AI tool comparison
DOOM MCP vs OpenCode
Which one should you ship with? Here is the side-by-side panel verdict, pricing read, reviewer split, and community vote comparison.
Developer Tools
DOOM MCP
Play DOOM inline inside Claude or ChatGPT — full game, no browser needed
75%
Panel ship
—
Community
Free
Entry
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.
Developer Tools
OpenCode
The open-source AI coding agent that works with 75+ models
75%
Panel ship
—
Community
Free
Entry
OpenCode is a fully open-source AI coding agent built by Anomaly that runs in the terminal, desktop, and IDE — and connects to more than 75 LLM providers including Claude, GPT, Gemini, and local models. It currently has over 140,000 GitHub stars and 850 contributors, making it one of the fastest-growing open-source developer tools of 2026. Unlike vendor-locked coding agents, OpenCode lets developers bring their own subscriptions (ChatGPT Plus, GitHub Copilot) or connect local models through LM Studio. It supports the Agent Client Protocol (ACP) for broad IDE compatibility — JetBrains, Zed, Neovim, Emacs, VS Code, and Cursor — and emphasizes a privacy-first architecture that never stores your code or context data. The optional Zen tier provides a curated, benchmarked set of AI models specifically optimized for coding workflows, offering a premium experience without locking users into a single cloud provider. With an Early Bird period ending April 14, OpenCode is rapidly becoming the go-to open alternative to Claude Code and Copilot for developers who want control over their stack.
Reviewer scorecard
“The signed-token progressive enhancement pattern is the part worth stealing. This is a clean reference architecture for MCP interactive apps, and DOOM just happens to be the demo case.”
“140K stars isn't hype — OpenCode has real momentum because it solves the actual problem: vendor lock-in. I can use my existing Claude subscription, switch to a local Gemma model when I need privacy, and have it work in every IDE I already use. This is what the coding agent space needed.”
“Fun proof of concept but let's be honest: if your AI assistant is hosting a DOOM session, something has gone wrong with your productivity. The MCP-as-interactive-surface insight is real, but this specific app has no utility.”
“The 'works with 75 models' pitch sounds great until you realize most of those models are dramatically worse at coding than Claude or GPT-5. The premium Zen tier is where the real value likely lives, and we don't know what that costs yet. Wait to see how Zen pricing shakes out before committing.”
“Every major compute platform's pivot point is when it runs DOOM. MCP running DOOM means MCP is a real platform now. The implications for interactive AI-embedded experiences are significant.”
“OpenCode is the Mozilla Firefox moment for AI coding tools — an open-source reference implementation that keeps the big players honest on privacy and portability. The Agent Client Protocol integration points toward a future where your coding agent context travels across every tool in your workflow seamlessly.”
“As someone who thinks about interactive experiences, the idea of game-like UI living inside an AI context is genuinely exciting. This is a crude ancestor of what interactive AI-native media could become.”
“The multi-session and shareable session link features are underrated for creative teams. Being able to share an in-progress coding session with a designer or content collaborator without spinning up another subscription is genuinely useful. Privacy-first matters a lot when working with client IP.”
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