OpenAI releases the GPT-5.6 model family, GPT-5.6 Sol, Terra, and Luna, in its API

OpenAI's API changelog records that on July 9, 2026 it released the GPT-5.6 model family: GPT-5.6 Sol for frontier capability, GPT-5.6 Terra for a balance of intelligence and cost, and GPT-5.6 Luna for efficient, high-volume workloads. The entry says the gpt-5.6 alias routes requests to gpt-5.6-sol, and it lists the Responses, Chat Completions, and Batch endpoints. It also says GPT-5.6 adds Programmatic Tool Calling, explicit prompt caching controls, persisted reasoning, max reasoning effort, and Pro mode, with Multi-agent orchestration in beta for the Responses API. The changelog describes hosted models offered through OpenAI's API; it does not describe a release of model weights. USASI has not tested these models.1

USASI. (2026, October 13). OpenAI releases the GPT-5.6 model family, GPT-5.6 Sol, Terra, and Luna, in its API. United States of America Superintelligence. https://unitedstatesofamericasuperintelligence.com/news/openai-releases-gpt-5-6-model-family/

@misc{usasi_news_openai_releases_gpt_5_6_model_family,
  author = {{USASI}},
  title = {OpenAI releases the GPT-5.6 model family, GPT-5.6 Sol, Terra, and Luna, in its API},
  year = {2026},
  month = oct,
  howpublished = {\url{https://unitedstatesofamericasuperintelligence.com/news/openai-releases-gpt-5-6-model-family/}},
  note = {United States of America Superintelligence. Last updated 2026-10-13}
}