Mid-conversation tool changes beta for Fable, Mythos, Opus models

July 24, 2026Claude PlatformView original ↗

1 feature

Mid-conversation tool changes are now in beta on Claude Fable 5, Claude Mythos 5, Claude Opus 4.8, and Claude Opus 5. Add or remove tools between turns while preserving the prompt cache. Include the mid-conversation-tool-changes-2026-07-01 beta header in requests.

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Fetched July 28, 2026