OpenAI’s new GPT-5.6 Sol model is giving Anthropic’s Claude Mythos a run for its money, especially in agentic coding and cybersecurity. Sol boasts better token efficiency and matches or beats Mythos in several benchmarks. However, access to Sol is currently limited to select partners due to US government restrictions, which OpenAI claims is unsustainable and hurts developers and businesses. Why it matters: this development signals a significant shift in the AI landscape as companies navigate government regulations and push the boundaries of AI capabilities.