More choice, more flexibility: xAI Grok 4.1 Fast now available in Microsoft Copilot Studio

The words try xAI models in Microsoft Copilot Studio appearing on a blue, magenta, and purple background.
xAI models are now available in Copilot Studio, expanding your multi‑model lineup with a new option for fast reasoning and flexible agent design.

Starting today, xAI joins Microsoft Copilot Studio’s growing model provider lineup. Once enabled by organization administrators, United States-based makers can build with Grok 4.1 Fast and tap into deeper model choice, with readiness evaluations underway for other regions.

Grok 4.1 Fast is a fast‑reasoning, text‑generation model (generation of images and other media types are not supported) that is designed for large context, deep tool use, and can be used to handle complex workflows. This addition reflects our ongoing commitment to give you more flexibility when designing and optimizing agents—so you can choose the right model for every business scenario.

Expanding our model line-up

Copilot Studio aims to give makers the ability to evaluate and use the model best suited to transform their business. With the addition of xAI Grok 4.1 Fast, we’re building on that commitment.

Alongside OpenAI and Anthropic models, xAI adds even more depth to your multi‑model lineup—while still keeping responsible AI principles at the center. Before rollout, every model in your Copilot Studio lineup goes through security, safety, and quality evaluations.

When using Grok 4.1 Fast in Copilot Studio, customer data is not retained or used to train xAI’s models. xAI’s models are hosted outside Microsoft-managed environments, and when you use Grok 4.1 Fast in Copilot Studio, your relationship with xAI will be independent of Microsoft and governed by xAI’s Enterprise Terms of Service and Data Protection Addendum.

Unlocking the power of model choice

Starting today, Grok 4.1 Fast is available in preview in early access environments, and is off by default. Your organization’s admin must explicitly opt in to use the model before US-based makers can build with it.

If an admin doesn’t opt in, nothing changes and makers keep their current model options. Existing agents continue running exactly as they do today.

Learn more about admin opt-in controls:

Ami Shastra's headshot

Ami Shastri

Principal Product Manager, Copilot Studio
Ami Shastri leads model strategy and agility for Microsoft Copilot Studio, the platform for discovering, customizing, and building enterprise-ready AI agents and agentic workflows. Copilot Studio enhances employee productivity by handling long-form tasks as an employee would or operating autonomously. The platform offers a comprehensive studio for building, orchestrating, and overseeing AI agents, and is utilized by thousands of companies.
See more articles from this author