NVIDIA Introduces Molt: PyTorch Framework for Agentic RL

Jian Hu, Huiying Li, Hao Zhang, Binfeng Xu, Yifan Zhang, Shaokun Zhang, Hemil Desai, Michael Demoret, Pavlo Molchanov, Jan Kautz, Yi Dong· July 27, 2026 View original

Summary

NVIDIA's Molt is a new PyTorch-native training framework designed for agentic reinforcement learning, offering a compact and clean codebase that simplifies algorithm modification and ensures consistent training on self-generated tokens. It achieves performance comparable to state-of-the-art Megatron-based stacks while being open-source.

Developing and iterating on agentic reinforcement learning (RL) algorithms often involves significant overhead due to complex interactions between trainers, distributed backends, and rollout mechanisms in existing frameworks. This complexity can hinder researchers' ability to rapidly experiment and modify algorithms. NVIDIA has introduced Molt, a new PyTorch-native training framework specifically designed to address these challenges. Molt aims to provide a highly compact and clean codebase, making it easier for researchers to understand and modify the entire algorithm flow. It treats the agent as a standard program and uses a single asynchronous loop to train multimodal and mixture-of-experts policies. A key feature is its guarantee that training only occurs on tokens generated by the agent itself, ensuring consistency in tokens, policy versions, and model semantics. Despite its lean design, Molt does not compromise on performance. Benchmarking against a state-of-the-art Megatron-based stack under matched asynchronous protocols, Molt demonstrated statistically comparable performance. The framework is open-source and includes recipes and containers, making it accessible for researchers and developers to adopt and integrate into their RL workflows.

Why it matters

RL researchers and engineers can use Molt to accelerate the development and iteration of complex agentic AI systems, reducing the overhead associated with framework complexities and enabling faster experimentation.

How to implement this in your domain

  1. 1Explore the Molt GitHub repository to understand its architecture and example recipes.
  2. 2Download and set up Molt in a development environment to test its core functionalities.
  3. 3Migrate a small-scale agentic reinforcement learning project to Molt to evaluate its ease of use and performance.
  4. 4Contribute to the Molt open-source community by providing feedback or developing new features.
  5. 5Benchmark Molt against existing RL frameworks for specific use cases to assess its efficiency and scalability.

Who benefits

AI/ML DevelopmentRoboticsGamingAutonomous SystemsResearch & Development

Key takeaways

  • Molt is a new PyTorch-native framework for agentic RL.
  • It simplifies algorithm modification with a compact codebase.
  • Molt ensures consistent training on self-generated tokens.
  • It offers performance comparable to state-of-the-art stacks and is open-source.

Original post by Jian Hu, Huiying Li, Hao Zhang, Binfeng Xu, Yifan Zhang, Shaokun Zhang, Hemil Desai, Michael Demoret, Pavlo Molchanov, Jan Kautz, Yi Dong

"arXiv:2607.21653v1 Announce Type: new Abstract: Agentic reinforcement learning research is constant algorithm modification, new estimators, new pipeline stages, new rollout schemes, and in mainstream frameworks each change threads through layers of trainer, distributed backend, a…"

View on X

Originally posted by Jian Hu, Huiying Li, Hao Zhang, Binfeng Xu, Yifan Zhang, Shaokun Zhang, Hemil Desai, Michael Demoret, Pavlo Molchanov, Jan Kautz, Yi Dong on X · view source

Want to go deeper?

Turn these trends into skills with Learnijoy's hands-on AI & tech courses.

Explore courses