diff --git a/pyerrors/input/utils.py b/pyerrors/input/utils.py
index 66b60f68..4e50c15c 100644
--- a/pyerrors/input/utils.py
+++ b/pyerrors/input/utils.py
@@ -2,11 +2,20 @@
 
 
 def check_idl(idl, che):
+    """Checks if list of configurations is contained in an idl
+
+    Parameters
+    ----------
+    idl : range or list
+        idl of the current replicum
+    che : list
+        list of configurations to be checked against
+    """
     missing = []
     for c in che:
         if c not in idl:
             missing.append(c)
-    # print missing such that it can directly be parsed to slurm terminal
+    # print missing configurations such that it can directly be parsed to slurm terminal
     if not (len(missing) == 0):
         print(len(missing), "configs missing")
         miss_str = str(missing[0])