Run ChatGPT in Any Mac App with a Keyboard Shortcut

The ChatGPT desktop app for Mac has a global hotkey that opens a window. That window is its own conversation. To use ChatGPT on something you wrote in another app, you copy from your app, switch to ChatGPT, paste, type a prompt, wait, copy the result, switch back, paste. Five context switches for one rewrite.

There is a faster path. TypeFire lets you bind a keyboard shortcut to an AI snippet that runs ChatGPT on your selection, in place, in whatever app you are typing in. No window switch.

This post walks through how to set that up, the prompts to start with, and where this beats the official ChatGPT app.

What it looks like in practice

You are writing a Slack message that came out clumsy. Highlight your draft. Press your shortcut. The polished version replaces it. You hit send. Total time: about two seconds.

Or: you got a long email from a customer. Highlight the email body. Press a different shortcut. A summary in bullets replaces it where you can read it without scrolling. Or: an English message you want to send in French. Highlight, press, French version replaces the English one.

The keyboard shortcut runs OpenAI's API on whatever you have selected and pastes the result back. You stay in your app the whole time.

Setup, in five minutes

1. Get an OpenAI API key. Sign up at platform.openai.com and add a payment method. OpenAI requires prepaid credits to use the API at all (a $200/month ChatGPT Pro subscription does not include API credits, separate product). $5 in credits is plenty; thousands of typical rewrites.
2. Install TypeFire from typefire.app. Free, native macOS, signed and notarized.
3. Add your key. Open Settings, AI tab, paste your OpenAI key, pick a model (gpt-4o-mini is the fastest and cheapest), click Test. The dot turns green.
4. Create a rewrite snippet. New snippet, body just {{ai:rewrite:professional}}, no abbreviation needed. Assign a global keyboard shortcut to it (Cmd+Ctrl+R works well, but anything you do not already use is fine).
5. Try it. In any app, highlight a draft, press the shortcut. Polished version replaces your selection.

That is the loop. Repeat for any other transformation you want as a shortcut: summarize, translate, fix grammar, custom prompts.

A handful of useful starter prompts

These are real snippets people set up on day one. Each gets its own keyboard shortcut.

Polish for professional contexts (Cmd+Ctrl+P)

{{ai:rewrite:professional}}

Use for: emails to clients, PR communications, meeting notes that someone else will read.

Casual rewrite (Cmd+Ctrl+C)

{{ai:rewrite:casual and warm}}

Use for: Slack messages, replies in friendly threads, internal team comms.

Bullet summary (Cmd+Ctrl+B)

{{ai:summarize:as 3-5 short bullet points, key points only}}

Use for: condensing long docs, meeting transcripts, customer emails.

Fix grammar only (Cmd+Ctrl+G)

{{ai:fix}}

Use for: when you wrote it the way you wanted but want spelling and grammar cleaned up without rephrasing.

Translate to a language (different shortcuts per language)

{{ai:translate:French}}

Replace French with any language. You can have one snippet per language, or use the custom action with a placeholder.

Custom anything

{{ai:custom:turn this into a Slack standup-style update with three sections: yesterday, today, blockers}}

The text after the second colon is a free-form instruction. Anything you can describe to ChatGPT works.

Why this beats opening the ChatGPT app

The official ChatGPT desktop app is the right tool when you want a conversation. It is the wrong tool when you want a one-shot transformation. The official app forces a context switch every time. TypeFire keeps your hands on the keyboard and your eyes on the document you were already in.

There is also a privacy difference. TypeFire is bring-your-own-API-key. The key sits in your local config file on your Mac. Every API call goes directly from your Mac to OpenAI's API. TypeFire's servers see nothing. No proxy, no logging.

What about Claude or Gemini?

Same flow. TypeFire supports all three providers. Claude (claude-sonnet-4-6 is a strong default) costs about the same as OpenAI per token and gives different output quality. Gemini has a free tier and is the cheapest path if you want to try the feature without any commitment. You pick the active provider in Settings, AI tab; switching takes one click.

For an in-depth take on the free path, see Free AI Text Expander for Mac.

The two-second test

Download TypeFire, paste an OpenAI key, set up {{ai:rewrite}} with a keyboard shortcut. Highlight your next outgoing message, press the shortcut. Either you keep using TypeFire from that day forward, or you do not. The bar to find out is genuinely two minutes of setup and one keystroke.