feat(smolvla2): --mode flag, skip task picker with --task, timed /action

Lets the operator skip the interactive startup entirely and go straight
to the command line:

- New --mode {action,question} arg; when given, the startup mode prompt
  is skipped.
- When --task is passed explicitly on the CLI, the startup task picker
  is skipped (the dataset-bootstrap task still shows the picker so you
  can override it).

Also adds a timed action burst: /action <seconds> runs the robot for N
seconds, then the autonomous loop auto-reverts to question mode and
clears the action queue. Plain /action stays unlimited.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/lerobot/scripts/lerobot_smolvla2_runtime.py

@@ -139,7 +139,23 @@ def _parse_args(argv: list[str] | None = None) -> argparse.Namespace:
         dest="task",
         type=str,
         default=None,
-        help="Initial task. If omitted, the first stdin line is treated as the task.",
+        help=(
+            "Initial task. When given, the startup task picker is skipped "
+            "and this task is used directly. If omitted, the picker is "
+            "shown (or the first stdin line is treated as the task)."
+        ),
+    )
+    p.add_argument(
+        "--mode",
+        dest="mode",
+        type=str,
+        choices=["action", "question"],
+        default=None,
+        help=(
+            "Start-up run mode. 'action' runs the robot; 'question' starts "
+            "paused for VQA. When given, the startup mode prompt is "
+            "skipped. Can still be flipped at runtime with /action /question."
+        ),
     )
     p.add_argument(
         "--no_robot",
@@ -991,6 +1007,7 @@ def _print_runtime_help() -> None:
     print(
         "[smolvla2] commands:\n"
         "  /action            run the robot (default mode)\n"
+        "  /action <seconds>  run the robot for N seconds, then auto-pause to question\n"
         "  /question          pause the action loop; typed lines become VQA questions\n"
         "  /help              show this help\n"
         "  task: <text>       switch task (clears plan / memory / subtask)\n"
@@ -1003,17 +1020,40 @@ def _print_runtime_help() -> None:
 def _handle_slash_command(runtime: Any, line: str) -> bool:
     """Handle ``/action`` / ``/question`` / ``/help``.
 
-    ``/vlm`` and ``/vqa`` are kept as aliases for ``/question``. Returns
-    ``True`` when ``line`` was a recognised command (and was consumed),
-    ``False`` otherwise.
+    ``/action`` accepts an optional duration — ``/action 10`` runs the
+    robot for 10 seconds, then the autonomous loop auto-reverts to
+    ``question`` mode. ``/vlm`` and ``/vqa`` are aliases for
+    ``/question``. Returns ``True`` when ``line`` was a recognised
+    command (and was consumed), ``False`` otherwise.
     """
-    cmd = line.strip().lower()
+    parts = line.strip().split()
+    if not parts:
+        return False
+    cmd = parts[0].lower()
     if cmd in {"/action", "/act"}:
         runtime.state["mode"] = "action"
-        print("[smolvla2] mode: action — robot running", flush=True)
+        seconds: float | None = None
+        if len(parts) > 1:
+            try:
+                seconds = float(parts[1])
+            except ValueError:
+                seconds = None
+        if seconds is not None and seconds > 0:
+            import time as _time  # noqa: PLC0415
+
+            runtime.state["action_deadline"] = _time.monotonic() + seconds
+            print(
+                f"[smolvla2] mode: action — running for {seconds:g}s, "
+                "then back to question",
+                flush=True,
+            )
+        else:
+            runtime.state["action_deadline"] = None
+            print("[smolvla2] mode: action — robot running", flush=True)
         return True
     if cmd in {"/question", "/q", "/vlm", "/vqa"}:
         runtime.state["mode"] = "question"
+        runtime.state["action_deadline"] = None
         # Drop any queued chunk so no stale action fires while paused.
         queue = runtime.state.get("action_queue")
         if hasattr(queue, "clear"):
@@ -1129,14 +1169,30 @@ def _run_autonomous(
 
     def _panel_loop() -> None:
         while not _panel_stop.is_set():
-            if runtime.state.get("mode", "action") == "action":
-                try:
-                    redraw()
-                    # Re-print the prompt the redraw just cleared so the
-                    # operator always has a visible ``> `` to type at.
-                    print("> ", end="", flush=True)
-                except Exception:  # noqa: BLE001
-                    pass
+            st = runtime.state
+            if st.get("mode", "action") == "action":
+                # Timed burst (``/action <seconds>``): once the deadline
+                # passes, auto-revert to question mode and clear the
+                # queue so the robot stops.
+                deadline = st.get("action_deadline")
+                if deadline is not None and time.monotonic() >= deadline:
+                    st["mode"] = "question"
+                    st["action_deadline"] = None
+                    queue = st.get("action_queue")
+                    if hasattr(queue, "clear"):
+                        queue.clear()
+                    print(
+                        "\n[smolvla2] timed action elapsed — back to question mode",
+                        flush=True,
+                    )
+                else:
+                    try:
+                        redraw()
+                        # Re-print the prompt the redraw just cleared so
+                        # the operator always has a visible ``> ``.
+                        print("> ", end="", flush=True)
+                    except Exception:  # noqa: BLE001
+                        pass
             _panel_stop.wait(0.7)
 
     panel_thread = threading.Thread(
@@ -1446,6 +1502,11 @@ def main(argv: list[str] | None = None) -> int:
     # autonomous robot mode benefit, since the model is memorised on
     # the exact training prompts and matching wording is what gets
     # recall to fire.
+    # Was a task given explicitly on the CLI? Captured before the
+    # dataset bootstrap fills ``args.task`` — an explicit ``--task``
+    # skips the startup task picker entirely.
+    cli_task_given = args.task is not None
+
     bootstrap_state: dict[str, str] = {}
     if args.dataset_repo_id is not None:
         bootstrap_state = _bootstrap_state_from_dataset(
@@ -1461,15 +1522,17 @@ def main(argv: list[str] | None = None) -> int:
             )
 
     # Startup mode prompt — choose action (run the robot) vs question
-    # (VQA only) *before* the task picker, so the operator sets intent
-    # up front. It can still be flipped any time with /action /question.
-    startup_mode = _select_mode_interactively()
+    # (VQA only) *before* the task picker. Skipped when ``--mode`` was
+    # passed on the CLI. Can still be flipped at runtime with
+    # /action /question.
+    startup_mode = args.mode or _select_mode_interactively()
 
-    # Always offer the startup task picker on an interactive terminal:
-    # list the dataset's tasks (the canonical / --task one shown as the
-    # default) so the operator can pick another or type a custom task.
-    # Non-TTY runs keep the "first stdin line is the task" path.
-    args.task = _select_task_interactively(ds_meta, args.task)
+    # Startup task picker — list the dataset's tasks so the operator can
+    # pick one or type a custom task. Skipped when ``--task`` was passed
+    # explicitly on the CLI. Non-TTY runs keep the "first stdin line is
+    # the task" path.
+    if not cli_task_given:
+        args.task = _select_task_interactively(ds_meta, args.task)
 
     observation_provider: Callable[[], dict | None] | None = None
     robot_executor: Callable[[Any], None] | None = None