Alex Hancock

goose now supports lifecycle hooks. Drop a plugin into a directory on disk and goose will run your shell scripts when things happen during a session: a tool is about to fire, a tool just finished, the user submitted a prompt, the session started, the session ended.

If you've used Claude Code's hooks or git hooks, it's the same idea. If you haven't: the agent loop is now scriptable from the outside, without writing any Rust or any MCP server.

goose started life in the terminal. The earliest versions were a Python CLI that ran the agent in-process — you typed a message, the model responded, tools executed, and everything happened in a single loop. That simplicity was a strength: it meant anyone with a terminal could start using goose immediately, no app to install, no server to run.

As goose grew, so did the ways people wanted to use it. We shipped an Electron desktop app and suddenly we had two clients with two completely different integration paths. The Rust CLI talked to the agent directly in process, while the desktop app went through goosed, a custom REST + SSE server. Every new feature — session management, extension loading, streaming — had to be wired up in both places.

There is an emerging approach to MCP tool calling referred to as "sandbox mode" or "code mode". These ideas were initially presented by Cloudflare in their Code Mode: the better way to use MCP post and Anthropic in their Code execution with MCP: Building more efficient agents posts. Since the approach and the benefits are clearly laid out in those posts I will summarize them here.