FullStacked vs Harness Code

Create, run and share projects built with web technologies in a fully cross-platform, local-first environment.

Harness Code turns your computer's AI coding agents into a native phone experience. Start threads with Claude Code, Codex, or the built-in Harness engine — which brings 300+ models to your fingertips through your own OpenRouter key, no CLIs required. Watch replies stream live with full markdown, review the diffs and files your agents produce, answer their questions with a tap, and get a push notification when a long task finishes — from anywhere, over your own private Tailscale network. Built for real remote control, not just notifications. There's no cloud relay to lag, disconnect, or sit between you and your agent — your phone talks straight to your own computer over your private network. Sessions live on the computer, so nothing is lost if your phone sleeps or you drive through a tunnel: reopen the app and pick up exactly where the agent is. Steer mid-task, queue follow-ups, approve or deny actions, switch models and permission modes — everything you could do at the desk, from your pocket. Your computer does the work; your phone is the remote. Harness Code connects only to the harness server you run on your own Mac or Windows PC. No accounts, no middleman, no data leaves your devices. - Three engines: Claude Code, Codex, or the built-in agent with 300+ models via OpenRouter - Multiple concurrent threads, each with its own engine, model, and working directory - Streaming replies with markdown, code blocks, and tool-activity timelines - Reasoning summaries, per-message token/cost readouts, and usage-limit tracking - Preview HTML, PDFs, images, and code your agents create - Voice dictation, image attachments, slash commands, permission modes - Approve or deny agent actions remotely — even ones triggered by scheduled automations - Archive, search, drafts, and deep-linked push notifications Requires: a Mac or Windows PC running the free harness server (60-second install from harness-site.vercel.app). Bring your own AI: the Claude Code or Codex CLI signed into your subscriptions, an OpenRouter key, or all three. Not affiliated with Anthropic or OpenAI. Try Demo mode in-app to explore without a computer.