Anthropic opens Claude Duet, a proactive agent that keeps working while you step away

On October 21, 2026, Anthropic opened a research preview of Claude Duet, an app in which Claude acts as a proactive agent: a morning brief, monitoring of your connected apps and background task execution, with systematic approval before any sensitive action. The promise is bold, but it is the safety stack — leak-blocking classifier, credentials never exposed, sensitive actions gated — that will decide whether the bet holds.