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Microsoft's Researcher agent can now be powered by Claude Opus 4.1.
Anthropic's models are also now available in Copilot Studio.
Microsoft has been distancing itself from its dependence on OpenAI.
Microsoft is continuing to invest in its new partnership with Anthropic, while distancing itself further from OpenAI.
On Wednesday, the tech giant announced that two of Anthropic's frontier models, Claude Sonnet 4 and Opus 4.1, were now available through its Copilot AI assistant.
Also: Microsoft's new Windows AI Labs lets you try experimental features first - how to opt-in
"Copilot will continue to be powered by OpenAI's latest models, and now our customers will have the flexibility to use Anthropic models too," Charles Lamanna, president of Copilot's business and industry division at Microsoft, wrote in a company blog post.
Claude Opus 4.1 in Researcher
Microsoft 365 Copilot subscribers will now have the option to choose between OpenAI's reasoning models and Claude Opus 4.1 when using Microsoft's Researcher, an AI agent within Copilot designed to handle complex, multistep tasks.
Also: Microsoft Copilot is taking over Teams. Here's how AI will shape your daily workflow
Users will see a "Try Claude" button in the top-right corner of Copilot when using Researcher. Selecting it will activate Opus 4.1 instead of OpenAI's models, which the system uses by default.
Claude in Copilot Studio
Claude Sonnet 4 and Opus 4.1 are also now available through Copilot Studio, a platform Microsoft launched last year through which customers can design custom agents. Studio also has mix-and-match capabilities enabling the design of agents that incorporate elements of models from OpenAI, Anthropic, and others hosted on Azure.
OpenAI's GPT-4o is still included as the default model for custom agents made in Copilot Studio. To select a different OpenAI model or one of the two Claude models that are now available, users can click on the ellipses next to "Agent's model" in the Details section. They'll then be directed to a new window where they can click a drop-down menu to choose from all of the available models.
Also: OpenAI tested GPT-5, Claude, and Gemini on real-world tasks - the results were surprising
Both Claude models are listed as "external," since they're not hosted by Microsoft's servers and are therefore subject to Anthropic's terms of service.
A shifting dynamic
The addition of Anthropic's frontier models to Copilot marks Microsoft's latest effort to diversify its AI offerings for customers.
Until recently, the company was almost exclusively dependent upon OpenAI to fuel its AI products. But as OpenAI shifts its business structure -- it's also reportedly now partnering with Google, Microsoft's biggest competitor, to gain access to its cloud computing resources -- the two companies have drifted apart.
Also: How people actually use ChatGPT vs Claude - and what the differences tell us
Microsoft kicked off a partnership with Anthropic earlier this month, embedding the startup's AI systems across its suite of Microsoft 365 workplace productivity apps. That news followed closely on the heels of Anthropic's latest funding round, which left it with a valuation of $183 billion, a massive figure fueled in large part by the popularity of the company's products among enterprise clients.
Microsoft also announced the launch last month of its first in-house models, MAI-Voice-1 and MAI-1-preview -- another move that signaled an ongoing drift away from OpenAI.