GPT-5-thinking No longer Thinks at all. | OpenAI | Page 1

Reported by @scenic jetty

Bug Report: GPT-5-thinking No longer Thinks at all.

`Steps to Reproduce`

Ask a question with gpt-5-thinking, and it does not think at all. There is no COT summary or thinking time, rather the message is given instantly, as if the model reverts to GPT-5-instant. This occurs even when the thinking time is set to "extended". Regenerting the response (via the "try again") button makes it think again, however this is quite an annoying step.

The quality of the response is signicantly lower as a result of thinking being absent. GPT-5-thinking-mini seems to be fine.

`Expected Result`

The model should actually go through it's thinking process if GPT-5-thinking is explicitly mentioned in the model selector.

`Actual Result`

The model does not think at all. Only when you regenerate the response, either through "try again" or "try again with thinking" (even though it's already on gpt-5-thinking") does the model start to think again.

Without thinking, the response quality is severely degraded, and it response more like gpt-5-instant (praises the question uncessarily, and provides incorrect outputs).

`Environment`

Chatgpt Web version (Edge, and Chrome)

Additional Information

Please provide relevant details to help resolve the issue, such as:

ChatGPT Shared Link (if applicable).
Screenshots or videos demonstrating the problem.

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#GPT-5-thinking No longer Thinks at all.