Microsoft has started releasing Copilot Cowork to a limited group of early users through its Frontier program. Reuters reported that the tool was still in testing and would be available to early-access users later in the month, while Microsoft’s own blog says it is being tested with a limited set of customers in Research Preview and will be more broadly available in Frontier in late March 2026.
Microsoft is positioning Copilot Cowork as a shift from simple chat to task execution inside Microsoft 365. Microsoft says the tool is designed to “take action, not just chat,” by turning a user’s request into a plan and then carrying out work across email, meetings, messages, files, and data with checkpoints for approval.
New feature “Critique”
A key part of the update is Critique, which Microsoft says is built into Researcher, one of the Copilot experiences. In Microsoft’s description, one model drafts the work and a second model reviews and refines it, separating generation from evaluation. The feature combines models from Anthropic and OpenAI.
Microsoft says Critique improves Researcher’s quality on its internal measurement, the DRACO benchmark, by 13.8%. That claim comes from Microsoft’s own blog post, so it should be read as a company-reported result rather than an independently verified industry benchmark.
The logic behind Critique is straightforward: rather than relying on one model to produce and judge its own output, Microsoft is using a second model as a reviewer. In practical ways, this is meant to reduce errors and improve the quality of longer research tasks.
Copilot Cowork for early users
Copilot Cowork is built to handle multi-step work inside Microsoft 365. The company describes it as using Work IQ signals from Outlook, Teams, Excel, and other Microsoft 365 services so it can understand context, draft a plan, and keep working in the background while the user reviews progress.
The rollout is limited for now, Microsoft says the feature is being tested with a small set of customers in Research Preview and will be more broadly available through Frontier in late March 2026. Microsoft had not disclosed pricing, but said some usage would be included in the company’s $30-per-user-per-month M365 Copilot enterprise plan, with additional usage available for purchase.
Copilot Cowork runs within Microsoft 365 security and governance boundaries, with identity, permissions, compliance, and auditability applied by default. That matters because enterprise buyers usually look for control and traceability before they let AI systems act on files, meetings, and messaging data.
Model Council
Alongside Critique, Microsoft has added a “model Council” view in Researcher. The company says this model lets users compare responses from different models side by side, so they can see where the models agree, where they differ, and what each one adds.
Microsoft is now making Anthropic’s Claude Sonnet models available to M365 Copilot users as well, whereas the service had previously relied only on OpenAI’s GPT models.
