Switch to V3 at Chat Start and Model Fallback Notices

This release shows a startup prompt inviting you to switch to V3 as part of a gradual rollout. It also adds V3 model fallback notices, keeps more of your V2 agent access when you upgrade agents to V3, and fixes screen reader, tmux, and knowledge search issues.

The startup prompt is rolling out gradually before V3 becomes the default with CLI 3.0 at the end of October, so you may not see it right away. When it appears, choose Switch to V3 and upgrade my configs to save V3 as your default harness, enable automatic agent upgrades, and start migrating your custom agent configurations. You can also try V3 anytime with kiro-cli --v3. Read the Kiro CLI V3 rollout announcement for details.

In V3 sessions, when a model refuses a request or is unavailable and the turn moves to another model, the transcript now shows a notice. You can tell that a different model continued the turn instead of wondering why a reply changed. Learn about model fallback notices.