Codex Just Became Unlimited! Also GPT 5.6 Is Actually Really…
Last Updated on July 16, 2026 by Editorial Team
Author(s): Caspar Bannink – AI Engineer
Originally published on Towards AI.
Codex Just Became Unlimited! Also GPT 5.6 Is Actually Really…
Amazing. Well, it depends on who you ask. In my opinion, GPT-5.6 is my favorite release yet.

The author says Codex is effectively more usable now because the old five-hour cap is gone for their account, replaced by a weekly limit that better fits long coding sessions. They argue OpenAI’s GPT-5.6 lineup is best understood as a family designed for routing by cost and capability: Sol (premium), Terra (a cheaper GPT-5.5 replacement), and Luna (lowest-cost, high-volume option), while GPT-5.4 mini remains the budget choice and Claude models still have their place. They break down how token price isn’t the same as token efficiency or real cost per completed task, using Artificial Analysis evaluations and benchmark comparisons to show where each model sits on intelligence-versus-cost tradeoffs, including coding-agent and Intelligence Index results. Finally, they provide practical routing guidance—use Terra first for many agent tasks formerly done with GPT-5.5, pick Sol when higher success probability justifies extra cost, keep mini for bounded lower-risk work, and use top-end competitors selectively—concluding that the improvement is about having better cheaper capability steps within the loop rather than finding a single universal winner.
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