diff --git a/README.rst b/README.rst
index f76e7e4..9c0a46a 100644
--- a/README.rst
+++ b/README.rst
@@ -104,6 +104,8 @@ These are the flags you can use when calling ``pytest`` in the command line:
* ``--image_cache_dir
`` sets the image cache dir. This will override any
configuration, see below.
+* ``--reset_only_failed`` reset the image cache of the failed tests only.
+
Test specific flags
-------------------
These are attributes of `verify_image_cache`. You can set them as ``True`` if needed