What's new in Microsoft 365 Copilot extensibility

As a developer, you can extend, enrich, and customize Microsoft 365 Copilot for the unique way your customers work. This article provides the latest information about what's new in Microsoft 365 Copilot extensibility.

For the latest information, announcements, and news about preview and generally available (GA) features, follow the Microsoft 365 Copilot developer blog.

May 2025

Microsoft 365 Agents Toolkit

Use Microsoft 365 Agents Toolkit (an evolution of Teams Toolkit) to Build declarative agents and Build Copilot connectors.

Microsoft 365 Copilot APIs

The Microsoft 365 Copilot APIs provide a comprehensive set of capabilities that enable you to build AI-powered applications grounded in enterprise data. For more information, see Microsoft 365 Copilot APIs overview.

API plugin manifest version 2.3

A new version of the API plugin manifest schema is available. API plugin manifest schema 2.3 for Microsoft 365 Copilot adds support calling functions in an Office Add-in.

Declarative agent manifest version 1.4

A new version of the declarative agent manifest schema is available. Declarative agent manifest schema version 1.4 adds the following.

• Added the sensitivity_label, disclaimer, and behavior_overrides properties to the Declarative agent manifest object.
• Added the part_type and part_id properties to the Items by SharePoint IDs object.
• Added the Scenario models capability.

April 2025

Copilot Studio message usage rates

Updated the usage rates for Copilot Studio messages. For more information, see Copilot Studio message usage rates.

Email as knowledge

Email is now available as a knowledge source for agents build with Microsoft 365 Agents Toolkit (an evolution of Teams Toolkit). For more information, see Email knowledge.

Copilot Studio agent builder templates

Use templates in Copilot Studio agent builder to streamline your agent development process. For more information, see Agent builder templates overview.

Document interaction for declarative agents in Word

Declarative agents in the Copilot experience in Word can interact with the open document. Users can provide the current selection to the agent and can insert images provided by the agent into the document.

March 2025

Declarative agent manifest version 1.3

A new version of the declarative agent manifest schema is available. Declarative agent manifest schema version 1.3 adds support for the following capabilities:

• Dataverse knowledge
• Teams messages as knowledge
• People knowledge

February 2025

Copilot Studio agent builder available in Copilot Chat

Microsoft 365 Copilot Chat users can now access Copilot Studio agent builder to build agents in the Microsoft 365 Copilot app and the Copilot app in Teams.

Add websites as knowledge in agent builder

You can add specific public websites as agent knowledge sources to make your agent context-aware. For details, see Web content.

Custom engine agents available in Copilot app (preview)

Custom engine agents are now available to users who have Microsoft 365 Copilot licenses or users in tenants with metering enabled in the Microsoft 365 Copilot app (for preview), in addition to Teams.

January 2025

Links are no longer redacted in Copilot responses

Links to organizational and web resources are no longer redacted from Copilot responses. Links that don't explicitly match grounding data or resources defined in the agent manifest continue to be redacted.

Build agents for Microsoft 365 Copilot Chat

You can now build agents for Microsoft 365 users who don't have a Microsoft 365 Copilot license, grounded on the web and with limited capabilities. For more information, see Agent capabilities for Microsoft 365 users.

December 2024

Add code interpreter to your declarative agent

Add the code interpreter capability to your declarative agent by using the Copilot Studio agent builder or Agents Toolkit. To learn more, see Add capabilities to your declarative agent.

November 2024

Add image generator to your declarative agent

Add the image generator capability to your declarative agent by using the Copilot Studio agent builder or Agents Toolkit.. To learn more, see Add capabilities to your declarative agent.

Declarative agent manifest version 1.2

A new version of the declarative agent manifest schema has been released. Version 1.2 adds support for scoped web search and the new code interpreter and image generator capabilities. To learn more, see Declarative agent schema 1.2 for Microsoft 365 Copilot.

API plugin manifest version 2.2

A new version of the API plugin manifest schema has been released. Version 2.2 adds support for data handling attestation. To learn more, see API plugin manifest schema 2.2 for Microsoft 365 Copilot.

October 2024

Use the Copilot Studio agent builder to build declarative agents

Use the Copilot Studio agent builder to create and customize agents for your specific scenarios. With the agent builder, you can use natural language to describe your agent, or you can build it manually via a rich authoring experience. To learn more, see Overview of Copilot Studio agent builder.

September 2024

Build your own agent

You can build your own agents to focus on your specific use cases. Provide custom instructions to tailor responses, ground agents in your organization's data, and add more skills with actions.

You can build agents in two ways:

• Build declarative agents by using the Microsoft 365 Copilot orchestrator and foundation models. You can use Visual Studio Code or the Copilot Studio agent builder.
• Build custom engine agents with your custom orchestrator and foundation models by using Azure AI Foundry and Visual Studio Code.