diff --git a/patacrep/files.py b/patacrep/files.py
index 51737c23..5c84e0b0 100644
--- a/patacrep/files.py
+++ b/patacrep/files.py
@@ -13,9 +13,13 @@ import sys
 LOGGER = logging.getLogger(__name__)
 
 def recursive_find(root_directory, extensions):
-    """Recursively find files matching a pattern, from a root_directory.
+    """Recursively find files with some extension, from a root_directory.
 
-    Return a list of files matching the pattern. TODO
+    Return a list of files matching those conditions.
+
+    Arguments:
+    - `extensions`: list of accepted extensions.
+    - `root_directory`: root directory of the search.
     """
     if not os.path.isdir(root_directory):
         return []