Hacker News
OpenAI Unveils GPT-5.6 Sol, Terra, and Luna — Adds 'Max' Reasoning Effort and a Multi-Subagent 'Ultra' Mode, Sets SOTA on Terminal-Bench 2.1
On June 26 OpenAI previewed a three-model GPT-5.6 family: Sol (flagship, $5.00/$30.00 per M input/output tokens — same as GPT-5.5), Terra (GPT-5.5-class at ~2x cheaper), and Luna (cheapest/fastest). Sol sets a new state of the art on Terminal-Bench 2.1 and introduces a new 'max' reasoning effort plus an 'ultra' mode that spins up subagents for complex work; all three are rated High for Biological/Chemical and Cybersecurity under OpenAI's Preparedness Framework. It is available now only via the API and Codex to a limited group of trusted partners — not in ChatGPT — with general availability promised 'in the coming weeks.'
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