enforceAvailableModels locks model allowlists org-wide; defaults and user settings can no longer bypass admin-approved models.
enforceAvailableModels setting completes the governance loop: prior releases introduced model allowlists, but policy enforcement was incomplete until now.enforceAvailableModels managed setting — when enabled, the availableModels allowlist also constrains the Default model (a Default that would resolve to a disallowed model now falls back to the first allowed model), and user or project settings can no longer widen a managed availableModels list