Your text, only better. Everywhere.
Select text in any macOS app, press a shortcut: Claudio proofreads, translates, summarizes or rephrases it — and pastes the result right back in place. No window switching, no copy-pasting.
macOS 14+ · Apple Silicon · Free, with your own Anthropic API key
⌃⌥E on a selection → the panel pops up next to your pointer, the result streams in live, and ⏎ pastes it in place.
Features
Proofread, translate, summarize, rephrase… Every action has its own reconfigurable global shortcut, and its prompt can be edited in Settings.
Spelling, grammar and slightly improved phrasing — language and tone preserved. Perfect after voice dictation.
Natural, idiomatic translation with formatting preserved.
Draft in your language, send in English — emails, messages, documentation.
Turns a blunt draft into a clear, courteous message that's ready to send — without changing what it says.
A few faithful sentences or bullet points, depending on length. Great for digesting a long thread or article.
Rewrites a rough idea as a clear, direct request for an AI — without answering it.
Produces a full prompt following best practices: role, context, constraints, expected output format.
How it works
A word, a paragraph, a whole email — in Mail, Safari, Slack, Notes, your IDE… anywhere.
Hit the shortcut for the action you want. The panel appears next to your pointer and the result streams in, without stealing focus from your window.
⏎ replaces the selection with the result and restores your clipboard. Esc cancels, ⌘C just copies.
Why Claudio
A real macOS menu bar app: lightweight, instant, with no Electron and no hungry background processes.
Your API key lives in the macOS Keychain. Selected text goes straight to Anthropic — no middleman server, no account, no telemetry. And the code is open source: anyone can check where their key goes.
Every shortcut is reconfigurable and every system prompt is editable in Settings. Make Claudio your own.
Powered by Claude Haiku: the answer streams in as it's written, and one action costs about 0.2¢ on your API key.
Install
Notarized build in the works — meanwhile, the app builds with a single command from the source.
FAQ
Claudio is free and open source (MIT license). You use your own Anthropic API key, billed per use: a short proofread or translation costs about 0.2¢ — even heavy use stays within a few dozen cents a month. And if the app earns its keep, you can buy me a coffee.
Straight from your Mac to the Anthropic API, over HTTPS. Claudio has no server, no account, no database: nothing is stored or read by anyone else.
It's the official macOS mechanism for reading selected text in another app and simulating the paste. Without it, Claudio can neither capture your selection nor replace it.
Anywhere text can be selected: Mail, Notes, Pages, Safari, Chrome, Slack, IDEs… Claudio reads the selection through the Accessibility API and falls back to a simulated copy for apps that don't expose it (your clipboard is restored afterwards).
Yes, both. Every action has a reconfigurable shortcut and an editable system prompt in Settings — with a button to restore the original.
Because an assistant this devoted deserved a first name — and a mustache.