diff --git a/loopy/kernel/__init__.py b/loopy/kernel/__init__.py
index 8d59b528a603da548f528b2692b9cdecfc31c51a..e042e9ec4af28fe4ea451be5982766443f1cb31a 100644
--- a/loopy/kernel/__init__.py
+++ b/loopy/kernel/__init__.py
@@ -219,8 +219,9 @@ class LoopKernel(ImmutableRecordWithoutPickling):
             intersected in slab decomposition, their grid sizes shouldn't
             change. This provides a way to forward sub-kernel grid size requests.
 
-        :arg uniquify_instruction_ids: Ensure all instruction ids are unique.
-            If *False*, does not look at `instructions`.
+        :arg uniquify_instruction_ids: Ensure all instruction ids are unique and
+            convert any IDs that are :class:`loopy.UniqueName` or *None* into
+            appropriate strings. If *False*, does not look at `instructions`.
         """
 
         if cache_manager is None: