Opus 5.5 ships with a new responsive mode that answers in a sentence before thinking

fsharpman · reddit · 2026-09-23

A Reddit user highlights details from the Opus 5.5 release notes, including a new responsive mode: Claude now replies with a sentence before thinking or invoking tools on every prompt. The poster also notes noticeably lower token usage, echoing the official claim that Opus 5.5 matches Fable 5.1 on most work while costing 40% less to run than Opus 5.

Related event: Anthropic Launches Claude Opus 5.5: Smarter, Faster and 40% Cheaper(56 posts)→

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