For Mac
A desktop AI agent for Mac
Vassal Agent is a desktop AI agent for Mac: an app with its own Chromium browser where an AI does web work for you, such as research, lists, form filling and outreach drafts, signed in as you. It runs on your Mac rather than in someone else's cloud, uses the AI plan you already have, and asks before it sends, posts, pays or deletes anything.
Why a desktop app instead of a cloud agent or an extension?
AI agents come in three shapes. Cloud agents run a browser on the vendor's servers, so you have to hand them your logins or sign in again inside their browser. Extensions live inside your everyday browser, next to your personal accounts. A desktop agent is an app on your own computer with its own browser.
| Desktop app (Vassal Agent) | Browser extension | Cloud agent | |
|---|---|---|---|
| Where the browser runs | On your Mac | On your computer, in your everyday browser | On the vendor's servers |
| Whose logins it uses | The work sites you sign in to in the app | Everything signed in to your browser | Whatever you sign in to in their browser |
| Separate from personal browsing | Yes | No | Yes |
| Sites see | Your own computer and connection | Your own computer and connection | A data-center connection, which some sites block |
| Runs while your computer is off | No | No | Yes |
The trade-off is plain: a desktop agent needs your Mac to be on, and in return your logins never leave it and sites see an ordinary person on an ordinary connection.
What can it do on a Mac?
- Research and lists. "Find twenty accounting firms in Ohio with fewer than fifty people, with the managing partner's name and a link." It returns a table with a source for each fact.
- Forms and data entry. Fill CRMs, portals and applications from a sheet or an email, and stop at Submit. See automating web forms.
- Outreach drafts. Write a first note to each person in your voice, and wait for your Allow on every send.
- Monitoring. Watch a page, a job board or an inbox and tell you what changed.
- Workflows on a schedule. Do a job once while it watches; it becomes a workflow that runs daily, on a page change or when a new email arrives.
Which AI does it use?
Yours. The built-in assistant runs on your Claude plan, and Claude Pro at $20 a month is enough. ChatGPT's Codex, Gemini, Cursor, Claude Desktop and other tools that speak MCP can also connect and drive the same browser. See Claude browser automation.
Is it safe to give an AI my Mac's browser?
The agent only works in the app's own browser, never your personal one. Before it sends, posts, submits, pays or deletes, the app stops and asks, and that check runs outside the AI, so a page that tries to trick the model still cannot press the button. Every action is logged. Read the full safety model.
How do I get started?
Download Vassal Agent for Mac, connect your AI with one button, and type your first job. The first 7 days are free with no card; after that it is $499 a month or $4,990 a year, with a setup call and one custom workflow built with you. See pricing.
Questions
Which Macs does Vassal Agent run on?
Macs with Apple silicon (M1 and later) and Intel Macs. The download page picks the right version for your Mac.
Is there a Windows version?
Not yet. A Windows version is in the works; the download page will offer it as soon as it is ready.
Does my Mac need to stay on?
Yes, for jobs to run. The agent works in the browser on your Mac, which is why it can use the sites you are already signed in to. It keeps running in the background when you close its window.
Is it a Chrome extension?
No. It is its own Mac app with a Chromium browser inside. It does not touch your personal Chrome or Safari.
Does it send my data to Vassal Agent?
No. The app has no analytics or telemetry. Your browsing, logins, chats and activity log stay on your Mac. The page content the AI reads goes to your own AI provider under your account.
How do I install it?
Download it from the download page, open the file, and drag Vassal Agent into Applications. On first open, macOS asks once whether to open it.
See it on your own work.
Try it free for 7 days with no card. After that it is $499 a month or $4,990 a year, with a private setup call and one custom workflow built with you.