Code World Model

Updated: 2026-09-24

Source

Code World Model is Meta's 32 billion parameter language model. It simulates execution of Python functions and reproduces agentic interactions in a Bash environment. It does more than predict the next line of code. It thinks ahead, simulates, and plans the way a human would. Listed scores are 68.6% on LiveCodeBench v5, 76% on AIME24, and 65.8% on SweBench Verified with test-time scaling. Linked resources include the tech report, model weights, Hugging Face checkpoints, and inference code.

Overview

  • Code World Model (CWM): Meta's 32-billion-parameter language model
  • It does more than predict the next line of code:
    • Simulates the execution of Python functions
    • Reproduces agentic interactions in a Bash environment
  • Significance: AI that doesn't just write code but also thinks ahead, simulates, and plans the way a human would

Results

  • 68.6% on LiveCodeBench v5
  • 76% on AIME24
  • 65.8% on SweBench Verified (with test-time scaling)

Applications and Potential

  • Test how a world model improves code generation
  • Build AI agents that can reason and plan
  • Bring coding AI closer to how humans actually think
  • Open up an "open lab" for the research community

Other World Models

  • A self-supervised world model trained on video, enabling zero-shot robot control and visual understanding

Resources

See also: LLM Overview · Coding Agents