Connor Peet from the VS Code team explains the Agent Host Protocol, a new open protocol designed to decouple AI agent sessions from individual VS Code windows. The protocol enables long-running agent sessions that persist across window closures, synchronize state across multiple clients and machines, and handle reconnections gracefully. Inspired by the Language Server Protocol and Debug Adapter Protocol, it aims to be IDE-agnostic so any client or harness can plug in. VS Code ships a local agent host by default, but users can also connect to remote hosts via SSH, WSL, or tunnels — including the vscode.dev/agents web interface. The protocol also supports multiple AI harnesses (Copilot, Claude Code SDK, Codex) simultaneously. Future directions include multi-chat orchestration within sessions, cron-job-style agent triggers, and deeper extensibility APIs for developers to script their own agent workflows.