OpenAI ships GPT-5.6 to GA, with Sol topping the Codex coding index at a third of Fable 5's cost

OpenAI moved GPT-5.6 — Sol, Terra, and Luna — to general availability across ChatGPT, the API, and Codex on July 9, ending a two-week preview that followed a US Commerce Department security review. Sol trails Claude Fable 5 by one point on the Intelligence Index but tops the Coding Agent Index at 80 while costing about $1.04 per task, roughly a third of Fable 5's price — resetting the coding price-performance frontier, with Terra and Luna undercutting Sol by a further 50% and 80%.

Source: openai.com ↗