diff --git a/dreamer4/dreamer4.py b/dreamer4/dreamer4.py
index e966349..a12d86a 100644
--- a/dreamer4/dreamer4.py
+++ b/dreamer4/dreamer4.py
@@ -1859,7 +1859,7 @@ class DynamicsWorldModel(Module):
         if isinstance(tasks, int):
             tasks = torch.full((batch_size,), tasks, device = self.device)
 
-        assert tasks.shape[0] == batch_size
+        assert not exists(tasks) or tasks.shape[0] == batch_size
 
         # get state latent shape
 
diff --git a/pyproject.toml b/pyproject.toml
index 8e7ad54..eac1e34 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [project]
 name = "dreamer4"
-version = "0.0.33"
+version = "0.0.34"
 description = "Dreamer 4"
 authors = [
     { name = "Phil Wang", email = "lucidrains@gmail.com" }