GPT-5.6 Sol is OpenAI's flagship everyday assistant for finishing real work—computer use, long tool chains, and messy multi-step help. Our tests put it at or near the top overall: unmatched helpfulness, instruction following, and comprehension, with strong natural empathy. Creative writing still pays the reasoning tax—compressed "caveman" internal scratchpads keep prose flatter than Claude Fable or the old GPT-4.5 peak—but it remains the clearest #1/#2 pick when you want an assistant that actually completes the job. Scored at cost-efficient medium/high reasoning.