You type, context is read on-device
As you write in any text field, Shadowtype reads the surrounding text locally through macOS accessibility — never by uploading it anywhere.
AI writing assistant · macOS
An AI writing assistant for Mac —
An AI writing assistant for Mac —
completion and rewrite, fully on-device.
Shadowtype is a complete writing assistant that runs a real language model on your Apple Silicon chip — not in the cloud. It does two things everywhere you type: it finishes your sentences as inline ghost text (Tab a word, ⌥Tab a line), and it rewrites text you select with ⌥⌘K — improve, shorten, make formal, make casual, fix grammar, or summarize. All of it is local, private, and free and open source.
What a full writing assistant looks like
Two ways to write faster
Most writing tools do one thing. Shadowtype covers the whole arc of writing — drafting the next words for you, then reshaping what you’ve already written — and it does both without your text ever leaving the Mac. Here’s the loop.
Ghost text predicts your next words
A GGUF model from the built-in catalog (Qwen3 Base, Gemma 3, MoE variants — or bring your own) runs via llama.cpp + Metal and shows the continuation as dimmed inline text. Tab accepts a word, ⌥Tab a whole line.
Select & rewrite with ⌥⌘K
Highlight any text and press ⌥⌘K to pick an action — improve, shorten, make formal, make casual, fix grammar, or summarize — and Shadowtype rewrites it in place, on-device.
It learns your voice
Add per-app instructions and let it adapt to your phrasing over time, plus emoji shortcodes (:smi → 😄) and multiple languages — all without sending a byte off-device.
Everything it does
A writing assistant, not a single trick
Inline completion, everywhere
A real LLM predicts your next words as ghost text in Mail, Slack, Notes, your editor, the browser — anywhere you type. Tab accepts a word, ⌥Tab a whole line, and it’s pure local autocomplete.
Selection rewrite on ⌥⌘K
Highlight a sentence, paragraph, or email and press ⌥⌘K to improve, shorten, make formal, make casual, fix grammar, or summarize. The rewrite runs on-device and replaces your selection in place.
Emoji & multi-language
Type :smi and get 😄 inline. Write in English (sharpest), Norwegian, Hinglish, and more — the model completes and rewrites in the language you’re already typing.
Personalized to your voice
Give per-app instructions — a crisp voice for Mail, looser for Slack — and let Shadowtype adapt to your phrasing over time. Your tone, not a generic model’s.
100% on-device & private
Completion and rewrite both run locally with llama.cpp + Metal — no cloud call ever. Private by design with zero telemetry and no account, and it keeps working offline.
Free, not a subscription
Shadowtype is free and open source. There’s no monthly fee and no server to fund — use it on as many of your Macs as you like.
Local API + MCP for developers
An OpenAI-compatible HTTP endpoint runs on 127.0.0.1 so your scripts, editors, and agents can call the same on-device model — no key, no cloud. A built-in MCP bridge plugs into Claude Code and other MCP clients, and the BYOM picker loads any GGUF.
Beyond cloud writing assistants
A full assistant that happens to be local
Cloud writing assistants stream your drafts to a server and bill you monthly for the privilege. Shadowtype gives you the same breadth — drafting, rewriting, summarizing, tone control — but runs the whole model on your machine and personalizes to you locally, sending nothing off-device. If you’re comparing it to the built-in option, see how it stacks up vs Apple’s Writing Tools, or read the full feature list.
Questions
AI writing assistant FAQ
What can the AI writing assistant do?
Two core things, everywhere you type. It completes your sentences as inline ghost text — Tab accepts a word, ⌥Tab a line — and it rewrites text you select on ⌥⌘K: improve, shorten, make formal, make casual, fix grammar, or summarize. It also expands emoji shortcodes (:smi → 😄), writes in multiple languages, and personalizes to your voice with per-app instructions.
Is it on-device and private?
Yes. Both completion and rewrite run 100% on-device with llama.cpp + Metal on Apple Silicon — no cloud inference call ever. Unlike cloud writing assistants, your text is never transmitted. Shadowtype ships with zero telemetry, needs no account, and works fully offline, so privacy is the default.
Does it work in any app?
Yes. Completion and rewrite work system-wide through macOS accessibility — Mail, Slack, Notes, your code editor, the browser, anywhere you can type. You can even set per-app instructions so it uses a different tone in Mail than in Slack.
Is it a subscription?
No. Shadowtype is free and open source. No monthly fee, no account, no server to fund — all inference runs on your own Mac. Use it on as many of your Macs as you like.
Can my own scripts, editors, and agents use the same local model?
Yes. Shadowtype exposes an OpenAI-compatible HTTP endpoint on
127.0.0.1 with no key required, so your terminal, editor plugins, and AI agents can call /v1/chat/completions against the same on-device model. A built-in MCP server plugs into Claude Code and other MCP clients, and the BYOM picker loads any GGUF you drop in. Everything is bound to localhost — nothing leaves your Mac.
Ready when you are
A writing assistant that runs on your Mac, not someone’s server.
Download Shadowtype free, accept your first word with Tab, rewrite a paragraph with ⌥⌘K, and upgrade once — never monthly.
- 100% on-device
- No subscription
- No account
- Zero telemetry
- Open source