Sonnet 4.5 is no longer offered in the dashboard model pickers. Existing configurations can continue using it until migration. API requests that explicitly submit
claude-4.5-sonnet are normalized to claude-4.6-sonnet, so resubmitting the model in an update switches that configuration before the migration date.
You can select Sonnet 4.6 now to test your agents before the automatic migration. If your integration specifies a model, use claude-4.6-sonnet in future API requests.
See all deprecation notices.