Hacking an LLM's Personality with Representation Engineering

Papers & Resources [Persona Vectors: Monitoring and Controlling Character Traits in Language Models](https://arxiv.org/abs/2507.21509) = Interpretability [Blog post](https://www.anthropic.com/research/pe...) [Code Repo](https://github.com/safety-research/pe...) [Anthropic Thread](https://x.com/AnthropicAI/status/1951...) [Anthropic Hiring](https://x.com/Jack_W_Lindsey/status/1...) [A Simple but Tough-to-Beat Baseline for Sentence Embeddings](https://openreview.net/pdf?id=SyK00v5xx) [Improving Reasoning Performance in Large Language Models via Representation Engineering](https://arxiv.org/abs/2504.19483) [Poster: #246 ICLR](https://iclr.cc/virtual/2025/poster/3...) Control vectors derived from positive and negative reasoning outcomes [Learning without training: The implicit dynamics of in-context learning](https://arxiv.org/abs/2507.16003) [Author Tweet](https://x.com/mikemunnster/status/194...) Earlier work : [Why Can GPT Learn In-Context? Language Models Implicitly Perform Gradient Descent as Meta-Optimizers](https://arxiv.org/abs/2212.10559) [It's Owl in the Numbers: Token Entanglement in Subliminal Learning](https://owls.baulab.info/) [Colab (as in the video)](https://colab.research.google.com/dri...) Blurb Is it possible to perform surgery on an LLM's brain? In this video, we dive deep into one of the most exciting new frontiers in AI research: Representation Engineering, and specifically Anthropic's work on "Persona Vectors." We've all struggled with prompting LLMs to get them to behave exactly as we want, fighting against baked-in behaviors like sycophancy, evasiveness, or even hallucination. But what if we could stop treating the model like a black box and instead edit its internal states directly? We'll break down the papers to understand how researchers are identifying and manipulating the very vectors that control these complex personality traits. By the end of this video, you'll understand: The core mechanism behind Anthropic's "Persona Vectors" How this technique relates (sometimes tangentially) to other research works The potential this unlocks for creating safer, more reliable, and precisely controlled AI systems. ABOUT THE CHANNEL My channel is for "The AI Builder": the developer, tinkerer, and hands-on enthusiast. We go beyond the headlines to understand the mechanisms behind the latest research, empowering you to build the future. From the Lab to Your Laptop. SOCIALS https://github.com/mdda   / martinandrews   https://x.com/mdda123 #AI #LLM #MachineLearning #Research #LatentSpace #AIExplained #PersonaVector #Anthropic #Colab