Researchers have found that large language models (LLMs) can read and write neural network weights, allowing them to understand and modify the behavior of other models. This capability, called Weight-Space Programming, enables LLMs to identify issues in a model's weights and fix them, or even write new weights from scratch. The researchers demonstrated this ability using the LLM Astra, which was able to improve the performance of a language model on a math task and write new weights for a game-playing model. This discovery has potential implications for the development of more advanced AI models.