AI Commands: Rewrite Any Text in Any App, Instantly

Select text in any desktop application — email, IDE, document editor, Slack, or terminal — press your AI hotkey, and Lightning Assist rewrites, enhances, translates, or summarises it in place. No browser tab. No copy-paste.

Lightning Assist AI Commands are the only desktop-native, system-wide AI rewrite tool that works in every app on Windows, macOS, and Linux — select text, press a hotkey, AI rewrites it in place.

Part of the AI writing assistant — the cross-platform productivity app for Windows, macOS, and Linux.

What Are AI Commands?

AI Commands are Lightning Assist's inline AI feature: select any text, press a configured hotkey, and choose a command — Rewrite, Improve, Make concise, Translate, Fix grammar, or a custom command you define. The selected text is replaced by the AI output, directly in the application where you are working.

The result appears in place without any context switching. You do not need to open a browser, paste into ChatGPT, copy back, and reformat. The workflow stays in your current application, at your current cursor position.

What You Can Do With AI Commands

  • Rewrite and improve: make a drafted paragraph cleaner, clearer, or more professional without rewriting it yourself.
  • Make concise: condense a long email, a wordy comment, or a verbose paragraph to its essential point.
  • Translate: translate selected text to another language without leaving the application you are in.
  • Fix grammar and spelling: correct errors in a draft without manually editing each sentence.
  • Custom commands: define your own AI instructions — summarise as bullet points, extract action items, convert to formal tone — and trigger them with a dedicated hotkey.
  • Works system-wide: email clients, code editors, document editors, messaging apps, browser text fields — AI Commands work wherever you can select text.

How AI Commands Work

  1. Select any text in any application on your desktop.
  2. Press your configured AI hotkey (customisable in settings).
  3. A command palette appears — choose a built-in command or a custom one you defined.
  4. Lightning Assist sends the selected text to the AI, along with your instruction.
  5. The AI response replaces the selected text, in place, in the same application.

AI Commands in Action

Selected text: the thing we need to do is make sure that all the required fields are filled in before the form gets submitted to the backend server

After Make concise: Validate all required fields before submitting the form to the backend.

Selected text: Hi I wanted to follow up on the email I sent last week about the project status

After Improve: Following up on my email from last week regarding the project status. Please let me know if you need any additional information.

Selected text: The API returns a 429 when you hit the rate limit. You should back off and retry.

After Translate to French: L'API renvoie un 429 lorsque la limite de taux est atteinte. Vous devriez temporiser et réessayer.

AI Credits

AI Commands use AI Credits — purchased separately from the base subscription. Credits are consumed only when you run a command. You are never charged automatically.

  • No recurring AI charge: buy a credit pack when you need it; unused credits carry over.
  • Starter credits included: new accounts receive free AI Credits to try AI Commands without buying a pack first.
  • Transparent cost: each command consumes a small, fixed number of credits — you always know what you are spending.

Updated for 2026: Related guides

Try AI Commands Free

14-day free trial, all features included — text expansion, AI Commands, and push-to-talk voice. No credit card. Windows, macOS, and Linux.

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Frequently Asked Questions

What desktop apps do AI Commands work in?

AI Commands work in any desktop application where you can select text: email clients, code editors (VS Code, JetBrains, Cursor), document editors (Word, Google Docs in a browser), Slack, Teams, and every other tool. Lightning Assist operates at the OS level, not as a browser extension.

Do I need an OpenAI account or API key?

No. AI Commands use Lightning Assist AI Credits, which you buy through the Lightning Assist dashboard. There is no need to create or manage a separate AI provider account.

How is this different from pasting into ChatGPT?

With ChatGPT you select text, copy it, switch to a browser tab, paste, prompt, copy the response, switch back, and paste again. AI Commands remove every step except selecting the text and pressing the hotkey. The result appears in place in the same application, with no context switching.

Can I define custom AI instructions?

Yes. You can create custom AI commands with your own instruction — for example, 'summarise as three bullet points' or 'convert to formal business English' — and assign each one a hotkey or a label in the command palette.

How is AI Commands different from the AI Features page?

The AI Features page covers all Lightning Assist AI capabilities, including AI Speech (push-to-talk voice) and AI Credits. The AI Commands page focuses specifically on the inline text rewriting feature — select text, hotkey, AI rewrites in place.

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