VS Code March 2026 Update Brings Native Copilot Agent Mode and Multi-Root Workspace AI

Microsoft has released Visual Studio Code 1.99, the March 2026 update, featuring the most significant upgrade to GitHub Copilot integration since the AI assistant was first embedded in the editor. The headline feature is native Copilot Agent Mode — a capability that allows Copilot to autonomously plan, execute, and verify multi-file code changes across entire workspaces, moving beyond the single-file inline suggestions that defined its first generation.

Agent Mode

Copilot Agent Mode transforms the AI assistant from a reactive suggestion engine into a proactive coding partner. When activated, the agent can analyze a task description, create a plan spanning multiple files, execute the changes, run tests to verify correctness, and iterate on failures — all with minimal developer intervention. The agent has access to the terminal, file system, and debugging tools, enabling it to perform tasks like "add authentication to this API" that require coordinated changes across controllers, middleware, configuration files, and tests.

Agent Mode operates within a sandboxed environment that prevents it from making changes outside the current workspace or executing destructive system commands. Every action the agent takes is logged and can be reviewed, approved, or reverted through a new "Agent Timeline" panel in the editor.

Multi-Root Workspace AI

The update also brings Copilot awareness to multi-root workspaces — a feature that monorepo developers have been requesting since Copilot's launch. In previous versions, Copilot's context was limited to the currently open file and its immediate imports. The March update enables Copilot to understand the relationships between projects in a multi-root workspace, providing suggestions that correctly reference shared libraries, common types, and cross-project dependencies.

Inline Chat Improvements

Inline chat — the ability to give Copilot natural language instructions within the editor — has been enhanced with scope controls. Developers can now scope their instructions to specific files, functions, or symbols, telling Copilot to "refactor this function to use async/await" or "add error handling to all API calls in this file" with precise targeting. The scoping system integrates with VS Code's existing symbol navigation, so developers can use the same @-mention syntax they use for workspace search.

VS Code 1.99 is available now through the standard update mechanism. Copilot Agent Mode requires a GitHub Copilot subscription (Individual, Business, or Enterprise).