Anthropic previews Claude Duet, an Opus 5.5 proactive agent

• Duet surfaces work and keeps running after the user steps away, as Anthropic describes in its research-preview announcement.
• Opus 5.5 powers the app, with existing Claude memory, skills and app connections carried over.
• Background activity consumes the existing Claude plan quota, according to WesRoth's launch summary.
• Access starts with a US-only waitlist for Pro and Max subscribers, according to Anthropic's availability notice.

Only the user can mark a task complete, a neat bit of friction. Disconnecting an app stops new access without erasing information Duet already remembers. In Every's early testing, it could see other Claude sessions but couldn't direct them.

Anthropic says Duet can notice work before being asked. It runs on a cloud VM with its own browser, independent of the user's devices, and checks connected accounts every few hours to conserve plan quota.

One internal tester described using it for three jobs:

• Drafting questions for a fireside chat.
• Watching Slack over a weekend.
• Ordering a new Neal Stephenson book from a local bookstore after an explicit request.

Work appears in three surfaces:

• Chat: An ongoing main thread, plus separate topic channels that share the same memory.
• Tasks: Current jobs and items needing the user's input.
• Make: Finished work that can be reviewed and edited, including financial models, slide decks and dashboards.

Duet can also search past Duet conversations and Claude chats outside projects. That access follows Claude's existing “Search and reference chats” setting, according to the setup documentation.

Anthropic advertises more than 6,000 connectors and plugins through the Claude Marketplace. Purchases and revenue operations use separate Stripe integrations:

• Link: Duet confirms the item, Link asks the user to approve the spend, and checkout uses a virtual card rather than exposing the real card number.
• Stripe MCP: Duet can send invoices and payment links, issue refunds, and analyze revenue.

Shop Pay checkout is also supported. Anthropic marks sign-in using saved 1Password credentials as coming soon.

Duet presents proposed actions and waits for approval before sending messages, making payments, signing documents or deleting data, according to Anthropic's launch post. Securities trading and moving money between accounts remain prohibited even with approval.

Anthropic describes five security layers:

• Credential isolation: Duet never directly sees passwords or sign-in tokens, following the credential-handling design used in Claude Managed Agents.
• Action checks: The auto mode classifier also used in Claude and Claude Code checks actions against unwanted steps.
• Prompt-injection defenses: Protections draw on Anthropic's browser-use research and broader model safeguards.
• Disclosure filtering: A new classifier and safety system prompt check each message. They are designed to reject sharing credit card numbers and government IDs; health and personal-finance information require explicit instructions to share.
• Security testing: Internal red teams and an external firm performed penetration testing, and Duet is covered by Anthropic's public bug bounty program.

Dan Shipper, cofounder and CEO of Every, called Duet a “pro tool” after two weeks of testing. His review also identified three gaps:

• Voice input is transcription only, without spoken conversation.
• Email drafts were worse than Dot's in his testing.
• Scheduled runs couldn't reach his custom connectors.

The preview has further documented limits:

• Fixed model: Users cannot choose a model; Duet runs Opus 5.5 and determines task effort itself.
• Hidden browser: Users cannot watch its browser or take over a session.
• Connector exceptions: Microsoft 365 is unavailable, and some connectors, including Slack, have limits.
• Polling gaps: Urgent items can arrive between account checks.

The preview has standalone iOS and Android apps and access through claude.ai. Invitations go out in waves through the product waitlist; Team and Enterprise plans aren't included yet.

The team says the narrow rollout is intended to tune judgment and safety with early users before expanding.

During the preview, Duet costs nothing extra on Pro and Max, but uses both the five-hour session and weekly allowances at the same rate as Claude chats, according to the usage documentation. Morning briefs and background check-ins count, and larger jobs require more model turns.

Newly admitted users receive one full reset of both allowances. That admission reset is available until November 30, 2026.