MolmoAct Action Reasoning Models that can Reason in Space

Reasoning is central to purposeful action. Today we introduce MolmoAct — a fully open Action Reasoning Model (ARM) for robotics. Grounded in large-scale pre-training with action reasoning data, every predicted action is interpretable and user-steerable via visual trace. We are

Introducing MolmoAct Our Action Reasoning Model that can Reason in Space (1/)🧵⬇️

Ai2 unveils MolmoAct: Open-source robotics system reasons in 3D and adjusts on the fly geekwire.com/2025/ai2-unvei…

Ai2's commitment to **fully openness** is serious and here comes another one! Checkout MolmoAct, great action reasoning model that could benefit the entire robotics field! AMAZING project led by my colleagues Jiafei Duan Jason Lee Haoquan Fang Ranjay Krishna

This to me really feels like how robot foundation models "should" work. i like that it can autoregressively predict depth tokens, lift to 2.5d, and use this for reasoning - it feels like a true robotics analogue of modern reasoning LLMs. Really exciting work.

Most AI models still think in words. People, without even noticing, think with our bodies, planning how to move, grasp, and use things around us. MolmoAct brings that to robotics: reasoning in space before acting. This is how we will get to the GPT-moment for robotics.

We will release all artifacts used in creating MolmoAct (data, training code, evaluations, intermediate checkpoints), furthering our commitment to open-source AI development and reproducibility. Please stay tuned for the following repo, and feel free to star or repost ✨

Nice talk with Chris Matthieu on our recent project #MolmoAct 🙌 #RealSense is really one of the key components that enables robots to “see” in our development stack.