Is there an AI that writes replies in any app on Mac?
The short version: Yes. Opsis writes your next line wherever you type: Slack, Gmail, Outlook, Teams, Notion, Google Docs and AI chats like Claude and ChatGPT. Press Tab to keep it. It can also draft a whole reply from a few notes, using facts from your own work: what's on your screen, the apps you connect (Gmail, Calendar, Drive, Slack, Notion, GitHub, Linear, Outlook) and your history. On Mac it works across your apps and the browser: type, see the suggestion, press Tab. Opsis runs on Mac and Windows. It's free to start, and Pro is $15 a month.
Several Mac tools offer system-wide completion as of November 2026, including Cotypist, Typeahead and Caret. What sets Opsis apart is the second half of the job: drafting a full reply from your notes with facts from connected apps and your history, and having the same product on Windows.
How it compares.
System-wide AI writing tools for Mac, as of November 2026
| Tool | How it works | Windows | Uses connected apps and history |
|---|---|---|---|
| Opsis | Tab-to-keep completion plus full reply drafts from notes. Cloud processing with consent. | Yes. | Yes: Gmail, Calendar, Drive, Slack, Notion, GitHub, Linear, Outlook. |
| Cotypist | Local AI autocomplete in your voice, in apps across your Mac. Apple silicon only. | Not available. The site offers a waitlist. | Not described on its site. |
| Typeahead | Local, system-wide autocomplete for Mac. Tab accepts. | Not listed. | Not described in listings. |
| Caret | Reads what is on your screen and offers Tab-triggered completions on macOS. | Not listed. | Not described in listings. |
Swipe the table to compare
Figures and shutdown dates come from the sources at the bottom, or from this site's own product copy. We don't invent competitor features.
Who it's for.
Mac users who write in more than two apps a day and want one tool, not a different extension in each.
Your data.
Opsis only follows the apps you share. Private windows and password managers are never recorded. When assistance is on, the text it needs is processed in the cloud with your consent, encrypted in transit and at rest, with zero data retention at our AI providers. Opsis isn't a screen recorder. You can pause, disconnect an app or delete your history whenever you like. Read the privacy policy · How Opsis handles data.
Local versus cloud, said plainly
Cotypist and Typeahead describe local processing, which keeps text on your Mac. Opsis processes text in the cloud when assistance is on, with your consent. That is what lets it draft long replies and use facts from connected apps. If nothing may leave the machine, a local tool is the right pick.
Honest limits
The Typeahead and Caret details come from third-party directories, so check their own sites for current information. Opsis supports Apple silicon Macs.
FAQ
What is the best system-wide AI autocomplete for Mac?
It depends what you value. For fully local, Cotypist and Typeahead are described that way. For drafting full replies with facts from your work, and the same tool on Windows, try Opsis.
Does Opsis work on Intel Macs?
Opsis ships for Apple silicon Macs and 64-bit Windows.
Does it work in every app?
It works in the apps you share, including Slack, Gmail, Outlook, Teams, Notion, Google Docs and AI chats. Some apps limit what any tool can read or write.