Custom Engine Agents now generally available—build and integrate your own AI into the flow of work

Microsoft 365 Copilot is redefining how people interact with AI—embedding it directly into the flow of work as the intuitive, natural interface for agents: the ‘UI for AI’

As Copilot becomes the interface for AI in the workplace, we’re seeing growing demand from customers who want to extend its capabilities with their own solutions. Many of our customers are looking to create custom agents—or have already built agents that operate outside the Microsoft 365 ecosystem—using fine-tuned models, custom logic, orchestrators, tools, knowledge sources, or complex integrations with other systems. Today, we’re enabling them to bring these agents into Microsoft 365 Copilot. We’re excited to announce the General Availability of custom engine agents in Microsoft 365 Copilot.

No matter where or how developers build their agents—whether with Copilot Studio, Azure AI Foundry, Visual Studio, or other AI platforms—they can now bring them into Microsoft 365 Copilot with a seamless, native experience. This integration gives developers full control over agent behavior, data access, and user interaction—ensuring consistency, security, and adaptability across the Microsoft 365 ecosystem.

Custom engine agents bring LexisNexis Protégé™ to life in Microsoft 365 Copilot

Build agents with full flexibility

Whether you’re starting fresh or extending existing solutions, with full control over logic, data access, and user interaction, developers can:

• Define custom workflows and logic using code to match specific business processes.
• Bring their own orchestration and models, including proprietary or fine-tuned LLMs—from Azure AI Foundry, Hugging Face, or other sources.
• Integrate with external APIs and systems to automate complex tasks, enable real-time data retrieval, and extend functionality beyond native Copilot capabilities.
• Implement asynchronous patterns, such as long-running tasks and proactive alerts, to keep users productive while agents work in the background.
• Deploy across Microsoft 365 Copilot, Teams, and other channels with enterprise-grade security and compliance.
• Build with enhanced security and compliance controls, ensuring agents align with organizational policies and regulatory requirements.

Accelerate custom agent development with the Microsoft 365 Agents Toolkit and SDK

Developers can move faster and build custom engine agents for Microsoft 365 Copilot with the Microsoft 365 Agents Toolkit—available in both Visual Studio and Visual Studio Code. It streamlines the custom agent-building process with built-in scaffolding, debugging tools, testing, and seamless integration with the Microsoft 365 Agents SDK.

Once published, agents are instantly discoverable in the Agent Store, ready to meet users where they work—across Microsoft 365 Copilot, Teams, and more.

Watch how you can easily build your custom engine agent with Azure AI Foundry models and publish it to Microsoft 365 Copilot with the Toolkit and SDK.

Introducing support for asynchronous scenario patterns

We’re also introducing new native patterns for agents in Microsoft 365 Copilot, enabling developers to build custom agents that operate asynchronously—unlocking richer, more flexible user experiences. Unlike traditional synchronous interactions, these patterns allow agents to continue working in the background or proactively engage users when needed.

With asynchronous scenario patterns, custom agents can now:

• Follow-up messages: Custom agents can perform background processing—such as data analysis or report generation—while users continue working in other parts of the Copilot interface. For instance, a user might ask to order a replacement laptop, and the agent can handle the request in the background without interrupting their workflow.
• Long-running tasks: Agents can manage extended operations asynchronously, allowing users to initiate a task and receive a notification once it’s complete. For example, an agent could watermark all the documents in a SharePoint site while the user moves on to other work.
• Proactive alerts: Agents can send timely notifications without requiring a user prompt—like reminding someone to enter interview feedback—helping users stay on top of important actions.

Seamless Integration in Microsoft Teams and Microsoft 365 Copilot

The experience for custom engine agents is designed to feel like a native part of Microsoft 365 Copilot. Once approved and published in the Agent Store, they’re instantly available to users—no separate installation required. Whether in Microsoft Teams or the Microsoft 365 Copilot web or desktop app, users can discover, launch, and interact with agents directly from Copilot Chat and sidebar.

Agents greet users with a friendly welcome message and offer suggested prompts to help them get started—making the experience intuitive and Copilot-native from the very first interaction. Users can browse agent descriptions, install their favorites, and pin them for quick access within the flow of work.

We are excited how our partners are building their custom agents for Microsoft 365 Copilot now available in the Agent Store including, SAP Joule, LexisNexis Protégé, Meltwater and Asana. These agents bring the customization needed from our partner’s agentic use cases to the flow of work in M365 Copilot. We are introducing additional agents from more partners in the upcoming weeks.

Enterprise-grade control—just like other Copilot agents

Custom engine agents follow the same management and governance model as other agents in Microsoft 365 Copilot, giving IT admins the confidence and control they need to scale securely. Through the Microsoft 365 admin center, admins can:

• Approve or block agents in the Agent Store to manage availability across the organization
• Control access using security groups and role-based permissions
• Define data access policies to ensure agents only interact with approved sources
• Monitor usage and performance with built-in reporting and analytics
• Enforce compliance with organizational policies and regulatory requirements
• These capabilities ensure that custom engine agents can be deployed and managed with the same rigor, flexibility, and security as any other Copilot-native experience.

Turn your code into agents for Microsoft 365 Copilot today!

With custom engine agents now generally available, developers and organizations can shape how AI shows up in the flow of work. From custom logic and models to secure, scalable deployment, we empower teams to build agents that reflect their unique needs and work—directly within Microsoft 365 Copilot.

To get started, download the Microsoft 365 Agents Toolkit for Visual Studio and Visual Studio code and bring your first agent to Microsoft 365 Copilot in minutes. You can follow along these resources:

• Learn more about custom engine agents here:
  • Developer documentation
• Follow a step by step tutorial:
  • Build your own agent with the M365 Agents SDK and Semantic Kernel
• Watch how:
  • Bring an Azure AI Foundry Agent into Microsoft 365 Copilot and beyond
  • Create agents for Microsoft 365 Copilot with the M365 Agents SDK

We look forward to seeing what great agents you bring to Microsoft 365 Copilot.