Google quietly added something helpful this week. Gemini in Google Docs now lets you set custom instructions. You set them once. Gemini follows them every time you use it.

It sounds like a small change. But it will save a lot of people a lot of time.

The Problem It Solves

If you use AI writing tools often, you know the frustration. You open a new document, start chatting with the AI, and spend the first few messages just re-explaining what you want. “Keep it short.” “Use bullet points.” “Don’t use passive voice.”

Every. Single. Time.

Gemini in Docs now lets you skip all of that. Set your instructions once in the side panel. Gemini will follow them in every session, in every document. You can save up to 1,000 instructions.

What You Can Do With This

There are lots of ways to use this. Here are a few simple examples:

For writers and content teams: Lock in your brand voice. Tell Gemini your style once. It will stick to it.

For client work: Set different rules for different clients. Always formal for Client A. Always short summaries for Client B. Gemini will remember.

For technical writers: Set rules for headings, terms, and product names. No more fixing the same things over and over in every draft.

For non-native English speakers: Set your tone and grammar rules up front. Every suggestion will be closer to what you want from the start.

How to Set It Up

There is no settings menu to find. Just open the Gemini side panel in any Google Doc. Type your instruction directly into the chat. Something like “always end summaries with three key points” or “use a friendly but professional tone.” Gemini saves it and uses it going forward.

The 1,000-instruction limit is very generous. Most people will never get close to it.

Who Gets Access

The rollout started on May 4, 2026. Google says it will reach all users within 15 days. It is available to:

• Google Workspace Business and Enterprise customers
• Google AI Plus, Pro, and Ultra subscribers

You do not need to ask your IT team to turn it on. You can set it up yourself.

The Bigger Picture

Google has been working hard to make Gemini more useful across all of Workspace. Earlier this year, they updated the “Help me create” tool in Docs. They also improved the “Match writing style” feature. And they gave Gemini better access to your Drive, Gmail, and Calendar.

Custom instructions fit right into that plan. The idea is simple. An AI that already knows how you work is more useful than one you have to teach every time.

Other AI tools like ChatGPT and Claude already do this. Users like consistency. Having to repeat yourself gets old fast.

One Thing to Watch Out For

These instructions apply to all your documents. They are not smart enough to change based on the type of document you are writing. If you write in very different styles for very different purposes, one set of rules might not cover everything.

For more control, Google’s Gems feature lets you build custom AI setups for specific tasks. But Gems are not built into Docs in the same way yet.

For most people, though, this is a real time-saver. Set your rules once and let Gemini do the rest.

Custom instructions for Gemini in Google Docs began rolling out on May 4, 2026, and will reach all eligible users within 15 days.

Custom instructions fit that pattern. The goal isn’t to make Gemini smarter — it’s to make Gemini more