Your First AI Context File: What to Write, Step by Step

The first time you use an AI tool for your business, you get back something technically fine and completely off-brand. The email sounds like a company, not like you. The caption sounds like your whole industry, not your corner of it.

The AI is capable. It has just never met your business before.

The fix is a short file you write once. It tells the AI about your business, your voice, your customers. You load it once and it is there at the start of every chat, automatically, so you stop re-explaining yourself from scratch every time.

That file is a context file. This guide walks you through writing your first one.

What a context file actually is

Think of it as the orientation note you would write for a sharp new hire on their first morning. They can do almost anything you ask. But they showed up knowing nothing about you, your customers, or how you like to sound on email.

A quick intro would do it. The business, the customers, the voice, the things to avoid. A page or two. You hand it over before they answer their first call.

A context file is exactly that, for your AI. You write it once, you paste it into the tool you use, and your AI starts every task already oriented to your business.

If you have ever wondered why AI forgets your business the second you open a new chat, how context files actually work covers the mechanics in plain English. You do not need it to follow this guide, but it is a good next read.

Five sections

A simple context file has five short sections. None of them require any technical skill. The whole thing fits on one page and takes about an hour the first time.

1. Who you are and what you do

Two or three sentences. The business name, what it does, where it operates.

Example: "Riverbend Gallery is an independent art gallery in Portsmouth, NH. We represent regional painters and printmakers and sell original work and prints directly to collectors and interior designers."

Keep it factual. This is an orientation note, so plain description beats sales copy every time.

2. How you sound

Spend the most time here. It makes the biggest difference.

Real examples do the work. "Warm and direct" means almost nothing to an AI, because it has read a million pages that also called themselves warm and direct. One sample email or two sentences about what you would never say is worth far more.

Example: "I write the way I talk. Short sentences. First names, not 'valued customer.' I never say 'reach out' or 'at your earliest convenience.' If a word feels stiff, I cut it. Here is an example: 'Hey Maria, your piece is in and it looks great. Come by any time Thursday or Friday and I will have it ready for you.'"

For a fuller walkthrough of building this section out, How to Train ChatGPT on Your Business's Voice walks through the whole process, including how to pull examples from writing you have already done.

3. Who your customers are

A short sketch of the person you are usually writing for. What they care about, what they already know, what they worry about.

Example: "Most of my customers are buying art for the first time, or for a specific room or occasion. They are not collectors by identity. They want to feel good about the choice and confident the piece will be taken care of. Price matters but it is not the first thing on their mind. Reassurance is."

A short sketch is enough. You just want the AI writing to a real person instead of a generic one.

4. What you sell and what you will not say

List your actual offers in plain language, then add a short list of things you do not do or would not claim.

Example: "We sell original paintings ($800–$4,000), limited prints ($150–$600), and framing as an add-on. I do not do commissions and I do not promise delivery dates I have not confirmed. I will not call a piece an investment. I will not quote prices in writing without a current check of availability."

This section keeps the AI from inventing things you do not offer and from using claims you would never stand behind.

5. The context for what you are asking today

Leave this section blank in the standing file. Fill it in when you start a specific chat.

Example: "Today I am writing a follow-up to a customer who looked at a piece on Saturday and said they would think about it."

Some things are specific to a moment. This slot is a reminder to add that context right when you open a chat, so you do not forget it.

Where to put it

Once you have written the file, it needs a home. Here is where to put it in each of the major tools, in plain English:

• ChatGPT: go to Settings, then Personalization, then Custom Instructions. Paste your context there. Every chat you open will start with it loaded.
• Claude: create a Project (you will see it in the left sidebar). Paste your context into the Project Knowledge section. Every chat you open inside that project starts with it already there.
• Gemini: create a Gem and add your context to the instructions. Same idea, different name.

If you would rather skip the setup for now, paste the whole file at the top of a chat before your first request. It works for that session, and it is a good way to test how well your file is working before you commit to a permanent home for it.

A few things to leave out

Keep your customers' private information out of the file. Their contact details, order history, anything financial, anything told to you in confidence. You can teach the AI how you sound and who you serve without any of that. When in doubt, leave it out.

Also skip anything that changes quickly, like a seasonal promotion or a current sale price. Those are better added in the moment than baked in and forgotten.

When to update it

Once a season, a few minutes. Look it over when something shifts: you added a service, your tone tightened, you started turning down a type of request you used to take. The file is only as useful as the last time you touched it.

A calendar reminder on the first week of each new quarter takes care of it. The update is always faster than the original write.

The shortcut

If sitting down to write this feels like one more thing on a list that is already too long, that is exactly what Business Brain is for.

It walks you through the five sections as a guided conversation, pulls the relevant parts from your existing site and writing, and hands you a finished file ready to drop into ChatGPT, Claude, or Gemini. One time, fifty dollars, yours to keep.

Either way, you only have to explain your business once. After that, your AI already knows.