Leak: Anthropic Opus 5.5 may land Monday or Tuesday, with always-on adaptive thinking
mark_k · x · 2026-09-21
Unconfirmed leak from X user lyraxana claims Anthropic's Opus 5.5 is arriving next week — possibly Monday, dated Tuesday.
Details:
- Anthropic marked the release "imminent" and partners got only 24h access.
- Thinking is ALWAYS adaptive, with no "off" mode.
- Forced tool use is retired.
- Pricing details were included in the leak.
Not yet confirmed by Anthropic.
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