You'll noticeTier: how much it should matter to you
3Useful: my rating, 1 to 5
4Signal: worth watching, 1 to 5
ModelsArea: what it touches
ImprovementsKind: in v2.1.283,
What probably matters to youSection of the release
What
Claude Code keeps a list of which model to fall back to when the session's model refuses a request in a given category. For sessions on claude-opus-5-5, that list now includes the frontier_llm category, which falls back to claude-opus-5. Before, only the bio and cyber categories had fallbacks. The default list gains the same entry.
Why
If you use Opus 5.5 and hit this kind of refusal, Claude Code may now retry on Opus 5 instead of stopping at the refusal.
