Block Goose: The Open-Source, Model-Agnostic AI Coding Agent Changing the Game in 2026

Block — the company behind Square and Cash App — just open-sourced something worth paying attention to: Goose, a model-agnostic AI coding agent that runs locally, connects to any LLM, and doesn't lock you into a single vendor's ecosystem. In a landscape dominated by Cursor ($20/month, Claude-or-GPT-only) and GitHub Copilot ($19/month, OpenAI-dependent), Goose is a genuinely different approach: bring your own model, run your own agent, own your own data. For AI-assisted development learners, Goose represents something important — the open-source wave catching up to the commercial tools, and doing so on more flexible architectural terms. Here's what Goose actually does, how to set it up, and when it makes sense to use it over the commercial alternatives.