Claude Duet is Anthropic's proactive AI agent, launched October 21, 2026 as a research preview for US Pro and Max subscribers on a waitlist. It runs on its own cloud computer, checks your connected apps every few hours, sends a morning brief and drafts replies before you ask. It asks for your approval before it sends, pays or deletes anything, and its background work counts against your normal Claude usage limits.
The cautionary tale: Meta Muse's exposed chat links
The episode opens with what went wrong for a rival. A security researcher found more than 6,800 Meta Muse chat share links in passive DNS records, the background network logs that record which addresses get looked up. The sample included business material such as a loan application and an internal revenue review. Meta said it paused the sharing feature while it investigates, and the pages no longer opened on recheck.
That is the backdrop for any always-on assistant: the more of your inbox and business it can see, the more it matters how its sharing and access are built.
What Claude Duet actually is
A normal chatbot waits for a prompt. Duet operates its own virtual computer in the cloud and checks in every few hours. It connects to your work apps, and Anthropic says it never directly sees your passwords. Per MacRumors, it sends a morning brief across email and calendar and only pings you when something needs you. It runs on Opus 5.5.
You talk to it through one ongoing thread. Dump tasks and half-formed thoughts in, and Duet sorts them into channels for different projects, a bit like a Slack workspace. One source nicknamed this the "God Thread."
The safety design: approval cards
The key mechanism is that Duet prepares the work but cannot spend your money or send a message on its own. It shows a card with two buttons: approve or not now. For payments, it integrates with services like Link and Stripe to generate single-use virtual cards, so your real payment details are not exposed to the merchant or saved by the AI. As @zahareus put it, it "works in its own VM while you're away, and asks before sending, paying or deleting."
Early reviews are mixed. Dan Shipper's two-week early-access review, as reported by Super Power Daily, finds Duet's email drafts weaker than OpenAI's, and says scheduled runs cannot use custom connectors. Flavio Copes notes that disconnecting an app does not erase what Duet already learned.
The catch: your Claude limits
Background checks, morning briefs and multi-step jobs all run on Opus 5.5, so they draw from the same plan allowance as normal Claude use, even while you are away. The r/Anthropic "Claude limits" thread is full of this complaint. Amine AI warns Pro users to watch out if Duet goes on tangents or takes on heavy tasks. By contrast, OpenAI's Dots conversations do not count toward ChatGPT limits, per the research sweep behind this episode.
Two things to do today
Join the Duet waitlist at claude.com if you are a US Pro or Max subscriber, using the email tied to your Claude account.
Look at Zapier's MCP integration. MCP, the Model Context Protocol, is a standard that lets AI models connect to your data. Connect your most-used business app (an email marketing tool like Drip, or Shopify) to your Claude account now so your connected apps can carry over once you get access.
Also decide in advance what the assistant may never do without your approval.
Why auditing is the skill that matters
As tools like Duet automate daily execution, speed stops being the valuable skill. Your success will depend on how effectively you can audit and verify the automated decisions made in your name. Anthropic itself admits Duet can misjudge how urgent a message is or miss mail that lands between checks, per iPhoneSoft.
FAQ
What is Claude Duet?
Claude Duet is Anthropic's always-on AI agent. It runs in the cloud, checks your connected apps every few hours, sends a morning brief and drafts replies for your approval.
Who can use Claude Duet right now?
It is a research preview behind a waitlist for US Pro and Max subscribers, available in a mobile app and through claude.ai.
Can Claude Duet spend money or send email on its own?
No. It shows an approval card before sending, paying or deleting. Payments use single-use virtual cards.
Does Claude Duet use up my Claude limits?
Yes. Its background checks draw from the same usage limits as your normal Claude use, including while you are away.
Companion episode:
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