DOOM MCP vs King Louie

Chris Nager built a fully playable DOOM that runs as an MCP (Model Context Protocol) app, rendering inline inside Claude and ChatGPT without a separate browser tab. The architecture uses two MCP tools — create_doom_session for inline-capable hosts and get_doom_launch_url as a browser fallback — combined with cloudflare/doom-wasm for the game runtime and a signed token system that maintains session state across both surfaces. The result is the same session whether you're playing inline or in a tab. The key technical challenge was avoiding iframe and CSP (Content Security Policy) issues. Rather than embedding a browser page inside the MCP iframe, the DOOM canvas runs directly inside the host's iframe — a subtle but critical distinction that resolved a class of rendering and input-handling bugs. The final implementation is intentionally stripped down: no save/load, no persistence adapters, just stable playable DOOM. Beyond the novelty, this project is a concrete demonstration that MCP apps are interactive surfaces, not just tool-calling JSON endpoints. The progressive enhancement pattern — same signed-token foundation serving both inline and browser modes — is a reusable architecture for any game or interactive experience that wants to live inside an AI assistant. Nager open-sourced the implementation and the blog post is a detailed technical breakdown.

King Louie is an open-source, cross-platform AI agent desktop app built on Electron. You bring your own API keys for your preferred LLM provider, and King Louie provides the full stack: cron scheduling for recurring agent tasks, semantic memory with embedding-based tiering and recall, voice/TTS (via system TTS or ElevenLabs), webhooks for external automation triggers, and syntax-highlighted markdown rendering. Builds ship for Windows (NSIS), macOS (DMG), and Linux (AppImage/DEB). The agent framework ships three preconfigured agents: a general-purpose assistant, a code explorer, and a code writer. All agents run in an agentic loop, with the orchestrator supporting parallel, serial, and dependency-based multi-agent execution. You can also connect King Louie to Telegram, Discord, and Slack as a bot — turning a single local install into a presence across every platform you communicate on. King Louie fills a real gap: most AI agent tools require cloud accounts, usage fees, or sending your data to third-party infrastructure. For developers, privacy-conscious power users, or anyone who wants an AI assistant that runs entirely on their own hardware with their own keys, this is the most fully-featured local-first option currently available. The MIT license means you can extend, self-host, and redistribute freely.