Usami
Usami is a small native menu-bar app for macOS under MIT. Select text anywhere, click the floating star icon that appears beside it, and improve, rephrase, translate or custom-edit the selection with a Claude or ChatGPT subscription you already pay for. The project is 2,000 lines of Swift and SwiftUI with no third-party dependencies, no server, no analytics and tokens kept in a private file on the Mac.
What does Usami do?
Usami's README introduces it as "a small native macOS menu-bar app: a system-wide AI writing assistant that works like a grammar checker and rewriting tool in every app." Select some text in Mail, Slack, Notes, a browser or an editor, click the star icon that appears beside the selection, pick Improve, Rephrase, Translate, one of the More options, or describe your own change under Custom, and the selection is replaced in place when you Accept.
The README says Usami uses the Claude Pro, Max, ChatGPT Plus or Pro subscription you already pay for, through the browser sign-in flows for each. Claude requests run through the official claude CLI, which the README says needs to be installed. The project is built in Swift and SwiftUI, about 2,000 lines of code with no third-party dependencies, no server and no analytics. Only the selected text is sent, only to the provider you picked.
Key facts
- Licence: MIT, per the README's own badge and the LICENSE file.
- macOS 14 Sonoma or newer, Apple Silicon and Intel.
- Install with
curl -fsSL https://raw.githubusercontent.com/raousama391/usami/main/install.sh | bash, or downloadUsami.dmgfrom Releases. - Subscriptions supported: Claude (Pro and Max) and ChatGPT (Plus and Pro), through browser sign-in. The README says Claude requests "run through the Claude Code CLI, so it needs to be installed."
- Accessibility access is required so Usami can read the text in a selection.
- Translates into 14 languages, per the README.
- Several cards at once, per the README: a card can stay open in one app while another is open in a different one.
- No server and no analytics; tokens stay on the Mac in "a private, owner-only file."
- The README states Usami is "about 2,000 lines of Swift, no third-party dependencies."
What does it replace, and where does it fall short?
Usami replaces Grammarly for a Mac user who already pays for Claude Pro, Max, ChatGPT Plus or Pro, and wants a lightweight "fix this selection" box in every app without a second subscription. It is a candidate on the open-source alternatives to Grammarly page.
Where it falls short: Usami is deliberately small, with no inline underlines as you type and no plagiarism check (the README names these directly). Grammarly covers Windows, web and mobile; Usami is macOS only. Someone without a Claude or ChatGPT subscription has no path to use it, so a non-subscriber should pick Lexa, which routes to free hosted providers or local models.
How does Usami run?
Install Usami from the shell script or the DMG. On first launch, a setup guide asks you to choose Claude or ChatGPT and a model, sign in through your browser, and enable Accessibility access. Reopen the guide any time from Settings. The README states no server component, and the single install produces the whole product.
Updates come optionally from GitHub Releases: get notified, install automatically or never check, per the README.
Who is Usami for?
A Mac user who already pays for Claude or ChatGPT and wants Grammarly-shaped rewriting as a system-wide trigger. For a wider set of providers (Groq, Gemini, Ollama, LM Studio), Lexa.
What limits does the README state?
- macOS only.
- Accessibility access is required.
- "Real-time underlines & plagiarism check: No" (per the Usami versus Grammarly table in the README).
- Claude requests need the Claude Code CLI installed.
Questions people ask
Is Usami open source?
Yes. The LICENSE file is MIT, verified on the date on this page. The README also states "Open source: MIT-licensed, about 2,000 lines of Swift, no third-party dependencies." MIT is an OSI-approved licence with no added conditions.
Does Usami need a paid subscription?
Yes. The two signed-in routes are Claude (Pro or Max) and ChatGPT (Plus or Pro), as the README states. Without one of those, there is no documented path to use Usami. Lexa is a nearby project that supports free hosted keys and local models.
Does Usami send my text to the cloud?
Yes, to the provider you chose, and only when you trigger a rewrite. The README says "only the text you choose to rewrite is sent, only to the provider you picked", and "tokens stay on your Mac in a private, owner-only file."
How does Usami compare with Grammarly?
The README has its own table: Usami is free (uses an existing Claude or ChatGPT plan), is open-source MIT, keeps the text with the provider you chose, needs no account with the app's vendor, is macOS only, and does not do inline underlines or plagiarism checks. Grammarly covers more surfaces at a subscription price. The open-source alternatives to Grammarly page compares the two.
How many languages does Usami translate into?
Fourteen, per the README. The default language can be changed in Settings.
Sources
- Usami README and MIT LICENSE: github.com/raousama391/usami, read 2026-10-19.
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Added October 19, 2026. Every claim above comes from the project's README, LICENSE or model card, read on October 19, 2026, or from the GitHub API on the date shown in the panel. Found an error? Write to reveneau@licheo.com and it is fixed in the next weekly pass. Repository: github.com/raousama391/usami.
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