@thsottiaux: We found and fixed two issues that could explain this degradation of the capability of GPT-5.5 in Codex over the last ~…
Summary
GPT-5.5 experienced capability degradation in Codex over approximately 48 hours. Two issues were found and fixed; usage limits will be reset after monitoring confirms full recovery.
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We found and fixed two issues that could explain this degradation of the capability of GPT-5.5 in Codex over the last ~ 48 hours.
We are monitoring over the coming hours to fully confirm and I will reset usage limits this evening.
Apologies and now is the time for /fast maxxing.
Tibo (@thsottiaux): Codex team is aware of reports of GPT-5.5 performing worse for some users and investigating. We don’t have anything conclusive yet and systems are healthy but we will share updates as we go.
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Codex usage limits have been reset across all paid plans after fixes for issues that degraded GPT-5.5 capability in Codex over the last 48 hours.
@Fenng: When a simple bug won’t go away with Codex, check the model—if it’s GPT-5.4, start a fresh session and switch to GPT-5.3-Codex; the fix may come instantly. You’re welcome.
Fenng advises swapping from GPT-5.4 to GPT-5.3-Codex when a straightforward bug keeps eluding resolution, hinting that model choice can sway debugging success.
@LexnLin: Codex growth is insane. Already 5M users Gotta GPT 5.5 xhigh /fast max now
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@fiapp_pro: Officially announce, Codex GPT5.5 high is completely dead, probably because OpenAI is training GPT-5.6. Its performance on Codex is very lazy, hallucinates, loses context. Must enable xhigh to restore normal performance.
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