Claude API thinking.display adds an updates mode in beta

BetaSep 1, 2026VerifiedAdded Sep 22, 2026

The new updates value, behind the thinking-display-updates-2026-08-18 header, returns reasoning empty like omitted but surfaces the short progress updates Fable and Mythos models write between tool calls as text.

LLMs

Read Anthropic's release notes

https://platform.claude.com/docs/en/release-notes/overview#september-1-2026

Summaries of vendors' own notes. Product names and logos belong to their owners; logos via logo.dev.

More Claude Platform releases

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Claude PlatformSep 1, 2026

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UpdateLLMsSource

Claude PlatformSep 1, 2026

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Claude PlatformSep 1, 2026

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BetaLLMsDeveloper toolsSource

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BetaPricingSource

Claude PlatformSep 1, 2026

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UpdateLLMsSource

Also shipped on Sep 1, 2026

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BetaSource

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