diff --git a/tox.ini b/tox.ini
index 863f4f06c3339196dadc41ad97d3b1d581620186..26957ad8cb01c3445ce08501e51726011be98c79 100644
--- a/tox.ini
+++ b/tox.ini
@@ -8,7 +8,7 @@ whitelist_externals = poetry
 skip_install = true
 commands = pytest --pylama --cov=biscuit biscuit/core/
 setenv =
-    TEST_SCREENSHOT_PATH = {env:TEST_SCREENSHOT_PATH}
+    TEST_SCREENSHOT_PATH = {env:TEST_SCREENSHOT_PATH:}
 
 [pylama]
 linters = pycodestyle,pyflakes,radon