VS Code agent host runs Copilot, Claude, and Codex in a dedicated process - Help Net Security

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VS Code agent host runs Copilot, Claude, and Codex in a dedicated process

Developers who lean on AI coding agents often keep several editor windows open at once, each tied to its own session. The 1.129 release of Visual Studio Code reworks that setup with a dedicated agent host.

A dedicated process for agent sessions

The agent host is a separate process that runs agent harnesses such as Copilot, Claude, and Codex, built on the Agent Host Protocol. Because a session lives in its own process, one session can connect to and render across several VS Code windows at the same time.

The Copilot agent inside the host draws on the Copilot SDK, so its behavior lines up with the Copilot CLI, the standalone GitHub Copilot app, and other Copilot products. Opting in means enabling thechat.agentHost.enabled setting, which an organization administrator controls, then choosing a harness from a dropdown.

Reviewing an agent’s output in one pane

A redesigned editor panel in the Agents window folds the editor and the detail area into one docked pane with a shared tab bar. Files and diffs open next to the chat, and a Changes view supports inline and side-by-side diffs, expanding or collapsing every file at once, and a compact diff layout that fits more of a change on screen.

The next step,