--- a/taskcluster/actions/run_missing_tests.py
+++ b/taskcluster/actions/run_missing_tests.py
@@ -25,17 +25,16 @@ logger = logging.getLogger(__name__)
     description="""
     Run tests in the selected push that were optimized away, usually by SETA.
 
     This action is for use on pushes that will be merged into another branch,
     to check that optimization hasn't hidden any failures.
     """,
     order=100,  # Useful for sheriffs, but not top of the list
     context=[],  # Applies to any task
-    schema={},
 )
 def run_missing_tests(parameters, input, task_group_id, task_id, task):
     decision_task_id = find_decision_task(parameters)
 
     full_task_graph = get_artifact(decision_task_id, "public/full-task-graph.json")
     _, full_task_graph = TaskGraph.from_json(full_task_graph)
     target_tasks = get_artifact(decision_task_id, "public/target-tasks.json")
     label_to_taskid = get_artifact(decision_task_id, "public/label-to-taskid.json")