diff --git a/src/nutrient_dws/api/direct.py b/src/nutrient_dws/api/direct.py
index 5f3b06b..690289c 100644
--- a/src/nutrient_dws/api/direct.py
+++ b/src/nutrient_dws/api/direct.py
@@ -478,7 +478,8 @@ def optimize_pdf(
             grayscale_annotations: Convert annotations to grayscale (default: False).
             disable_images: Remove all images from the PDF (default: False).
             mrc_compression: MCR compression (default: False).
-            image_optimization_quality: Image optimization quality from 1 (least optimized) to 4 (most optimized) (default: 2).
+            image_optimization_quality: Image optimization quality from 1 (least optimized)
+             to 4 (most optimized) (default: 2).
             linearize: Linearize (optimize for web viewing) the PDF (default: False).
 
         Returns:
@@ -487,7 +488,8 @@ def optimize_pdf(
         Raises:
             AuthenticationError: If API key is missing or invalid.
             APIError: For other API errors.
-            ValueError: If image_optimization_quality is not between 1-4 or no optimization is enabled
+            ValueError: If image_optimization_quality is not between 1-4
+            or no optimization is enabled
 
         Example:
             # Aggressive optimization for minimum file size
@@ -709,7 +711,11 @@ def split_pdf(
                 output_paths=["part1.pdf", "part2.pdf"]
             )
         """
-        from nutrient_dws.file_handler import prepare_file_for_upload, save_file_output, get_pdf_page_count
+        from nutrient_dws.file_handler import (
+            get_pdf_page_count,
+            prepare_file_for_upload,
+            save_file_output,
+        )
 
         # Validate inputs
         if not page_ranges:
@@ -731,15 +737,21 @@ def split_pdf(
 
             # Validate start is within document bounds
             if start < 0 or start >= num_of_pages:
-                raise ValueError(f"Page range {i}: start index {start} is out of bounds (0-{num_of_pages-1})")
+                raise ValueError(
+                    f"Page range {i}: start index {start} is out of bounds (0-{num_of_pages - 1})"
+                )
 
             # If end is specified, validate it's within document bounds
             if "end" in page_range:
                 end = page_range["end"]
                 if end < 0 or end >= num_of_pages:
-                    raise ValueError(f"Page range {i}: end index {end} is out of bounds (0-{num_of_pages-1})")
+                    raise ValueError(
+                        f"Page range {i}: end index {end} is out of bounds (0-{num_of_pages - 1})"
+                    )
                 if end < start:
-                    raise ValueError(f"Page range {i}: end index {end} cannot be less than start index {start}")
+                    raise ValueError(
+                        f"Page range {i}: end index {end} cannot be less than start index {start}"
+                    )
 
         results = []
 
@@ -814,7 +826,11 @@ def duplicate_pdf_pages(
                 output_path="reordered.pdf"
             )
         """
-        from nutrient_dws.file_handler import prepare_file_for_upload, save_file_output, get_pdf_page_count
+        from nutrient_dws.file_handler import (
+            get_pdf_page_count,
+            prepare_file_for_upload,
+            save_file_output,
+        )
 
         # Validate inputs
         if not page_indexes:
@@ -837,7 +853,9 @@ def duplicate_pdf_pages(
             else:
                 # Validate positive indexes are within bounds
                 if page_index >= num_of_pages:
-                    raise ValueError(f"Page index {page_index} is out of bounds (0-{num_of_pages-1})")
+                    raise ValueError(
+                        f"Page index {page_index} is out of bounds (0-{num_of_pages - 1})"
+                    )
                 # For positive indexes, create single-page range
                 parts.append({"file": "file", "pages": {"start": page_index, "end": page_index}})
 
@@ -905,7 +923,11 @@ def delete_pdf_pages(
                 output_path="pages_deleted.pdf"
             )
         """
-        from nutrient_dws.file_handler import prepare_file_for_upload, save_file_output, get_pdf_page_count
+        from nutrient_dws.file_handler import (
+            get_pdf_page_count,
+            prepare_file_for_upload,
+            save_file_output,
+        )
 
         # Validate inputs
         if not page_indexes:
@@ -924,7 +946,7 @@ def delete_pdf_pages(
         # Validate page indexes are within bounds
         for idx in page_indexes:
             if idx >= num_of_pages:
-                raise ValueError(f"Page index {idx} is out of bounds (0-{num_of_pages-1})")
+                raise ValueError(f"Page index {idx} is out of bounds (0-{num_of_pages - 1})")
 
         # Prepare file for upload
         file_field, file_data = prepare_file_for_upload(input_file, "file")
@@ -952,7 +974,9 @@ def delete_pdf_pages(
 
         # Add remaining pages after the last deleted page
         num_of_pages = get_pdf_page_count(input_file)
-        if (current_page > 0 or (current_page == 0 and len(sorted_indexes) == 0)) and current_page < num_of_pages:
+        if (
+            current_page > 0 or (current_page == 0 and len(sorted_indexes) == 0)
+        ) and current_page < num_of_pages:
             # Add all remaining pages from current_page onwards
             parts.append({"file": "file", "pages": {"start": current_page}})
 
@@ -1098,7 +1122,11 @@ def add_page(
                 output_path="with_blank_pages.pdf"
             )
         """
-        from nutrient_dws.file_handler import prepare_file_for_upload, save_file_output, get_pdf_page_count
+        from nutrient_dws.file_handler import (
+            get_pdf_page_count,
+            prepare_file_for_upload,
+            save_file_output,
+        )
 
         # Validate inputs
         if page_count < 1:
@@ -1394,7 +1422,11 @@ def set_page_label(
                 labels=[{"pages": {"start": 0, "end": 0}, "label": "Cover Page"}]
             )
         """
-        from nutrient_dws.file_handler import prepare_file_for_upload, save_file_output, get_pdf_page_count
+        from nutrient_dws.file_handler import (
+            get_pdf_page_count,
+            prepare_file_for_upload,
+            save_file_output,
+        )
 
         # Validate inputs
         if not labels:
@@ -1422,7 +1454,10 @@ def set_page_label(
             # Validate start is within document bounds
             start = pages["start"]
             if start < 0 or start >= num_of_pages:
-                raise ValueError(f"Label configuration {i}: start index {start} is out of bounds (0-{num_of_pages-1})")
+                raise ValueError(
+                    f"Label configuration {i}: start index {start}"
+                    f" is out of bounds (0-{num_of_pages - 1})"
+                )
 
             # Normalize pages - only include 'end' if explicitly provided
             normalized_pages = {"start": start}
@@ -1430,10 +1465,16 @@ def set_page_label(
                 end = pages["end"]
                 # Validate end is within document bounds
                 if end < 0 or end >= num_of_pages:
-                    raise ValueError(f"Label configuration {i}: end index {end} is out of bounds (0-{num_of_pages-1})")
+                    raise ValueError(
+                        f"Label configuration {i}: end index {end}"
+                        f" is out of bounds (0-{num_of_pages - 1})"
+                    )
                 # Validate end is not less than start
                 if end < start:
-                    raise ValueError(f"Label configuration {i}: end index {end} cannot be less than start index {start}")
+                    raise ValueError(
+                        f"Label configuration {i}: end index {end}"
+                        f" cannot be less than start index {start}"
+                    )
                 normalized_pages["end"] = end
             # If no end is specified, leave it out (meaning "to end of document")
 
diff --git a/src/nutrient_dws/file_handler.py b/src/nutrient_dws/file_handler.py
index a896cb6..f79cfde 100644
--- a/src/nutrient_dws/file_handler.py
+++ b/src/nutrient_dws/file_handler.py
@@ -205,21 +205,22 @@ def get_file_size(file_input: FileInput) -> int | None:
 
     return None
 
+
 def get_pdf_page_count(pdf_input: FileInput) -> int:
     """Zero dependency way to get the number of pages in a PDF.
 
     Args:
-        file_input: File path, bytes, or file-like object. Has to be of a PDF file
+        pdf_input: File path, bytes, or file-like object. Has to be of a PDF file
 
     Returns:
         Number of pages in a PDF.
     """
     if isinstance(pdf_input, (str, Path)):
-        with open(pdf_input, 'rb') as f:
+        with open(pdf_input, "rb") as f:
             pdf_bytes = f.read()
     elif isinstance(pdf_input, bytes):
         pdf_bytes = pdf_input
-    elif hasattr(pdf_input, 'read') and hasattr(pdf_input, 'seek') and hasattr(pdf_input, 'tell'):
+    elif hasattr(pdf_input, "read") and hasattr(pdf_input, "seek") and hasattr(pdf_input, "tell"):
         pos = pdf_input.tell()
         pdf_input.seek(0)
         pdf_bytes = pdf_input.read()
@@ -228,12 +229,12 @@ def get_pdf_page_count(pdf_input: FileInput) -> int:
         raise TypeError("Unsupported input type. Expected str, Path, bytes, or seekable BinaryIO.")
 
     # Find all PDF objects
-    objects = re.findall(rb'(\d+)\s+(\d+)\s+obj(.*?)endobj', pdf_bytes, re.DOTALL)
+    objects = re.findall(rb"(\d+)\s+(\d+)\s+obj(.*?)endobj", pdf_bytes, re.DOTALL)
 
     # Get the Catalog Object
     catalog_obj = None
-    for obj_num, gen_num, obj_data in objects:
-        if b'/Type' in obj_data and b'/Catalog' in obj_data:
+    for _obj_num, _gen_num, obj_data in objects:
+        if b"/Type" in obj_data and b"/Catalog" in obj_data:
             catalog_obj = obj_data
             break
 
@@ -241,22 +242,22 @@ def get_pdf_page_count(pdf_input: FileInput) -> int:
         raise ValueError("Could not find /Catalog object in PDF.")
 
     # Extract /Pages reference (e.g. 3 0 R)
-    pages_ref_match = re.search(rb'/Pages\s+(\d+)\s+(\d+)\s+R', catalog_obj)
+    pages_ref_match = re.search(rb"/Pages\s+(\d+)\s+(\d+)\s+R", catalog_obj)
     if not pages_ref_match:
         raise ValueError("Could not find /Pages reference in /Catalog.")
     pages_obj_num = pages_ref_match.group(1).decode()
     pages_obj_gen = pages_ref_match.group(2).decode()
 
     # Step 3: Find the referenced /Pages object
-    pages_obj_pattern = fr'{pages_obj_num}\s+{pages_obj_gen}\s+obj(.*?)endobj'.encode()
+    pages_obj_pattern = rf"{pages_obj_num}\s+{pages_obj_gen}\s+obj(.*?)endobj".encode()
     pages_obj_match = re.search(pages_obj_pattern, pdf_bytes, re.DOTALL)
     if not pages_obj_match:
         raise ValueError("Could not find root /Pages object.")
     pages_obj_data = pages_obj_match.group(1)
 
     # Step 4: Extract /Count
-    count_match = re.search(rb'/Count\s+(\d+)', pages_obj_data)
+    count_match = re.search(rb"/Count\s+(\d+)", pages_obj_data)
     if not count_match:
         raise ValueError("Could not find /Count in root /Pages object.")
 
-    return int(count_match.group(1))
\ No newline at end of file
+    return int(count_match.group(1))
diff --git a/tests/integration/test_direct_api_integration.py b/tests/integration/test_direct_api_integration.py
index 4ee08df..a36b1c9 100644
--- a/tests/integration/test_direct_api_integration.py
+++ b/tests/integration/test_direct_api_integration.py
@@ -273,7 +273,9 @@ def test_split_pdf_integration(self, client, sample_multipage_pdf_path, tmp_path
         # Verify the number of pages in each output PDF
         total_page_count = get_pdf_page_count(sample_multipage_pdf_path)
         assert get_pdf_page_count(result[0]) == 1  # First PDF should have 1 page
-        assert get_pdf_page_count(result[1]) == total_page_count - 1  # Second PDF should have the remaining pages
+        assert (
+            get_pdf_page_count(result[1]) == total_page_count - 1
+        )  # Second PDF should have the remaining pages
 
     def test_split_pdf_with_output_files(self, client, sample_multipage_pdf_path, tmp_path):
         """Test split_pdf method saving to output files."""
@@ -307,7 +309,9 @@ def test_split_pdf_with_output_files(self, client, sample_multipage_pdf_path, tm
 
         # Verify the number of pages in the second output PDF
         total_page_count = get_pdf_page_count(sample_multipage_pdf_path)
-        assert get_pdf_page_count(str(tmp_path / "remaining.pdf")) == total_page_count - 1 # Second PDF should have remaining pages
+        assert (
+            get_pdf_page_count(str(tmp_path / "remaining.pdf")) == total_page_count - 1
+        )  # Second PDF should have remaining pages
 
     def test_split_pdf_no_ranges_error(self, client, sample_pdf_path):
         """Test split_pdf with no ranges returns first page by default."""
@@ -396,7 +400,9 @@ def test_duplicate_pdf_pages_negative_indexes(self, client, sample_pdf_path):
         assert_is_pdf(result)
 
         # Verify the number of pages in the output PDF
-        assert get_pdf_page_count(result) == 3  # Should have 3 pages (last page, first page, last page)
+        assert (
+            get_pdf_page_count(result) == 3
+        )  # Should have 3 pages (last page, first page, last page)
 
     def test_duplicate_pdf_pages_empty_indexes_error(self, client, sample_pdf_path):
         """Test duplicate_pdf_pages method with empty page_indexes raises error."""
@@ -415,7 +421,9 @@ def test_delete_pdf_pages_basic(self, client, sample_multipage_pdf_path):
 
         # Verify the number of pages in the output PDF
         total_page_count = get_pdf_page_count(sample_multipage_pdf_path)
-        assert get_pdf_page_count(result) == total_page_count - 1  # Should have 2 pages (deleted first page from 3-page PDF)
+        assert (
+            get_pdf_page_count(result) == total_page_count - 1
+        )  # Should have 2 pages (deleted first page from 3-page PDF)
 
     def test_delete_pdf_pages_multiple(self, client, sample_multipage_pdf_path):
         """Test delete_pdf_pages method with multiple page deletion."""
@@ -428,7 +436,9 @@ def test_delete_pdf_pages_multiple(self, client, sample_multipage_pdf_path):
 
         # Verify the number of pages in the output PDF
         total_page_count = get_pdf_page_count(sample_multipage_pdf_path)
-        assert get_pdf_page_count(result) == total_page_count - 2  # Should have 1 page (deleted pages 1 and 3 from 3-page PDF)
+        assert (
+            get_pdf_page_count(result) == total_page_count - 2
+        )  # Should have 1 page (deleted pages 1 and 3 from 3-page PDF)
 
     def test_delete_pdf_pages_with_output_file(self, client, sample_multipage_pdf_path, tmp_path):
         """Test delete_pdf_pages method saving to output file."""
@@ -449,7 +459,9 @@ def test_delete_pdf_pages_with_output_file(self, client, sample_multipage_pdf_pa
 
         # Verify the number of pages in the output PDF
         total_page_count = get_pdf_page_count(sample_multipage_pdf_path)
-        assert get_pdf_page_count(output_path) == total_page_count - 1  # Should have 2 pages (deleted page 2 from 3-page PDF)
+        assert (
+            get_pdf_page_count(output_path) == total_page_count - 1
+        )  # Should have 2 pages (deleted page 2 from 3-page PDF)
 
     def test_delete_pdf_pages_negative_indexes_error(self, client, sample_pdf_path):
         """Test delete_pdf_pages method with negative indexes raises error."""
@@ -473,7 +485,9 @@ def test_delete_pdf_pages_duplicate_indexes(self, client, sample_multipage_pdf_p
 
         # Verify the number of pages in the output PDF
         total_page_count = get_pdf_page_count(sample_multipage_pdf_path)
-        assert get_pdf_page_count(result) == total_page_count - 2  # Should have 1 page (deleted pages 1 and 2 from 3-page PDF)
+        assert (
+            get_pdf_page_count(result) == total_page_count - 2
+        )  # Should have 1 page (deleted pages 1 and 2 from 3-page PDF)
 
     # Tests for add_page
     def test_add_page_at_beginning(self, client, sample_pdf_path):
diff --git a/tests/integration/test_live_api.py b/tests/integration/test_live_api.py
index 2243407..4591f42 100644
--- a/tests/integration/test_live_api.py
+++ b/tests/integration/test_live_api.py
@@ -306,7 +306,9 @@ def test_duplicate_pdf_pages_negative_indexes(self, client, sample_pdf_path):
         assert_is_pdf(result)
 
         # Verify the number of pages in the output PDF
-        assert get_pdf_page_count(result) == 3  # Should have 3 pages (last page, first page, last page)
+        assert (
+            get_pdf_page_count(result) == 3
+        )  # Should have 3 pages (last page, first page, last page)
 
     def test_duplicate_pdf_pages_empty_indexes_error(self, client, sample_pdf_path):
         """Test duplicate_pdf_pages method with empty page_indexes raises error."""
@@ -326,7 +328,9 @@ def test_delete_pdf_pages_basic(self, client, sample_pdf_path):
 
         # Verify the number of pages in the output PDF
         total_pages = get_pdf_page_count(sample_pdf_path)
-        assert get_pdf_page_count(result) == total_pages - 1  # Should have one less page than original
+        assert (
+            get_pdf_page_count(result) == total_pages - 1
+        )  # Should have one less page than original
 
     def test_delete_pdf_pages_multiple(self, client, sample_pdf_path):
         """Test delete_pdf_pages method with multiple page deletion."""
diff --git a/tests/integration/test_new_tools_integration.py b/tests/integration/test_new_tools_integration.py
index 47e5edf..7dd70e2 100644
--- a/tests/integration/test_new_tools_integration.py
+++ b/tests/integration/test_new_tools_integration.py
@@ -75,7 +75,9 @@ def test_create_redactions_preset_with_output_file(
         """Test creating redactions with preset and saving to file."""
         output_path = tmp_path / "redacted_preset.pdf"
         result = client.create_redactions_preset(
-            sample_pdf_with_sensitive_data, preset="international-phone-number", output_path=str(output_path)
+            sample_pdf_with_sensitive_data,
+            preset="international-phone-number",
+            output_path=str(output_path),
         )
         assert result is None
         assert output_path.exists()
@@ -94,7 +96,9 @@ def test_create_redactions_text(self, client, sample_pdf_with_sensitive_data):
         """Test creating redactions for exact text matches."""
         # Use a very common letter that should exist
         result = client.create_redactions_text(
-            sample_pdf_with_sensitive_data, text="a", case_sensitive=False,
+            sample_pdf_with_sensitive_data,
+            text="a",
+            case_sensitive=False,
         )
         assert_is_pdf(result)
         assert len(result) > 0