Microsoft and Anthropic have announced a significant expansion of their partnership, bringing Anthropic’s frontier AI models—Claude Sonnet 4.5, Haiku 4.5, and Opus 4.1—into public preview on Microsoft Foundry. This move allows Azure customers to build sophisticated production applications and enterprise agents leveraging these advanced models directly within Microsoft’s ecosystem.​

Claude Models Now Available in Microsoft Foundry

As part of the enhanced collaboration, Microsoft Foundry users can deploy Claude models seamlessly through serverless deployment, which supports scalable development while Anthropic manages the underlying infrastructure. Developers benefit from:

• Immediate deployment using Foundry’s APIs, tools, and workflows

• Compatibility with existing Azure agreements, including the Microsoft Azure Consumption Commitment (MACC), simplifying procurement and billing

• Access to SDKs in popular programming languages like Python, TypeScript, and C#, secured via Microsoft Entra authentication​

Choosing the Right Claude Model for Enterprise Needs

Microsoft customers can select from three Claude models to meet varied enterprise and development demands:

• Claude Sonnet 4.5 is recognized as the world’s leading coding model, excelling in complex reasoning, multi-step workflows, and autonomous coding tasks. It’s ideal for building powerful AI agents.

• Claude Haiku 4.5 focuses on speed and cost-efficiency, delivering near-frontier performance at about one-third the expense of Sonnet. This makes it perfect for high-volume tasks like customer support automation or content moderation.

• Claude Opus 4.1 offers specialized reasoning for complex, detail-oriented problems requiring sustained attention.​

Enhanced AI Integration in Microsoft 365 Copilot and Excel

Beyond Foundry, the partnership expands Claude’s reach into Microsoft 365 Copilot, where Claude powers the Researcher agent for advanced, multistep research and supports custom agent development in Copilot Studio. A notable new feature is Claude’s integration into Microsoft Excel’s Agent Mode—now available in preview—where Claude helps users generate formulas, analyze data, identify errors, and iterate on solutions, streamlining office workflows.​

Additional Features and Resources

All Claude models in Foundry support a rich set of developer capabilities, including code execution, web search, data fetching, citation generation, vision processing, tool use, and prompt caching. Microsoft and Anthropic provide extensive documentation to help developers explore and fully leverage these features.​

Getting Started

Claude Sonnet 4.5, Haiku 4.5, and Opus 4.1 are now publicly available in Microsoft Foundry’s Global Standard deployment, with US DataZone access rolling out soon. Enterprises can deploy these models through the Microsoft Foundry catalog, and detailed guides are available to assist developers in integrating Claude into their applications.