Youtu-LLM: The Lightweight Autonomous Agent That Outthinks Larger Models

Youtu-LLM: When a 2B Model Learns to Think and Act What makes Youtu-LLM fundamentally different from other lightweight language models? It’s the first sub-2B model trained from scratch to be an autonomous agent, not just a chatbot—embedding planning, reflection, and tool-use directly into its neural architecture through 340 billion tokens of specialized trajectory data. In the rush to make large language models smaller, we’ve been solving the wrong problem. For two years, the dominant approach has been distillation: take a massive model like GPT-4, shrink it, and hope the magic survives. The result? Models that talk fluently but break down …