Fixed plan-mode model selection not checking the allowlist when upgrading from Haiku or Opus plan model — the upgrade model is now validated and falls back gracefully with a warning rather than attempting to use an unauthorized model. (search for "Plan mode: the haiku plan upgrade model is not in the availableModels allowlist")
Fixed a regression where model name matching used an incomplete word-boundary check that could incorrectly match substring model names in the allowlist. The new matcher (ekK) requires non-alphanumeric boundaries on both sides of the match. (search for "ekK" — the new boundary-aware substring matcher)
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Anthropic's release notes agreeAdded enforceAvailableModels managed setting — when enabled, the availableModels allowlist also constrains the Default model (a Default that…
