diff --git a/swh/scheduler/cli/admin.py b/swh/scheduler/cli/admin.py
index c8bb619..0becbe8 100644
--- a/swh/scheduler/cli/admin.py
+++ b/swh/scheduler/cli/admin.py
@@ -1,134 +1,137 @@
 # Copyright (C) 2016-2021  The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
 # WARNING: do not import unnecessary things here to keep cli startup time under
 # control
 import logging
 import time
 
 import click
 
 from . import cli
 
 
 @cli.command("start-runner")
 @click.option(
     "--period",
     "-p",
     default=0,
     help=(
         "Period (in s) at witch pending tasks are checked and "
         "executed. Set to 0 (default) for a one shot."
     ),
 )
 @click.option(
     "--task-type",
     "task_type_names",
     multiple=True,
     default=[],
-    help="Task type names (e.g load-git, load-hg, list-github-full, ...) to schedule.",
+    help=(
+        "Task types to schedule. If not provided, this iterates over every "
+        "task types referenced in the scheduler backend."
+    ),
 )
 @click.option(
     "--with-priority/--without-priority",
     is_flag=True,
     default=False,
     help=(
         "Determine if those tasks should be the ones with priority or not."
         "By default, this deals with tasks without any priority."
     ),
 )
 @click.pass_context
 def runner(ctx, period, task_type_names, with_priority):
     """Starts a swh-scheduler runner service.
 
     This process is responsible for checking for ready-to-run tasks and
     schedule them."""
     from swh.scheduler.celery_backend.config import build_app
     from swh.scheduler.celery_backend.runner import run_ready_tasks
 
     config = ctx.obj["config"]
     app = build_app(config.get("celery"))
     app.set_current()
 
     logger = logging.getLogger(__name__ + ".runner")
     scheduler = ctx.obj["scheduler"]
     logger.debug("Scheduler %s" % scheduler)
     task_types = []
     for task_type_name in task_type_names:
         task_type = scheduler.get_task_type(task_type_name)
         if not task_type:
             raise ValueError(f"Unknown {task_type_name}")
         task_types.append(task_type)
 
     try:
         while True:
             logger.debug("Run ready tasks")
             try:
                 ntasks = len(run_ready_tasks(scheduler, app, task_types, with_priority))
                 if ntasks:
                     logger.info("Scheduled %s tasks", ntasks)
             except Exception:
                 logger.exception("Unexpected error in run_ready_tasks()")
             if not period:
                 break
             time.sleep(period)
     except KeyboardInterrupt:
         ctx.exit(0)
 
 
 @cli.command("start-listener")
 @click.pass_context
 def listener(ctx):
     """Starts a swh-scheduler listener service.
 
     This service is responsible for listening at task lifecycle events and
     handle their workflow status in the database."""
     scheduler_backend = ctx.obj["scheduler"]
     if not scheduler_backend:
         raise ValueError("Scheduler class (local/remote) must be instantiated")
 
     broker = (
         ctx.obj["config"]
         .get("celery", {})
         .get("task_broker", "amqp://guest@localhost/%2f")
     )
 
     from swh.scheduler.celery_backend.pika_listener import get_listener
 
     listener = get_listener(broker, "celeryev.listener", scheduler_backend)
     try:
         listener.start_consuming()
     finally:
         listener.stop_consuming()
 
 
 @cli.command("rpc-serve")
 @click.option("--host", default="0.0.0.0", help="Host to run the scheduler server api")
 @click.option("--port", default=5008, type=click.INT, help="Binding port of the server")
 @click.option(
     "--debug/--nodebug",
     default=None,
     help=(
         "Indicates if the server should run in debug mode. "
         "Defaults to True if log-level is DEBUG, False otherwise."
     ),
 )
 @click.pass_context
 def rpc_server(ctx, host, port, debug):
     """Starts a swh-scheduler API HTTP server.
     """
     if ctx.obj["config"]["scheduler"]["cls"] == "remote":
         click.echo(
             "The API server can only be started with a 'local' " "configuration",
             err=True,
         )
         ctx.exit(1)
 
     from swh.scheduler.api import server
 
     server.app.config.update(ctx.obj["config"])
     if debug is None:
         debug = ctx.obj["log_level"] <= logging.DEBUG
     server.app.run(host, port=port, debug=bool(debug))