OpenAI 出了三个新模型 Sol、Terra、Luna，Terra 和 GPT-5.5 差不多但便宜一半，Luna 超低价。还改了缓存计费规则，省钱又灵活。
OpenAI 发布 GPT-5.6 系列有限预览，包括旗舰模型 Sol、平衡模型 Terra 和快速廉价模型 Luna。Terra 性能与 GPT-5.5 相当，但成本降低 2 倍，输入每百万 tokens 仅 $2.50。Luna 为最低价选项，输入每百万 tokens $1。该系列引入可预测的提示缓存，支持显式缓存断点和 30 分钟最短缓存生命周期，缓存写入按 1.25 倍计费，读取享 90% 折扣。OpenAI 计划未来几周全面开放，并应美国政府要求先向可信伙伴提供预览。
Quoting OpenAI
We're beginning a limited preview of the GPT‑5.6 series: Sol, our flagship model; Terra, a balanced model for everyday work; and Luna, a fast and affordable model. Terra has competitive performance to GPT‑5.5 while being 2x cheaper and Luna brings strong capability at our lowest cost. [...] We believe in broad access, and we plan to make GPT‑5.6 Sol, Terra, and Luna generally available in the coming weeks. As part of our ongoing engagement with the U.S. government, we previewed our plans and the models’ capabilities ahead of today’s launch. At their request, we are starting with a limited preview for a small group of trusted partners whose participation has been shared with the government, before releasing more broadly. [...] GPT‑5.6 is priced per 1M tokens across three model sizes: Sol is $5 input / $30 output; Terra is $2.50 input / $15 output; and Luna is $1 input / $6 output. GPT‑5.6 also introduces more predictable prompt caching, including support for explicit cache breakpoints and a 30-minute minimum cache life. For GPT‑5.6 and later models, cache writes are billed at 1.25x the model’s uncached input rate, while cache reads continue to receive the 90% cached-input discount. — OpenAI , Previewing GPT‑5.6 Sol: a next-generation model Tags: gpt , generative-ai , ai-security-research , openai , llms , llm-release , llm-pricing