DOOM MCP vs TUI-use

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.

TUI-use is an open-source library that gives AI agents the ability to interact with traditional interactive terminal (TUI) applications — think vim, htop, ssh sessions, database CLIs, and legacy text-based UIs that were never designed for programmatic control. Instead of requiring a GUI or a REST API, TUI-use interprets terminal output as structured state and sends synthetic keystrokes back, enabling agents to "see" and "drive" any TUI application as if they were a human at a keyboard. The project was born from a real pain point: AI coding agents can call bash commands and write files, but they fail badly the moment a tool opens an interactive prompt waiting for user input. TUI-use solves this by building a state machine layer over PTY (pseudo-terminal) interfaces, letting agents read the current screen buffer, detect interactive prompts, and respond intelligently. It ships with adapters for common TUI patterns and a clean API that works with any LLM tool-use framework. The Show HN post attracted genuine interest from the ops and DevOps community — many existing workflows depend on tools that expose only an interactive terminal interface. TUI-use fills a real gap in the "AI agents that control computers" space by handling the long tail of CLI programs that have no API, no GUI, and no intention of ever getting one.