address minor review comments

docs/source/installation.mdx

@@ -133,16 +133,16 @@ Then, install the library in editable mode. This is useful if you plan to contri
 <hfoptions id="install_lerobot_src">
 <hfoption id="conda">
 ```bash
-pip install -e ".[robot]"    # For real robot workflows (recording, replaying)
+pip install -e ".[core_scripts]"  # For robot workflows (recording, replaying, calibrate)
-pip install -e ".[training]" # For training policies
+pip install -e ".[training]"      # For training policies
-pip install -e ".[all]"      # Everything (all policies, envs, hardware, dev tools)
+pip install -e ".[all]"           # Everything (all policies, envs, hardware, dev tools)
 ```
 </hfoption>
 <hfoption id="uv">
 ```bash
-uv pip install -e ".[robot]"    # For real robot workflows (recording, replaying)
+uv pip install -e ".[core_scripts]"  # For robot workflows (recording, replaying, calibrate)
-uv pip install -e ".[training]" # For training policies
+uv pip install -e ".[training]"      # For training policies
-uv pip install -e ".[all]"      # Everything (all policies, envs, hardware, dev tools)
+uv pip install -e ".[all]"           # Everything (all policies, envs, hardware, dev tools)
 ```
 </hfoption>
 </hfoptions>
@@ -183,17 +183,17 @@ LeRobot provides **feature-scoped extras** that map to common workflows. If you
 
 **Composite Extras** combine feature extras for common CLI scripts:
 
-| Extra         | Includes                       | Typical use case                                        |
+| Extra          | Includes                       | Typical use case                                        |
-| ------------- | ------------------------------ | ------------------------------------------------------- |
+| -------------- | ------------------------------ | ------------------------------------------------------- |
-| `robot`       | `dataset` + `hardware` + `viz` | `lerobot-record`, `lerobot-replay`, `lerobot-calibrate` |
+| `core_scripts` | `dataset` + `hardware` + `viz` | `lerobot-record`, `lerobot-replay`, `lerobot-calibrate` |
-| `evaluation`  | `av`                           | `lerobot-eval` (add policy + env extras as needed)      |
+| `evaluation`   | `av`                           | `lerobot-eval` (add policy + env extras as needed)      |
-| `dataset_viz` | `dataset` + `viz`              | `lerobot-dataset-viz`, `lerobot-imgtransform-viz`       |
+| `dataset_viz`  | `dataset` + `viz`              | `lerobot-dataset-viz`, `lerobot-imgtransform-viz`       |
 
 ```bash
-pip install 'lerobot[robot]'          # Record, replay, calibrate
+pip install 'lerobot[core_scripts]'          # Record, replay, calibrate
-pip install 'lerobot[training]'       # Train policies
+pip install 'lerobot[training]'              # Train policies
-pip install 'lerobot[robot,training]' # Record + train
+pip install 'lerobot[core_scripts,training]' # Record + train
-pip install 'lerobot[all]'            # Everything
+pip install 'lerobot[all]'                   # Everything
 ```
 
 **Policy, environment, and hardware extras** are still available for specific dependencies:
@@ -206,7 +206,7 @@ pip install 'lerobot[aloha,pusht]'    # Simulation environments
 pip install 'lerobot[feetech]'        # Feetech motor support
 ```
 
-_Multiple extras can be combined (e.g., `.[robot,pi,pusht]`). For a full list of available extras, refer to `pyproject.toml`._
+_Multiple extras can be combined (e.g., `.[core_scripts,pi,pusht]`). For a full list of available extras, refer to `pyproject.toml`._
 
 ### Troubleshooting
 

pyproject.toml

@@ -118,7 +118,7 @@ build = [
 
 # ── User-facing composite extras (map to CLI scripts) ─────
 # lerobot-record, lerobot-replay, lerobot-calibrate, lerobot-teleoperate, etc.
-robot = ["lerobot[dataset]", "lerobot[hardware]", "lerobot[viz]"]
+core_scripts = ["lerobot[dataset]", "lerobot[hardware]", "lerobot[viz]"]
 # lerobot-eval -- base evaluation framework. You also need the policy's extra (e.g., lerobot[pi])
 # and the environment's extra (e.g., lerobot[pusht]) if evaluating in simulation.
 evaluation = ["lerobot[av-dep]"]

src/lerobot/__init__.py

@@ -24,11 +24,11 @@ model and dataset sharing.
 The base install is intentionally lightweight. Feature-specific dependencies
 are gated behind optional extras::
 
-    pip install 'lerobot[dataset]'   # dataset loading & creation
+    pip install 'lerobot[dataset]'       # dataset loading & creation
-    pip install 'lerobot[training]'  # training loop + wandb
+    pip install 'lerobot[training]'      # training loop + wandb
-    pip install 'lerobot[hardware]'  # real robot control
+    pip install 'lerobot[hardware]'      # real robot control
-    pip install 'lerobot[robot]'     # dataset + hardware + viz (recording)
+    pip install 'lerobot[core_scripts]'  # dataset + hardware + viz (record, replay, calibrate, etc.)
-    pip install 'lerobot[all]'       # everything
+    pip install 'lerobot[all]'           # everything
 """
 
 from lerobot.__version__ import __version__

src/lerobot/envs/__init__.py

@@ -13,11 +13,10 @@
 # limitations under the License.
 
 # NOTE: gymnasium is currently a core dependency but is a candidate for moving to an
-# optional extra in the future. This guard is here to ensure a clear error message
+# optional extra in the future. When that transition happens, uncomment the guard below
-# if/when that transition happens.
+# and update the extra name to the one that will contain gymnasium.
-from lerobot.utils.import_utils import require_package
+# from lerobot.utils.import_utils import require_package
-
+# require_package("gymnasium", extra="<update_extra>", import_name="gymnasium")
-require_package("gymnasium", extra="evaluation", import_name="gymnasium")
 
 from .configs import AlohaEnv, EnvConfig, HILSerlRobotEnvConfig, HubEnvConfig, PushtEnv
 from .factory import make_env, make_env_config, make_env_pre_post_processors

src/lerobot/motors/dynamixel/dynamixel.py

@@ -90,21 +90,6 @@ class TorqueMode(Enum):
     DISABLED = 0
 
 
-def _split_into_byte_chunks(value: int, length: int) -> list[int]:
-    if length == 1:
-        data = [value]
-    elif length == 2:
-        data = [dxl.DXL_LOBYTE(value), dxl.DXL_HIBYTE(value)]
-    elif length == 4:
-        data = [
-            dxl.DXL_LOBYTE(dxl.DXL_LOWORD(value)),
-            dxl.DXL_HIBYTE(dxl.DXL_LOWORD(value)),
-            dxl.DXL_LOBYTE(dxl.DXL_HIWORD(value)),
-            dxl.DXL_HIBYTE(dxl.DXL_HIWORD(value)),
-        ]
-    return data
-
-
 class DynamixelMotorsBus(SerialMotorsBus):
     """
     The Dynamixel implementation for a MotorsBus. It relies on the python dynamixel sdk to communicate with
@@ -249,7 +234,18 @@ class DynamixelMotorsBus(SerialMotorsBus):
         return half_turn_homings
 
     def _split_into_byte_chunks(self, value: int, length: int) -> list[int]:
-        return _split_into_byte_chunks(value, length)
+        if length == 1:
+            data = [value]
+        elif length == 2:
+            data = [dxl.DXL_LOBYTE(value), dxl.DXL_HIBYTE(value)]
+        elif length == 4:
+            data = [
+                dxl.DXL_LOBYTE(dxl.DXL_LOWORD(value)),
+                dxl.DXL_HIBYTE(dxl.DXL_LOWORD(value)),
+                dxl.DXL_LOBYTE(dxl.DXL_HIWORD(value)),
+                dxl.DXL_HIBYTE(dxl.DXL_HIWORD(value)),
+            ]
+        return data
 
     def broadcast_ping(self, num_retry: int = 0, raise_on_error: bool = False) -> dict[int, int] | None:
         for n_try in range(1 + num_retry):

src/lerobot/motors/feetech/feetech.py

@@ -73,21 +73,6 @@ class TorqueMode(Enum):
     DISABLED = 0
 
 
-def _split_into_byte_chunks(value: int, length: int) -> list[int]:
-    if length == 1:
-        data = [value]
-    elif length == 2:
-        data = [scs.SCS_LOBYTE(value), scs.SCS_HIBYTE(value)]
-    elif length == 4:
-        data = [
-            scs.SCS_LOBYTE(scs.SCS_LOWORD(value)),
-            scs.SCS_HIBYTE(scs.SCS_LOWORD(value)),
-            scs.SCS_LOBYTE(scs.SCS_HIWORD(value)),
-            scs.SCS_HIBYTE(scs.SCS_HIWORD(value)),
-        ]
-    return data
-
-
 def patch_setPacketTimeout(self, packet_length):  # noqa: N802
     """
     HACK: This patches the PortHandler behavior to set the correct packet timeouts.
@@ -332,7 +317,18 @@ class FeetechMotorsBus(SerialMotorsBus):
         return ids_values
 
     def _split_into_byte_chunks(self, value: int, length: int) -> list[int]:
-        return _split_into_byte_chunks(value, length)
+        if length == 1:
+            data = [value]
+        elif length == 2:
+            data = [scs.SCS_LOBYTE(value), scs.SCS_HIBYTE(value)]
+        elif length == 4:
+            data = [
+                scs.SCS_LOBYTE(scs.SCS_LOWORD(value)),
+                scs.SCS_HIBYTE(scs.SCS_LOWORD(value)),
+                scs.SCS_LOBYTE(scs.SCS_HIWORD(value)),
+                scs.SCS_HIBYTE(scs.SCS_HIWORD(value)),
+            ]
+        return data
 
     def _broadcast_ping(self) -> tuple[dict[int, int], int]:
         data_list: dict[int, int] = {}

src/lerobot/scripts/lerobot_calibrate.py

@@ -15,6 +15,8 @@
 """
 Helper to recalibrate your device (robot or teleoperator).
 
+Requires: pip install 'lerobot[hardware]'
+
 Example:
 
 ```shell

src/lerobot/scripts/lerobot_dataset_viz.py

@@ -15,6 +15,8 @@
 # limitations under the License.
 """ Visualize data of **all** frames of any episode of a dataset of type LeRobotDataset.
 
+Requires: pip install 'lerobot[dataset_viz]'  (includes dataset + viz extras)
+
 Note: The last frame of the episode doesn't always correspond to a final state.
 That's because our datasets are composed of transition from state to state up to
 the antepenultimate state associated to the ultimate action to arrive in the final state.

src/lerobot/scripts/lerobot_edit_dataset.py

@@ -17,6 +17,8 @@
 """
 Edit LeRobot datasets using various transformation tools.
 
+Requires: pip install 'lerobot[dataset]'
+
 This script allows you to delete episodes, split datasets, merge datasets,
 remove features, modify tasks, recompute stats, and convert image datasets to video format.
 When new_repo_id is specified, creates a new dataset.

src/lerobot/scripts/lerobot_eval.py

@@ -15,6 +15,9 @@
 # limitations under the License.
 """Evaluate a policy on an environment by running rollouts and computing metrics.
 
+Requires: pip install 'lerobot[evaluation]' plus the policy extra (e.g. lerobot[pi])
+          and the environment extra (e.g. lerobot[pusht]) if evaluating in simulation.
+
 Usage examples:
 
 You want to evaluate a model from the hub (eg: https://huggingface.co/lerobot/diffusion_pusht)

src/lerobot/scripts/lerobot_record.py

@@ -15,6 +15,8 @@
 """
 Records a dataset. Actions for the robot can be either generated by teleoperation or by a policy.
 
+Requires: pip install 'lerobot[core_scripts]'  (includes dataset + hardware + viz extras)
+
 Example:
 
 ```shell

src/lerobot/scripts/lerobot_replay.py

@@ -15,6 +15,8 @@
 """
 Replays the actions of an episode from a dataset on a robot.
 
+Requires: pip install 'lerobot[core_scripts]'  (includes dataset + hardware + viz extras)
+
 Examples:
 
 ```shell

src/lerobot/scripts/lerobot_teleoperate.py

@@ -15,6 +15,8 @@
 """
 Simple script to control a robot from teleoperation.
 
+Requires: pip install 'lerobot[hardware]'
+
 Example:
 
 ```shell

src/lerobot/scripts/lerobot_train.py

@@ -13,6 +13,11 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+"""Train a policy.
+
+Requires: pip install 'lerobot[training]'  (includes dataset + accelerate + wandb extras)
+"""
+
 import dataclasses
 import logging
 import time

tests/mocks/mock_dynamixel.py

@@ -21,10 +21,25 @@ import dynamixel_sdk as dxl
 import serial
 from mock_serial.mock_serial import MockSerial
 
-from lerobot.motors.dynamixel.dynamixel import _split_into_byte_chunks
-
 from .mock_serial_patch import WaitableStub
 
+
+def _split_into_byte_chunks(value: int, length: int) -> list[int]:
+    """Split an integer into a list of byte-sized integers (little-endian)."""
+    if length == 1:
+        data = [value]
+    elif length == 2:
+        data = [dxl.DXL_LOBYTE(value), dxl.DXL_HIBYTE(value)]
+    elif length == 4:
+        data = [
+            dxl.DXL_LOBYTE(dxl.DXL_LOWORD(value)),
+            dxl.DXL_HIBYTE(dxl.DXL_LOWORD(value)),
+            dxl.DXL_LOBYTE(dxl.DXL_HIWORD(value)),
+            dxl.DXL_HIBYTE(dxl.DXL_HIWORD(value)),
+        ]
+    return data
+
+
 # https://emanual.robotis.com/docs/en/dxl/crc/
 DXL_CRC_TABLE = [
     0x0000, 0x8005, 0x800F, 0x000A, 0x801B, 0x001E, 0x0014, 0x8011,

tests/mocks/mock_feetech.py

@@ -21,11 +21,27 @@ import scservo_sdk as scs
 import serial
 from mock_serial import MockSerial
 
-from lerobot.motors.feetech.feetech import _split_into_byte_chunks, patch_setPacketTimeout
+from lerobot.motors.feetech.feetech import patch_setPacketTimeout
 
 from .mock_serial_patch import WaitableStub
 
 
+def _split_into_byte_chunks(value: int, length: int) -> list[int]:
+    """Split an integer into a list of byte-sized integers (little-endian)."""
+    if length == 1:
+        data = [value]
+    elif length == 2:
+        data = [scs.SCS_LOBYTE(value), scs.SCS_HIBYTE(value)]
+    elif length == 4:
+        data = [
+            scs.SCS_LOBYTE(scs.SCS_LOWORD(value)),
+            scs.SCS_HIBYTE(scs.SCS_LOWORD(value)),
+            scs.SCS_LOBYTE(scs.SCS_HIWORD(value)),
+            scs.SCS_HIBYTE(scs.SCS_HIWORD(value)),
+        ]
+    return data
+
+
 class MockFeetechPacket(abc.ABC):
     @classmethod
     def build(cls, scs_id: int, params: list[int], length: int, *args, **kwargs) -> bytes:

uv.lock

@@ -2304,6 +2304,18 @@ build = [
 can-dep = [
     { name = "python-can" },
 ]
+core-scripts = [
+    { name = "av" },
+    { name = "datasets" },
+    { name = "deepdiff" },
+    { name = "jsonlines" },
+    { name = "pandas" },
+    { name = "pyarrow" },
+    { name = "pynput" },
+    { name = "pyserial" },
+    { name = "rerun-sdk" },
+    { name = "torchcodec", marker = "(platform_machine != 'aarch64' and platform_machine != 'arm64' and platform_machine != 'armv7l' and sys_platform == 'linux') or (platform_machine != 'x86_64' and sys_platform == 'darwin') or (sys_platform != 'darwin' and sys_platform != 'linux' and sys_platform != 'win32')" },
+]
 damiao = [
     { name = "python-can" },
 ]
@@ -2477,18 +2489,6 @@ qwen-vl-utils-dep = [
 reachy2 = [
     { name = "reachy2-sdk" },
 ]
-robot = [
-    { name = "av" },
-    { name = "datasets" },
-    { name = "deepdiff" },
-    { name = "jsonlines" },
-    { name = "pandas" },
-    { name = "pyarrow" },
-    { name = "pynput" },
-    { name = "pyserial" },
-    { name = "rerun-sdk" },
-    { name = "torchcodec", marker = "(platform_machine != 'aarch64' and platform_machine != 'arm64' and platform_machine != 'armv7l' and sys_platform == 'linux') or (platform_machine != 'x86_64' and sys_platform == 'darwin') or (sys_platform != 'darwin' and sys_platform != 'linux' and sys_platform != 'win32')" },
-]
 robstride = [
     { name = "python-can" },
 ]
@@ -2607,12 +2607,12 @@ requires-dist = [
     { name = "lerobot", extras = ["damiao"], marker = "extra == 'openarms'" },
     { name = "lerobot", extras = ["dataset"], marker = "extra == 'all'" },
     { name = "lerobot", extras = ["dataset"], marker = "extra == 'aloha'" },
+    { name = "lerobot", extras = ["dataset"], marker = "extra == 'core-scripts'" },
     { name = "lerobot", extras = ["dataset"], marker = "extra == 'dataset-viz'" },
     { name = "lerobot", extras = ["dataset"], marker = "extra == 'dev'" },
     { name = "lerobot", extras = ["dataset"], marker = "extra == 'libero'" },
     { name = "lerobot", extras = ["dataset"], marker = "extra == 'metaworld'" },
     { name = "lerobot", extras = ["dataset"], marker = "extra == 'pusht'" },
-    { name = "lerobot", extras = ["dataset"], marker = "extra == 'robot'" },
     { name = "lerobot", extras = ["dataset"], marker = "extra == 'test'" },
     { name = "lerobot", extras = ["dataset"], marker = "extra == 'training'" },
     { name = "lerobot", extras = ["dev"], marker = "extra == 'all'" },
@@ -2628,8 +2628,8 @@ requires-dist = [
     { name = "lerobot", extras = ["grpcio-dep"], marker = "extra == 'dev'" },
     { name = "lerobot", extras = ["grpcio-dep"], marker = "extra == 'hilserl'" },
     { name = "lerobot", extras = ["hardware"], marker = "extra == 'all'" },
+    { name = "lerobot", extras = ["hardware"], marker = "extra == 'core-scripts'" },
     { name = "lerobot", extras = ["hardware"], marker = "extra == 'dev'" },
-    { name = "lerobot", extras = ["hardware"], marker = "extra == 'robot'" },
     { name = "lerobot", extras = ["hardware"], marker = "extra == 'test'" },
     { name = "lerobot", extras = ["hilserl"], marker = "extra == 'all'" },
     { name = "lerobot", extras = ["hopejr"], marker = "extra == 'all'" },
@@ -2680,9 +2680,9 @@ requires-dist = [
     { name = "lerobot", extras = ["transformers-dep"], marker = "extra == 'xvla'" },
     { name = "lerobot", extras = ["video-benchmark"], marker = "extra == 'all'" },
     { name = "lerobot", extras = ["viz"], marker = "extra == 'all'" },
+    { name = "lerobot", extras = ["viz"], marker = "extra == 'core-scripts'" },
     { name = "lerobot", extras = ["viz"], marker = "extra == 'dataset-viz'" },
     { name = "lerobot", extras = ["viz"], marker = "extra == 'dev'" },
-    { name = "lerobot", extras = ["viz"], marker = "extra == 'robot'" },
     { name = "lerobot", extras = ["viz"], marker = "extra == 'test'" },
     { name = "lerobot", extras = ["wallx"], marker = "extra == 'all'" },
     { name = "lerobot", extras = ["xvla"], marker = "extra == 'all'" },
@@ -2740,7 +2740,7 @@ requires-dist = [
     { name = "transformers", marker = "extra == 'transformers-dep'", specifier = "==5.3.0" },
     { name = "wandb", marker = "extra == 'training'", specifier = ">=0.24.0,<0.25.0" },
 ]
-provides-extras = ["dataset", "training", "hardware", "viz", "build", "robot", "evaluation", "dataset-viz", "av-dep", "pygame-dep", "placo-dep", "transformers-dep", "grpcio-dep", "can-dep", "peft-dep", "scipy-dep", "diffusers-dep", "qwen-vl-utils-dep", "matplotlib-dep", "feetech", "dynamixel", "damiao", "robstride", "openarms", "gamepad", "hopejr", "lekiwi", "unitree-g1", "reachy2", "kinematics", "intelrealsense", "phone", "diffusion", "wallx", "pi", "smolvla", "multi-task-dit", "groot", "sarm", "xvla", "hilserl", "async", "peft", "dev", "test", "video-benchmark", "aloha", "pusht", "libero", "metaworld", "all"]
+provides-extras = ["dataset", "training", "hardware", "viz", "build", "core-scripts", "evaluation", "dataset-viz", "av-dep", "pygame-dep", "placo-dep", "transformers-dep", "grpcio-dep", "can-dep", "peft-dep", "scipy-dep", "diffusers-dep", "qwen-vl-utils-dep", "matplotlib-dep", "feetech", "dynamixel", "damiao", "robstride", "openarms", "gamepad", "hopejr", "lekiwi", "unitree-g1", "reachy2", "kinematics", "intelrealsense", "phone", "diffusion", "wallx", "pi", "smolvla", "multi-task-dit", "groot", "sarm", "xvla", "hilserl", "async", "peft", "dev", "test", "video-benchmark", "aloha", "pusht", "libero", "metaworld", "all"]
 
 [[package]]
 name = "librt"