--- a/taskcluster/taskgraph/actions/add_new_jobs.py
+++ b/taskcluster/taskgraph/actions/add_new_jobs.py
@@ -14,17 +14,17 @@ from taskgraph.util.taskcluster import g
 from taskgraph.util.parameterization import resolve_task_references
 from taskgraph.taskgraph import TaskGraph
 
 
 @register_callback_action(
     name='add-new-jobs',
     title='Add new jobs',
     symbol='add-new',
-    description="Add new jobs using task labels",
+    description="Add new jobs using task labels.",
     order=10000,
     context=[],
     schema={
         'type': 'object',
         'properties': {
             'tasks': {
                 'type': 'array',
                 'description': 'An array of task labels',

--- a/taskcluster/taskgraph/actions/retrigger.py
+++ b/taskcluster/taskgraph/actions/retrigger.py
@@ -7,17 +7,21 @@
 from __future__ import absolute_import, print_function, unicode_literals
 
 from .registry import register_task_action
 
 
 @register_task_action(
     title='Retrigger',
     name='retrigger',
-    description='Create a clone of the task',
+    description=(
+        'Create a clone of the task.\n\n'
+        'This does not update any dependencies or '
+        'cause any downstream tasks to be retriggered.'
+    ),
     order=1,
     context=[{}],
 )
 def retrigger_task_builder(parameters):
 
     new_expires = '30 days'
 
     return {

--- a/taskcluster/taskgraph/actions/run_missing_tests.py
+++ b/taskcluster/taskgraph/actions/run_missing_tests.py
@@ -17,24 +17,24 @@ from taskgraph.taskgraph import TaskGrap
 
 logger = logging.getLogger(__name__)
 
 
 @register_callback_action(
     name='run-missing-tests',
     title='Run Missing Tests',
     symbol='rmt',
-    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.
-    """,
+    description=(
+        "Run tests in the selected push that were optimized away, usually by SETA."
+        "\n"
+        "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
+    context=[],  # Applies to decision task
 )
 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")