Claude's voice mode expands to Opus and Sonnet models

Anthropic's original voice mode launch in 2025 centered on speed: quick answers with minimal delay through the lightweight Haiku model. However, the company discovered that real users were applying voice interaction to harder problems—working through business challenges that demanded sustained reasoning and follow-up actions. Haiku, designed to keep conversations quick, was not equipped for this deeper work. By expanding to Opus and Sonnet, Anthropic is responding to demonstrated user behavior rather than anticipated use. The models can now not only generate complex analysis but also take actions: drafting a one-page pitch from a conversation, or reshuffling calendar appointments based on a user's stated need. The mid-conversation model switching feature amplifies this: users can start lightweight and escalate only when necessary, avoiding the cost and latency of running the most powerful model for every query. The expansion of language support—especially the addition of Japanese alongside eight others—signals an intentional move into non-English markets where voice interaction removes typing friction.