diff --git a/tests/test_blackboard.py b/tests/test_blackboard.py
index 12197cc..1c3c71f 100644
--- a/tests/test_blackboard.py
+++ b/tests/test_blackboard.py
@@ -339,9 +339,9 @@ class TestObservation:
         bb, _, _ = tmp_db
         bb.create_task(Task(id="t1", title="Obs"))
         bb.add_observation("t1", "a", "unresolved", severity="blocking")
-        # Both are unresolved (no resolved_by set), filter returns all
         unresolved = bb.get_observations("t1", unresolved_only=True)
-        assert len(unresolved) == 2  # both lack resolved_by
+        assert len(unresolved) == 1
+        assert unresolved[0].severity == "blocking"
 
 
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