GPT 5.5 seems to be degraded
OpenAI Developer Community
June 10, 2026
BlastoLabs:
> Try using GPT 5.5 via the api with zero context and you will see that this issue is caused by your usage and not GPT 5.5 suddenly not working as well.
that’s exactly what I mentioned early on that I started from clear context to measure both and 5.5 did not perform up to par with 4.8
the API and what you use from codex subscription are exactly the same.
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