OpenAI: Launching limited preview of the next generation model GPT-5.6 series, with Sol being the strongest.

OpenAI has announced that it has launched a limited preview of the GPT-5.6 series. This series includes the flagship model Sol, the balanced model Terra for daily work, and the fast and cost-effective model Luna. Terra performs similarly to GPT-5.5 but at half the cost, while Luna offers powerful capabilities at the lowest cost. GPT-5.6 Sol is equipped with the company's strongest security system to date, enhancing protection against high-risk activities, sensitive network requests, and repeated abusive behavior. The company spent several weeks searching for system vulnerabilities, conducting stress tests to enhance its ability to withstand real-world attacks. OpenAI plans to fully open GPT-5.6 Sol, Terra, and Luna in the coming weeks. As part of their ongoing communication with the US government, OpenAI presented their release plans and the models' capabilities to the government before the Friday release. GPT-5.6 Sol is their most powerful model to date.