On July 6, Thibault Sottiaux, the head of core products at OpenAI, confirmed on social media that the Ultra version of the next-generation flagship model GPT-5.6 Sol will integrate with Codex. Previously, users complained that OpenAI's decision not to include GPT-5.5 Pro in Codex was a significant oversight. If GPT-5.6 Ultra is integrated, developers may not even need to pay for Claude anymore; Sottiaux subsequently confirmed that the Ultra version is indeed planned for Codex.
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