diff --git a/tox.ini b/tox.ini
index 1eb5527bbe7d55ea7efc6b1bc973c3cf049d19ac..833cb668052f30efa3292918cfbe6cbb47659425 100644
--- a/tox.ini
+++ b/tox.ini
@@ -6,7 +6,9 @@ deps =
   .[testing]
   pytest-cov
 commands =
-  pytest --cov=swh --cov-branch {posargs}
+  pytest --cov={envsitepackagesdir}/swh/model \
+         {envsitepackagesdir}/swh/model \
+           --cov-branch {posargs}
 
 [testenv:flake8]
 skip_install = true