* docs(benchmarks): add benchmark integration guide and standardize benchmark docs Add a comprehensive guide for adding new benchmarks to LeRobot, and refactor the existing LIBERO and Meta-World docs to follow the new standardized template. Made-with: Cursor * refactor(envs): move dispatch logic from factory into EnvConfig subclasses Replace hardcoded if/elif chains in factory.py with create_envs() and get_env_processors() methods on EnvConfig. New benchmarks now only need to register a config subclass — no factory.py edits required. Net -23 lines: factory.py shrinks from ~200 to ~70 lines of logic. Made-with: Cursor * docs(benchmarks): clean up adding-benchmarks guide for clarity Rewrite for simpler language, better structure, and easier navigation. Move quick-reference table to the top, fold eval explanation into architecture section, condense the doc template to a bulleted outline. Made-with: Cursor * fix link * fix task count * fix: enable SmolVLA eval on LIBERO with custom camera mappings - Thread camera_name_mapping from LiberoEnv config through to gym envs - Sync features_map with camera_name_mapping in LiberoEnv.__post_init__ - Fix render() to use first available camera instead of hardcoded "image" - Handle non-dict final_info in rollout by falling back to info["is_success"] - Add use_peft legacy field to SmolVLAConfig for checkpoint compat - Add defaults to GR00TN15Config init=False fields for transformers 5.3 Made-with: Cursor * fix: use direct AutoresetMode import for gymnasium compat Made-with: Cursor * fix: handle gymnasium < 1.0 without AutoresetMode Made-with: Cursor * refactor: revert policy changes, keep env-only camera mapping fixes - Revert GR00T N1.5 default_factory/default changes (transformers compat) - Revert SmolVLA use_peft legacy field - Apply ruff formatting fixes - camera_name_mapping stays entirely in env/eval layer (no policy changes) Made-with: Cursor * Update docs/source/env_processor.mdx Co-authored-by: Khalil Meftah <khalil.meftah@huggingface.co> Signed-off-by: Pepijn <138571049+pkooij@users.noreply.github.com> * feat(envs): lazy env init + AsyncVectorEnv as default for n_envs > 1 LiberoEnv and MetaworldEnv previously allocated GPU resources (EGL context, OpenGL framebuffer) in __init__, before AsyncVectorEnv's fork(). Worker processes inherited stale GPU handles, causing EGL_BAD_CONTEXT crashes on first render. Fix: defer OffScreenRenderEnv / MT1 construction to _ensure_env(), called on first reset() or step() inside the worker subprocess. Each worker creates its own clean context after fork(). Also fixes lerobot_eval.py:170 (add_envs_task TODO): replace with env.call("task") which works with both SyncVectorEnv and AsyncVectorEnv. AsyncVectorEnv is now the default for n_envs > 1; auto-downgraded to SyncVectorEnv when n_envs=1 (no benefit, less overhead). Expected speedup: ~15-20x for LIBERO Spatial with batch_size=50. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> * fix: close envs between tasks to prevent worker process accumulation eval_policy_all never closed environments after each task completed, causing AsyncVectorEnv worker processes to accumulate (N_tasks × n_envs). This led to OOM, BrokenPipeError and EOFError on multi-task benchmarks. Also fixes: - AsyncVectorEnv compat in envs/utils.py (use get_attr/call instead of .envs) - Tuple task handling in tokenizer_processor and lerobot_eval - _LazyAsyncVectorEnv for deferred worker spawning in LIBERO Made-with: Cursor * fix(eval): use task_description instead of task for language conditioning env.call("task") returns the LIBERO task name with underscores (e.g. "pick_up_the_black_bowl_...") instead of the natural language description ("pick up the black bowl ..."). The VLM tokenizes these completely differently, causing 0.0 reward across all episodes. Made-with: Cursor * docs: update adding_benchmarks for async env changes - Replace add_envs_task reference with env.call("task_description") - Update use_async_envs default to True - Add note about lazy GPU init for AsyncVectorEnv compatibility Made-with: Cursor * feat(eval): batch_size=auto + faster env loading - batch_size=0 (default) auto-tunes based on CPU cores, capped by n_episodes and 64. Removes the need for users to guess the right value. The old batch_size > n_episodes error is replaced by silently clamping to n_episodes. - _LazyAsyncVectorEnv accepts pre-computed spaces so only one temp env is created per suite (not per task). For libero_spatial (10 tasks) this avoids 9 redundant LiberoEnv instantiations during env setup. Made-with: Cursor * docs: add evaluation guide and update benchmarks doc - New docs/source/evaluation.mdx covering lerobot-eval usage, batch_size auto-tuning, AsyncVectorEnv performance, tuning tips, output format, multi-task evaluation, and programmatic usage. - Add evaluation page to _toctree.yml under Benchmarks section. - Update adding_benchmarks.mdx to reference batch_size auto default and link to the evaluation guide. Made-with: Cursor * docs(evaluation): remove benchmark table, rename section header Made-with: Cursor * perf(eval): shared memory, observation passthrough, task prefetch - AsyncVectorEnv now uses shared_memory=True for zero-copy observation transfer - LiberoEnvConfig.gym_kwargs passes observation_height/width to the env - eval_policy_all prefetches next task's workers while current task runs Made-with: Cursor * style: ruff format Made-with: Cursor * chore: revert env_processor.mdx changes (not part of this PR) Made-with: Cursor * ci(benchmarks): add isolated integration tests for libero and metaworld Each benchmark gets its own Docker image (lerobot[libero] / lerobot[metaworld] only) so incompatible dep trees cannot collide. A 1-episode smoke eval runs per benchmark on GPU runners. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> * ci(benchmarks): pin action hashes and use uv sync --locked Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> * ci(benchmarks): trigger only on envs/ or lerobot_eval.py changes Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> * fix(ci): set LIBERO_DATA_FOLDER to bypass interactive stdin prompt libero/__init__.py calls input() to ask about a custom dataset path, which raises EOFError when stdin is closed inside Docker. Setting LIBERO_DATA_FOLDER skips the prompt entirely. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> * docs(benchmarks): add CI smoke test step to adding_benchmarks guide Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> * fix(ci): pre-create libero config in Dockerfile to bypass stdin prompt libero/__init__.py calls input() when ~/.libero/config.yaml is missing. We write the config at image build time (without importing libero) so the prompt never fires at runtime. Also trigger CI on pyproject.toml changes. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> * fix(ci): use shell to create libero config instead of multiline python -c The multiline RUN python -c "..." was being parsed as Dockerfile instructions. Use printf to write ~/.libero/config.yaml directly. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> * fix(ci): point libero config to bundled package init_files The config was pointing to /tmp/libero_init which doesn't exist. Use importlib.util.find_spec to locate the hf-libero package directory and write paths to the actual bundled bddl_files/init_files/assets. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> * fix(ci): add smolvla extra to benchmark Dockerfiles num2words (required by SmolVLM processor) is declared in lerobot[smolvla], not lerobot[libero/metaworld]. Install both extras together. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> * fix(eval): render_frame covers _LazyAsyncVectorEnv isinstance(env, AsyncVectorEnv) silently skipped _LazyAsyncVectorEnv, causing video rendering to produce no frames on the default async path. Switch to hasattr(env, "call") so any async-compatible env (including _LazyAsyncVectorEnv) hits the call("render") branch. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> * refactor(envs): remove unused _get_sub_env_attr helper _get_sub_env_attr was defined but never called anywhere in the codebase. _sub_env_has_attr (its sibling) is kept — it is actively used in utils.py. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> * chore: apply prettier formatting to docs Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> * docs(env_processor): remove deprecated add_envs_task from pipeline example add_envs_task is replaced by env.call("task_description") in this PR. Remove it from the pipeline walkthrough and renumber the steps (8→7). Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> * refactor(envs): remove __del__ from _LazyAsyncVectorEnv __del__ is unreliable as a cleanup mechanism. close() is already called explicitly in the eval loop's finally block, so the finalizer is redundant. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> * fix(eval): prefetch next task's workers after close to avoid GPU memory overlap Previously, next task's AsyncVectorEnv workers were spawned while the current task was still running, causing both tasks' GPU contexts to coexist. Moving the prefetch start into the finally block (after env.close()) ensures workers for task N+1 only spin up once task N has released GPU memory. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> * refactor(envs): move _LazyAsyncVectorEnv to utils and apply to metaworld _LazyAsyncVectorEnv lived in libero.py but metaworld had the same OOM problem: all tasks' AsyncVectorEnv workers were spawned eagerly, wasting GPU memory for tasks not yet running. Move the class to envs/utils.py so both environments share it, then apply the same is_async + lazy wrapping pattern in create_metaworld_envs. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> * chore: remove out-of-scope benchmark/CI/docs files from PR Benchmark CI workflow, Dockerfiles, benchmark docs, evaluation smoke-test doc, and dispatch tests belong in a separate PR. Scope this PR to the async env init changes only. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> * chore: restore adding_benchmarks + test_dispatch, drop env_processor changes - Restore docs/source/adding_benchmarks.mdx (belongs in this PR) - Restore tests/envs/test_dispatch.py (belongs in this PR) - Revert docs/source/env_processor.mdx to main (out of scope for this PR) Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> * docs(adding_benchmarks): remove CI smoke test step (coming in separate PR) Step 7 (Dockerfile + benchmark_tests.yml CI job) and its table rows are out of scope for this PR. The CI infrastructure will be added on top in a follow-up PR. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> * refactor(envs): remove unused add_envs_task Replaced by env.call("task_description") in lerobot_eval.py. No callers remain in the codebase. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> * style: fix prettier formatting in env_processor.mdx Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> * fix(eval): catch AttributeError and NotImplementedError explicitly for task description Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> * fix(envs): use forkserver context and close envs in test to prevent deadlock AsyncVectorEnv with default fork context leaks worker processes between test_policy parametrized cases; subsequent env creation deadlocks because new forked workers inherit stale pipe FDs from previous test's leaked workers. - configs.py: pass context="forkserver" to AsyncVectorEnv (matches _LazyAsyncVectorEnv) - test_policies.py: call close_envs(envs) at end of test_policy to clean up workers Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> * fix(envs): default use_async_envs=False in create_envs and make_env Tests that call make_env(n_envs=2) without passing use_async_envs were getting AsyncVectorEnv, whose forked workers can't resolve gym namespaces registered at runtime. Default to False (sync) so existing tests pass. lerobot_eval.py explicitly passes cfg.eval.use_async_envs, so the CLI async behaviour (controlled by EvalConfig.use_async_envs) is unchanged. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com> --------- Signed-off-by: Pepijn <138571049+pkooij@users.noreply.github.com> Co-authored-by: Khalil Meftah <khalil.meftah@huggingface.co> Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
LeRobot aims to provide models, datasets, and tools for real-world robotics in PyTorch. The goal is to lower the barrier to entry so that everyone can contribute to and benefit from shared datasets and pretrained models.
🤗 A hardware-agnostic, Python-native interface that standardizes control across diverse platforms, from low-cost arms (SO-100) to humanoids.
🤗 A standardized, scalable LeRobotDataset format (Parquet + MP4 or images) hosted on the Hugging Face Hub, enabling efficient storage, streaming and visualization of massive robotic datasets.
🤗 State-of-the-art policies that have been shown to transfer to the real-world ready for training and deployment.
🤗 Comprehensive support for the open-source ecosystem to democratize physical AI.
Quick Start
LeRobot can be installed directly from PyPI.
pip install lerobot
lerobot-info
Important
For detailed installation guide, please see the Installation Documentation.
Robots & Control
LeRobot provides a unified Robot class interface that decouples control logic from hardware specifics. It supports a wide range of robots and teleoperation devices.
from lerobot.robots.myrobot import MyRobot
# Connect to a robot
robot = MyRobot(config=...)
robot.connect()
# Read observation and send action
obs = robot.get_observation()
action = model.select_action(obs)
robot.send_action(action)
Supported Hardware: SO100, LeKiwi, Koch, HopeJR, OMX, EarthRover, Reachy2, Gamepads, Keyboards, Phones, OpenARM, Unitree G1.
While these devices are natively integrated into the LeRobot codebase, the library is designed to be extensible. You can easily implement the Robot interface to utilize LeRobot's data collection, training, and visualization tools for your own custom robot.
For detailed hardware setup guides, see the Hardware Documentation.
LeRobot Dataset
To solve the data fragmentation problem in robotics, we utilize the LeRobotDataset format.
- Structure: Synchronized MP4 videos (or images) for vision and Parquet files for state/action data.
- HF Hub Integration: Explore thousands of robotics datasets on the Hugging Face Hub.
- Tools: Seamlessly delete episodes, split by indices/fractions, add/remove features, and merge multiple datasets.
from lerobot.datasets.lerobot_dataset import LeRobotDataset
# Load a dataset from the Hub
dataset = LeRobotDataset("lerobot/aloha_mobile_cabinet")
# Access data (automatically handles video decoding)
episode_index=0
print(f"{dataset[episode_index]['action'].shape=}\n")
Learn more about it in the LeRobotDataset Documentation
SoTA Models
LeRobot implements state-of-the-art policies in pure PyTorch, covering Imitation Learning, Reinforcement Learning, and Vision-Language-Action (VLA) models, with more coming soon. It also provides you with the tools to instrument and inspect your training process.
Training a policy is as simple as running a script configuration:
lerobot-train \
--policy=act \
--dataset.repo_id=lerobot/aloha_mobile_cabinet
| Category | Models |
|---|---|
| Imitation Learning | ACT, Diffusion, VQ-BeT, Multitask DiT Policy |
| Reinforcement Learning | HIL-SERL, TDMPC & QC-FQL (coming soon) |
| VLAs Models | Pi0Fast, Pi0.5, GR00T N1.5, SmolVLA, XVLA |
Similarly to the hardware, you can easily implement your own policy & leverage LeRobot's data collection, training, and visualization tools, and share your model to the HF Hub
For detailed policy setup guides, see the Policy Documentation.
Inference & Evaluation
Evaluate your policies in simulation or on real hardware using the unified evaluation script. LeRobot supports standard benchmarks like LIBERO, MetaWorld and more to come.
# Evaluate a policy on the LIBERO benchmark
lerobot-eval \
--policy.path=lerobot/pi0_libero_finetuned \
--env.type=libero \
--env.task=libero_object \
--eval.n_episodes=10
Learn how to implement your own simulation environment or benchmark and distribute it from the HF Hub by following the EnvHub Documentation
Resources
- Documentation: The complete guide to tutorials & API.
- Chinese Tutorials: LeRobot+SO-ARM101中文教程-同济子豪兄 Detailed doc for assembling, teleoperate, dataset, train, deploy. Verified by Seed Studio and 5 global hackathon players.
- Discord: Join the
LeRobotserver to discuss with the community. - X: Follow us on X to stay up-to-date with the latest developments.
- Robot Learning Tutorial: A free, hands-on course to learn robot learning using LeRobot.
Citation
If you use LeRobot in your project, please cite the GitHub repository to acknowledge the ongoing development and contributors:
@misc{cadene2024lerobot,
author = {Cadene, Remi and Alibert, Simon and Soare, Alexander and Gallouedec, Quentin and Zouitine, Adil and Palma, Steven and Kooijmans, Pepijn and Aractingi, Michel and Shukor, Mustafa and Aubakirova, Dana and Russi, Martino and Capuano, Francesco and Pascal, Caroline and Choghari, Jade and Moss, Jess and Wolf, Thomas},
title = {LeRobot: State-of-the-art Machine Learning for Real-World Robotics in Pytorch},
howpublished = "\url{https://github.com/huggingface/lerobot}",
year = {2024}
}
If you are referencing our research or the academic paper, please also cite our ICLR publication:
ICLR 2026 Paper
@inproceedings{cadenelerobot,
title={LeRobot: An Open-Source Library for End-to-End Robot Learning},
author={Cadene, Remi and Alibert, Simon and Capuano, Francesco and Aractingi, Michel and Zouitine, Adil and Kooijmans, Pepijn and Choghari, Jade and Russi, Martino and Pascal, Caroline and Palma, Steven and Shukor, Mustafa and Moss, Jess and Soare, Alexander and Aubakirova, Dana and Lhoest, Quentin and Gallou\'edec, Quentin and Wolf, Thomas},
booktitle={The Fourteenth International Conference on Learning Representations},
year={2026},
url={https://arxiv.org/abs/2602.22818}
}
Contribute
We welcome contributions from everyone in the community! To get started, please read our CONTRIBUTING.md guide. Whether you're adding a new feature, improving documentation, or fixing a bug, your help and feedback are invaluable. We're incredibly excited about the future of open-source robotics and can't wait to work with you on what's next—thank you for your support!


