--- a/taskcluster/taskgraph/decision.py
+++ b/taskcluster/taskgraph/decision.py
@@ -64,17 +64,17 @@ def taskgraph_decision(options):
     # write out the parameters used to generate this graph
     write_artifact('parameters.yml', dict(**parameters))
 
     # write out the full graph for reference
     write_artifact('full-task-graph.json',
                    taskgraph_to_json(tgg.full_task_graph))
 
     # write out the target task set to allow reproducing this as input
-    write_artifact('target_tasks.json',
+    write_artifact('target-tasks.json',
                    tgg.target_task_set.tasks.keys())
 
     # write out the optimized task graph to describe what will actually happen,
     # and the map of labels to taskids
     write_artifact('task-graph.json',
                    taskgraph_to_json(tgg.optimized_task_graph))
     write_artifact('label-to-taskid.json', tgg.label_to_taskid)