Microsoft Decouples AI Agents From the VS Code Editor in Latest Release

Microsoft has released Visual Studio Code 1.133, introducing a significant architectural change to its AI agent functionality. Rather than executing AI agent sessions within the editor's extension host, the sessions now run in a separate background process called the Agent Host, built on a new open specification known as the Agent Host Protocol (AHP).

This move allows multiple VS Code windows to connect to the same session and share a synchronized view, enabling remote execution through SSH or dev tunnels. Microsoft has provided first-party adapters for popular AI agents like Copilot, Claude, and Codex, translating their native runtimes into the AHP session model. This development allows DevOps teams to mix Anthropic and Copilot models within the same session, with per-turn model selection and separate billing.

An experimental setting, chat.agentHost.allowSignedOutWhenUsable, now enables the Agents window to open without a mandatory GitHub sign-in prompt, attaching authentication to individual agents or models instead of the entire window. Developers can also start the Agent Host manually or expose it through a dev tunnel for remote access.

Additionally, the update includes user-friendly improvements such as sticky scroll for chat prompts and auto-refresh for local HTML files. Microsoft's decision to publish the AHP as an open specification signals a strategic shift, positioning AI agent execution as independent infrastructure rather than a VS Code-specific feature.