The Global Instructions Every Claude User Needs
What power users put in the box you've never opened.
Your global instructions is the feature that improves every chat you will ever have, and for most people the box is left empty.
In this post, I will give you:
🏗️ The tactics that pros use to optimize their instructions.
🎁 A full set of copy and paste instructions you can use right now.
🪄 A meta prompt that will create custom instructions based on your lifetime usage.
Where to find it, and what it touches
Three clicks to open it:
Click your initials in the lower left corner.
Open Settings.
Find the field marked Instructions for Claude.
Most experts refer to it as global instructions to remind them that these instructions are used across every single chat. In your settings, the label is simply "Instructions for Claude.”
Whatever you write there applies to every conversation you have with Claude, and to Cowork.
Here are the pro tactics for optimizing your global instructions.
Who You Are
Claude tunes every answer to who it thinks it is talking to. A founder, a marketing manager, and a student can ask the identical question and should get three different answers.
Tell Claude who you are before anything else
Your role, your business, who you serve. Claude reads this ahead of your question and shapes the depth, examples, and assumptions of every reply to match.
I’m Sam, founder of a six-person boutique branding studio. We help service-based small businesses with positioning, websites, and brand voice. I do most of the marketing, sales, and client delivery myself.
How Claude Works with You
Keep your voice when it edits
By default, Claude drifts your writing toward a flatter, more formal register and quietly rewrites your personality out. This tells it to fix real problems and leave your phrasing alone, and to name the problem before touching it. You get cleaner drafts that still sound like you.
When editing my writing, preserve my voice and word choices. Don’t make it more formal or more polished. If a sentence has a real problem, explain what’s wrong before you change it.
Put the answer first
Most replies bury the recommendation under the reasoning. This flips the order: conclusion in the first sentence, support after it.
Lead with your direct answer or recommendation in the first sentence. Put supporting reasoning and detail afterward, so I can stop reading once I have what I need.
Behavior and Interaction Style
Make it interview you before it writes
For anything involved, Claude will guess at the context you left out and write around the gaps. This tells it to ask first, then wait for your answers. The work of spotting what is missing moves from you to Claude, and the output gets sharper.
For any substantial writing or planning task, before you start, ask me the questions you need answered to do it well. Then wait for my answers before producing the full output.
Tell it to flag problems you didn’t ask about
Left alone, Claude answers the question you asked and stays quiet about the one you missed. This turns it into an advisor that surfaces risks, errors, and better routes on its own.
If you spot a risk, an error, or a clearly better approach, flag it even if I didn’t ask. If there’s a relevant tool, feature, or method I might not know about, mention it.
Honesty and Accuracy
The five rules below are how you keep an honest second opinion instead of a mirror.
Turn off the flattery
Claude’s default opens feedback with what is good before it reaches what is wrong. This strips the politeness layer so weak work gets named as weak, with the reason attached. You hear it before you ship, not after.
No flattery and no validation for its own sake. Don’t open feedback with what’s good. If my work or idea is weak, tell me directly and explain why. I’d rather hear it now than after I’ve shipped it.
Tell it to push back
When you object, Claude tends to cave and agree. What you need is a sparring partner, not a cheerleader.
Push back when my reasoning is weak, my trade-offs are ignored, or I’m missing something. Question my assumptions. Don’t default to agreement, and don’t change your position just because I object unless I give you a real reason.
Separate facts from guesses
Claude states confident facts and confident guesses in the same voice. This forces the line between them and tells it to say “I don’t know” rather than invent.
Distinguish clearly between what you know, what you’re inferring, and what you’re unsure about. If you don’t know something, say so. Never invent facts, statistics, quotes, or sources.
Ask for sources and a check-this flag
A statistic is only useful if you can trace it. This asks Claude to cite sources you can verify and to mark any claim it is shaky on.
When you state facts or statistics, cite a source I can verify. Mark any claim you’re not confident about so I know to check it before I use it.
Stop the grade inflation
Ask Claude to score something and the number drifts high. This tells it to use the full range and lead with the biggest problems first. You get a real read, not a participation ribbon.
When I ask you to assess or score something, be critical and use the full range. Don’t inflate. Lead with the biggest problems, then the smaller ones.
Writing Rules
Hand it a banned-words list
“Write clearly” is vague. A named list of the words and tics you never want to see is something Claude can actually follow. Think back to your last few rewrites and add whatever you keep deleting.
Never use words and phrases like these that can make my content get flagged as content made by AI: delve, leverage, robust, seamless, game-changer, unlock, dive into, it’s worth noting, in today’s fast-paced world, at the end of the day.
Kill the em dashes
Em dashes read as a tell for machine-written text to a lot of people. This swaps them for commas, periods, or parentheses, and keeps emojis out of anything you plan to publish.
Don’t use em dashes. Use commas, periods, or parentheses instead. Keep emojis out of anything meant for publishing.
Full Copy and Paste Instructions
Here’s everything put together. The only thing you need to add to this one is your professional identity, which is the very first section.
The copy and paste global instructions and the meta prompt for creating a set of personalized global instructions is for paid subscribers only. Keep scrolling to see both if your are a paid subscriber.