mistralai_instrumentor() -> None:
-    if importlib.util.find_spec('mistralai') is not None:
+    if importlib.util.find_spec("mistralai") is not None:
         from genai_impact.tracers.mistralai_tracer import MistralAIInstrumentor
 
         instrumentor = MistralAIInstrumentor()
diff --git a/genai_impact/tracers/anthropic_tracer.py b/genai_impact/tracers/anthropic_tracer.py
index 37b6d66..6015846 100644
--- a/genai_impact/tracers/anthropic_tracer.py
+++ b/genai_impact/tracers/anthropic_tracer.py
@@ -4,7 +4,6 @@
 
 from genai_impact.compute_impacts import Impacts, compute_llm_impact
 
-
 try:
     from anthropic import Anthropic as _Anthropic
     from anthropic.types import Message as _Message
@@ -23,7 +22,7 @@ class Message(_Message):
     impacts: Impacts
 
 
-def _set_impacts(response):
+def _set_impacts(response: Message) -> Impacts:
     model_size = _MODEL_SIZES.get(response.model)
     output_tokens = response.usage.output_tokens
     impacts = compute_llm_impact(
@@ -41,7 +40,7 @@ def anthropic_chat_wrapper(
 
 
 class AnthropicInstrumentor:
-    def __init__(self):
+    def __init__(self) -> None:
         self.wrapped_methods = [
             {
                 "module": "anthropic.resources",
@@ -50,7 +49,7 @@ def __init__(self):
             },
         ]
 
-    def instrument(self):
+    def instrument(self) -> None:
         for wrapper in self.wrapped_methods:
             wrap_function_wrapper(
                 wrapper["module"],
diff --git a/genai_impact/tracers/mistralai_tracer.py b/genai_impact/tracers/mistralai_tracer.py
index a482dc4..7bdeac5 100644
--- a/genai_impact/tracers/mistralai_tracer.py
+++ b/genai_impact/tracers/mistralai_tracer.py
@@ -39,7 +39,7 @@ def mistralai_chat_wrapper(
 
 
 class MistralAIInstrumentor:
-    def __init__(self):
+    def __init__(self) -> None:
         self.wrapped_methods = [
             {
                 "module": "mistralai.client",
@@ -48,7 +48,7 @@ def __init__(self):
             },
         ]
 
-    def instrument(self):
+    def instrument(self) -> None:
         for wrapper in self.wrapped_methods:
             wrap_function_wrapper(
                 wrapper["module"],
diff --git a/genai_impact/tracers/openai_tracer.py b/genai_impact/tracers/openai_tracer.py
index 97c4352..4bb1b9c 100644
--- a/genai_impact/tracers/openai_tracer.py
+++ b/genai_impact/tracers/openai_tracer.py
@@ -44,7 +44,7 @@ def openai_chat_wrapper(
 
 
 class OpenAIInstrumentor:
-    def __init__(self):
+    def __init__(self) -> None:
         self.wrapped_methods = [
             {
                 "module": "openai.resources.chat.completions",
@@ -53,7 +53,7 @@ def __init__(self):
             },
         ]
 
-    def instrument(self):
+    def instrument(self) -> None:
         for wrapper in self.wrapped_methods:
             wrap_function_wrapper(
                 wrapper["module"],