diff --git a/codemcp/git_query.py b/codemcp/git_query.py
index 1e3296c..15399a3 100644
--- a/codemcp/git_query.py
+++ b/codemcp/git_query.py
@@ -262,8 +262,11 @@ async def get_current_commit_hash(directory: str, short: bool = True) -> str | N
     Returns:
         The current commit hash if available, None otherwise
 
+    Raises:
+        NotADirectoryError: If the provided path is a file instead of a directory
+
     Note:
-        This function safely returns None if there are any issues getting the hash,
+        This function safely returns None for other issues getting the hash,
         rather than raising exceptions.
     """
     try:
@@ -287,6 +290,9 @@ async def get_current_commit_hash(directory: str, short: bool = True) -> str | N
         if result.returncode == 0:
             return str(result.stdout.strip())
         return None
+    except NotADirectoryError:
+        # Re-raise NotADirectoryError as a hard error
+        raise
     except Exception as e:
         logging.warning(
             f"Exception when getting current commit hash: {e!s}", exc_info=True
diff --git a/codemcp/testing.py b/codemcp/testing.py
index 7024eef..cc8a028 100644
--- a/codemcp/testing.py
+++ b/codemcp/testing.py
@@ -110,7 +110,9 @@ async def setup_repository(self):
         try:
             await self.git_run(["init", "-b", "main"])
         except subprocess.CalledProcessError:
-            self.fail("git version is too old for tests! Please install a newer version of git.")
+            self.fail(
+                "git version is too old for tests! Please install a newer version of git."
+            )
         await self.git_run(["config", "user.email", "test@example.com"])
         await self.git_run(["config", "user.name", "Test User"])
 
diff --git a/e2e/test_git_query_file_path.py b/e2e/test_git_query_file_path.py
new file mode 100644
index 0000000..2efa756
--- /dev/null
+++ b/e2e/test_git_query_file_path.py
@@ -0,0 +1,29 @@
+#!/usr/bin/env python3
+
+"""Tests for the get_current_commit_hash function when passed a file path."""
+
+import os
+import unittest
+
+from codemcp.git_query import get_current_commit_hash
+from codemcp.testing import MCPEndToEndTestCase
+
+
+class GitQueryFilePathTest(MCPEndToEndTestCase):
+    """Test that get_current_commit_hash raises a NotADirectoryError when passed a file path."""
+
+    async def test_file_path_raises_error(self):
+        """Test that passing a file path to get_current_commit_hash raises NotADirectoryError."""
+        # Create a test file in the temp dir
+        test_file_path = os.path.join(self.temp_dir.name, "test_file.txt")
+        with open(test_file_path, "w") as f:
+            f.write("Test content")
+
+        # Attempt to get current commit hash using a file path instead of directory
+        # This should raise a NotADirectoryError
+        with self.assertRaises(NotADirectoryError):
+            await get_current_commit_hash(test_file_path)
+
+
+if __name__ == "__main__":
+    unittest.main()