Relations between Microsoft 365 Agents Toolkit and TeamsFx

[alspires]

Hello,

I am creating a new Teams Bot, but I'm a bit confused about what I should be using to achieve this. Some Microsoft documentations tells us to use Microsoft 365 Agents Toolkit to scaffold, sideload and publish projects and at the same time, tells us that TeamsFx will be deprecated soon.

My concern is that I have plenty of files that have been scaffolded using the latest CLI with: teams config add atk.basic which have "TeamsFx" on them.

What is the connection between using the latest CLI and TeamsFx? If those are wrong and really going to be deprecated next year, what should I be using to deploy my Teams app, to create CI/CD scripts, etc.?

Any clarification is appreciated.

Thanks!

[VikrantSingh01]

The Short Answer

Microsoft 365 Agents Toolkit is the evolution and rebrand of Teams Toolkit (which was originally called TeamsFx). They are the same product line, not separate tools. The "TeamsFx" references you see in scaffolded files are expected legacy artifacts — they do not mean you are using a deprecated tool.

The Full Picture

Naming Timeline

The product has gone through several name changes:

Era	Tool Name	CLI Command
Original (2020-2022)	TeamsFx	teamsfx
Intermediate (2023-2025)	Teams Toolkit	teamsapp
Current (2025+)	Microsoft 365 Agents Toolkit	atk

The GitHub repository itself was renamed from OfficeDev/TeamsFx to OfficeDev/microsoft-365-agents-toolkit. The VS Code extension was renamed from "Teams Toolkit" to "Microsoft 365 Agents Toolkit." The rename reflects Microsoft's expanded focus on building intelligent agents and apps across the entire Microsoft 365 ecosystem (Teams, Outlook, Copilot), not just Teams.

Why You Still See "TeamsFx" in Scaffolded Files

This is expected behavior, not a bug or a sign that you are using something deprecated. There are a few reasons these references persist:

1. Configuration keys and environment variables: Internal identifiers like TeamsFx in appsettings.json, TEAMSFX_* environment variables, and <ProjectCapability Include="TeamsFx"/> entries were kept for backwards compatibility so that existing projects continue to work after upgrading the toolkit.

2. The @microsoft/teamsfx SDK package: Some scaffolded templates may still reference this npm package. This is the client-side SDK that provided helpers for authentication, data access, and other common patterns in Teams apps.

What You Should Know About the TeamsFx SDK

It is important to distinguish between the toolkit (the CLI/extension you use to scaffold, provision, deploy, and publish) and the SDK (the @microsoft/teamsfx npm package your app code depends on at runtime):

• The toolkit (now called Microsoft 365 Agents Toolkit) is actively developed and is what you should use. The atk CLI provides atk provision, atk deploy, atk publish, and other commands for your CI/CD pipelines.
• The @microsoft/teamsfx SDK is in deprecation mode. It will receive community-only support on GitHub until September 2026. No new features will be added.

For new projects, Microsoft recommends using:

• Teams AI Library v2 — for Teams-only apps and bots (tabs, message extensions, AI-powered chatbots within Teams). This is the direct successor.
• Microsoft 365 Agents SDK — for agents that need to work across multiple channels beyond Teams (Copilot, Outlook, third-party messaging).

What to Use Going Forward

Task	What to Use
Scaffolding new projects	M365 Agents Toolkit (atk CLI or VS Code extension)
Provisioning cloud resources	atk provision
Deploying to Azure	atk deploy
CI/CD pipelines	The atk CLI — supports all the same operations as the VS Code extension
Publishing to Teams	atk publish
Runtime SDK for new apps	Teams AI Library v2 or M365 Agents SDK

Will Existing Projects Break?

No. Existing projects that reference @microsoft/teamsfx will continue to work. The SDK will be maintained (community support) through September 2026. You do not need to urgently migrate, but for new projects you should start with the newer SDKs.

If you want to upgrade an existing project to work with the latest version of the toolkit, you can run:

atk upgrade

References

• M365 Agents Toolkit Overview
• Agents Toolkit CLI Documentation
• Tools and SDKs Overview
• TeamsFx SDK Deprecation Notice