diff --git a/compare_checksums.py b/compare_checksums.py
old mode 100644
new mode 100755
index a1c7a3d..232d5bf
--- a/compare_checksums.py
+++ b/compare_checksums.py
@@ -17,27 +17,18 @@ ZFS_ELAB_PREFIX = "elabfs-"
 TMP_BACKUP_FOLDER = "/mnt/Datenspeicher/snap-backup-dataset/temporary-backups"
 
 
-def xremote_call(arguments):
-    """ makes runs an command on the remote backup server
-
-    :params arguments: list of command line arguments and parameters
-    :returns: string of the command output
-    :raises subprocess.CalledProcessError: if command has not an exit value of 0
-    """
-    cmd = ["ssh", "-i", SSH_KEY_FILE, SSH_REMOTE]
-    cmd.extend(arguments)
-    result = subprocess.run(" ".join(cmd), check=True,
-        stdout=subprocess.PIPE,
-        universal_newlines=True, shell=True)
-    return result.stdout
-
-
 def get_local_backups():
+    """ returns a list of .gz files in the local temp backup folder """
     tmp_folder = pathlib.Path(TMP_BACKUP_FOLDER)
     return [i for i in tmp_folder.iterdir() if i.suffix==".gz"]
 
 
 def get_remote_checksum(local_backup_path):
+    """ gets the checksum of a remote backup of a local file
+
+    :params local_backup_path: path of the local backup file
+    :returns: sh256 hash of the remote backup or None
+    """
     member = get_member_name(local_backup_path.name)
     remote_path =  f"{REMOTE_PATH}/{member}/{local_backup_path.name}"
     try:
@@ -48,11 +39,17 @@ def get_remote_checksum(local_backup_path):
         return None
 
 def get_local_checksum(local_backup_path):
+    """ gets the checksum of a local file
+
+    :params local_backup_path: path of the local backup file
+    :returns: sh256 hash of the file or None
+    """
     result = call(["sha256", str(local_backup_path)], as_text=True)
     parts = result.split("=")
     return parts[1].strip()
 
-def batch_check():
+def batch_compare():
+    """ compares local file checksums to the remote backups """
     for local_backup_path in get_local_backups():
         remote_checksum = get_remote_checksum(local_backup_path)
         local_checksum = get_local_checksum(local_backup_path)
@@ -63,4 +60,4 @@ def batch_check():
 
 
 if __name__ == "__main__":
-    batch_check()
+    batch_compare()