DOOM MCP vs Kontext CLI

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.

Kontext CLI is a Go binary that wraps AI coding agents — currently Claude Code — with enterprise-grade credential management. Instead of storing long-lived API keys in .env files your agent can read and potentially leak, you declare what credentials your project needs in a .env.kontext file using placeholders like {{kontext:github}}. When you run 'kontext start', it authenticates via OIDC, exchanges placeholders for short-lived scoped tokens via RFC 8693 token exchange, injects them into the agent's environment, and streams every tool call to an audit dashboard. When the session ends, credentials expire automatically. The .env.kontext file is safe to commit — no secrets, just declarations. Written in Go with zero runtime dependencies. Solves a real but underappreciated security gap: AI agents with access to long-lived credentials are high-value targets for prompt injection and confused deputy attacks.