Arena CEO Reveals GPT-5.6 Sol as His Favorite Underrated AI Model
Yannis Angelopoulos, the CEO of LMSYS Chatbot Arena, shared that his preferred, underrated AI model is OpenAI's GPT-5.6 Sol. He noted that while it might not top standard public leaderboards, it is highly favored by experts. This highlight suggests that public leaderboard rankings may not fully capture a model's utility for expert-level tasks. It emphasizes the gap between general crowd-sourced benchmarks and specialized, professional use cases. GPT-5.6 Sol is OpenAI's flagship model designed for complex reasoning, coding, and agentic workflows. It features a 1.05-million-token context window and supports up to 128k output tokens.
## BACKGROUND
LMSYS Chatbot Arena is a popular open-source benchmarking platform that evaluates large language models (LLMs) through anonymous, randomized pairwise battles. While it provides a robust crowd-sourced ranking, expert preferences often diverge due to the specific, highly complex demands of professional workflows.