DOOM MCP vs MCPCore

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.

MCPCore is a browser-based platform that collapses the full lifecycle of Model Context Protocol server development — writing, testing, deploying, and managing — into a single interface. You describe what you want your MCP server to do in plain English, and an AI generates the server code. One-click deploy pushes it to an instant subdomain. No Dockerfile, no Kubernetes, no infrastructure decision-making. The platform covers four authentication modes (Public, API Key, OAuth 2.0, Bearer Token), AES-256 encrypted secret management for API keys and credentials your server needs at runtime, and ready-made configuration exports for every major MCP client: Claude Desktop, Cursor, VS Code, Windsurf, and Cline. A usage dashboard tracks calls, errors, and latency. The free tier allows one server and 10,000 calls per month. As MCP adoption accelerates — with Anthropic, OpenAI, and the Linux Foundation all standardizing around the protocol — the bottleneck is shifting from "what can MCP do" to "who can actually build and host MCP servers." MCPCore is a direct answer to that bottleneck: it brings MCP server creation within reach of developers who can write JavaScript but have never configured a cloud deploy pipeline.