# zrak

> zrak runs AI coding agents in parallel on your computer. Each one works in its own git worktree, on the model you pick, and its changes reach your checkout only when you apply them. Free. Agents use your AI Models Router credits, or your own API key.

zrak (always lowercase, said "zrahk": Czech and Slovak for "sight") is a free desktop app by AI Models Router.
Release status: Windows: in final testing · macOS and Linux: coming. No download is published yet; https://zrak.ai/download reads the release feed live and shows the installer, its version, size and SHA-512 once it is out.

## What it does

- Many agents. Each in its own worktree. One worktree and branch per agent; 8 at once by default, up to 32; Up to 4 subagents at once per agent, nested under it with the whole tree's spend; Agents keep working in the tray when you close the window.
- You decide what runs. Three approval modes: Ask every time (Commands wait for your approval, one at a time. Allow once, allow for the session, or deny.) Smart (Read-only and test commands run. A small model reviews the rest and runs only the steps it is at least 90% sure are safe; everything else waits for you.) Full auto (Agents run their steps without asking, except the actions listed below, which wait in every mode.) In every mode, Full auto included, these wait for your click: Pushing, Publishing, Deploying, Payments, Email, Deleting or writing outside the agent's worktree, MCP tools a server marks destructive.
- Review every change, with evidence. The Review screen shows an agent's diff for its last turn, for all its edits, for uncommitted work or for its whole branch. Keep or revert single changes, send line comments back to the agent, and see the evidence: test results from the commands it ran, cost and time. Run the same task on other models and compare up to four agents side by side. Apply checks for conflicts before it touches your checkout.
- Describe the outcome. Watch the score. Describe what the finished product does. zrak breaks it into yes/no features, each with a locked test, and shows how many pass. It can then run on its own toward 100% until it reaches the budget and time limit you set, and it stops early after repeated failures.
- runs: on your computer; agents keep working in the tray when you close the window; code: agents edit in their own git worktrees; your checkout changes when you click Apply; keys: encrypted with your operating system's secure storage; the window only sees a masked preview; prompts: not stored on our servers; AI Models Router records tokens, cost and status, not content; telemetry: none: no analytics, no crash reports; models: AI Models Router, or any OpenAI-compatible endpoint and key; updates: installed only when signed with our release key.
- Free. You pay only for model usage. Prepaid AI Models Router credits at the per-token prices shown before you pick a model, or your own key with any OpenAI-compatible endpoint.

## FAQ

- What is zrak? A free desktop app for running many AI agents in parallel. Each agent works in its own git worktree, on the model you pick; you approve what matters and apply its changes when they are right. It is made by AI Models Router.
- Is zrak free? Yes. The app costs nothing. Agents use model credits on your AI Models Router account, or your own API key with any OpenAI-compatible endpoint.
- Which platforms does it run on? The Windows release is in final testing. macOS and Linux builds are not available yet.
- What else do I need? Git, because every agent works in a git worktree. On Windows, commands run in Git Bash from Git for Windows when it is installed, otherwise in Windows PowerShell.
- Which models can agents use? Any model in the AI Models Router catalog, with its price and context length shown when you pick it, or Auto, which picks one for each agent by cost, balance or quality. You can also bring any OpenAI-compatible endpoint and key.
- Does my code leave my computer? Agents send what each step needs to the model API you chose; that is how a model reads your code. AI Models Router records tokens, cost and status for each request, not its content, and zrak sends no telemetry, analytics or crash reports.
- Does it work offline? The app runs on your computer, but agents need a model API to work.
- How do updates work? zrak checks for updates every 4 hours, downloads them in the background and installs them when you click Restart to update or the next time you quit. It installs only releases signed with our release key. Choose Stable or Beta in Settings → App.

## Links

- [zrak](https://zrak.ai/): product page
- [Download](https://zrak.ai/download): release status and downloads
- [AI Models Router](https://aimodelsrouter.ai): the API and credits zrak uses by default
- [Models and prices](https://aimodelsrouter.ai/models)
- [Terms](https://aimodelsrouter.ai/legal/terms), [Privacy](https://aimodelsrouter.ai/legal/privacy)