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MolmoAct 2

MolmoAct 2 is Ai2’s open robotics foundation model for real-world manipulation, built to reason about actions in 3D and released with datasets, evaluation artifacts, and code for research use. It also integrates with Hugging Face’s LeRobot platform for embodied AI workflows.

MolmoAct 2

Open robotics foundation model for manipulation

MolmoAct 2 is Ai2’s open foundation model for real-world robot manipulation. It is positioned as a substantial upgrade to the original MolmoAct, with a focus on 3D action reasoning, open research artifacts, and practical deployment in physical environments.

The page says MolmoAct 2 can handle a range of real-world tasks out of the box without per-task fine-tuning, and that it runs up to 37x faster than its predecessor. Ai2 also released the MolmoAct 2-Bimanual YAM dataset, the updated VLA pipeline, and—after the May 28 update—the full code and training data behind the model for researchers to study, reproduce, and adapt.

What MolmoAct 2 provides

3D action reasoning

MolmoAct 2 is described as a foundation model for real-world robot manipulation, built to reason about an environment in 3D before it acts.

Reasoning plus action execution

Ai2 says the model uses a dedicated action expert and adaptive depth reasoning, which are intended to keep inference efficient while improving how the system plans actions.

Open training and evaluation artifacts

The release includes model weights, datasets, evaluation artifacts, and an updated VLA pipeline, so researchers can inspect and reproduce the system rather than only consume a hosted endpoint.

Code and training-data release

The May 28 update says the full code and training data are open, including fine-tuning scripts, every dataset used during training, evaluation rollouts, and the tokenizer training recipe.

LeRobot integration

Ai2 says MolmoAct 2 inference and training are integrated into Hugging Face’s LeRobot platform, making it easier to use within that ecosystem.

Large companion dataset

The release is paired with the MolmoAct 2-Bimanual YAM dataset, described as the largest open-source bimanual tabletop manipulation robotics dataset ever published, with over 720 hours of demonstrations.

Where MolmoAct 2 fits

  • 3D manipulation research

    Use the model for research on manipulation policies that need to reason about object position, depth, and action sequence in 3D space before acting.

  • Reproducibility and benchmarking

    Use the open datasets, evaluation artifacts, and code to reproduce the published system and compare new approaches against the baseline release.

  • Hardware or task adaptation

    Use the model as a starting point for adapting manipulation behavior to new robot hardware or different task settings, as Ai2 says the release is open for customization.

  • LeRobot-based experimentation

    Use the LeRobot integration to incorporate MolmoAct 2 into an existing Hugging Face-based robotics workflow without rebuilding the full stack.

Pros and Cons

Pros

  • Fully open release with weights, datasets, evaluation artifacts, and code for research use.
  • Designed to reason in 3D before acting, which is the core capability needed for manipulation tasks.
  • Can handle real-world tasks out of the box without per-task fine-tuning, according to the release.
  • The May 28 update adds broad reproducibility material, including fine-tuning scripts, training data, and evaluation rollouts.
  • Inference and training are integrated with Hugging Face’s LeRobot platform.

Cons

  • The page does not provide a full technical report in the collected text, so setup, deployment, and limitation details remain incomplete here.
  • The pricing page in the provided sources returns a 404, so there is no usable pricing or licensing detail beyond the open-release framing.
  • The public evidence is focused on manipulation and embodied reasoning; it does not show a broad general-robotics workflow or non-robotics use case.

FAQ

What is MolmoAct 2?

MolmoAct 2 is presented as a fully open robotics foundation model for real-world robot manipulation. The page says its weights, datasets, evaluation artifacts, and updated VLA pipeline are open for researchers to study and build on.

What kinds of tasks is it designed for?

The page says MolmoAct 2 can handle real-world tasks out of the box without per-task fine-tuning and is designed to reason in 3D before acting. It is positioned as a model for robot manipulation rather than a general-purpose chat or vision product.

What is available to the public?

Ai2 says the model, the MolmoAct 2-Bimanual YAM dataset, and the updated VLA pipeline are available for researchers. The May 28 update also says the code release includes fine-tuning scripts, training data, evaluation rollouts, and the tokenizer training recipe.

Does MolmoAct 2 have public pricing?

The source does not list commercial pricing for MolmoAct 2. The pricing page linked in the collected sources returns a 404, so the available evidence only supports that the project is released openly for research use.

Can it fit into an existing robotics workflow?

Ai2 says MolmoAct 2 inference and training are integrated into Hugging Face’s LeRobot platform. The page also says the model is open to researchers who want to adapt it to new hardware or different tasks.

Quick Facts

Category
Robotics foundation model
Primary use
Real-world robot manipulation
Publisher
Ai2 (Allen Institute for Artificial Intelligence)
Related dataset
MolmoAct 2-Bimanual YAM
Open artifacts
Weights, datasets, evaluation artifacts, code, training data
Platform integration
Hugging Face LeRobot