Verifying frontend changes always meant a mental context switch: write code, alt-tab to a browser, poke around in DevTools, switch back. Even with a decent dev server, the loop was still manual — and for AI agents, it was essentially broken. Agents could write unit tests for logic, but verifying whether a button actually renders, whether a dialog triggers, or whether a layout holds up? That required a human in the loop. I first tried to tackle this problem by using the Playwright or Chrome Dev-Tools MCP server, but with the February 2026 release of VS Code (1.110) , that changes. Agents can now open, interact with, and inspect your running application directly inside VS Code's integrated browser — closing the development loop without any manual hand-off. How it works When browser agent tools are enabled, Copilot gains access to a set of tools that let it read and interact with pages in the integrated browser. As the agent interacts with the page, it sees updates to page co...