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AI only knows what you tell it (and other things I learned the hard way)

Sep 30, 2026 · by Stella Noelle

AI only knows what you tell it (and other things I learned the hard way)

Most of the time AI "fails," it isn't dumb. It's guessing, because I didn't give it what it needed. Before I hit enter, I check three things.

1. Who is it?

Tell it what role to play: "You are my chief of staff," "You are a patient editor." One sentence changes the whole answer.

2. What does good look like?

Give the format, the length and an example if you have one. "Four sections, bullets under 20 words" beats "make it clear" every time.

3. What's the context it can't see?

Your working hours. Your customer. The fact that your boss hates jargon. If it isn't in the prompt, AI doesn't know it.

My favorite line to add to any prompt: "Ask me up to 3 questions if anything important is missing."

Try it

Pick one prompt you use a lot and add those three things. Then tell me what changed: @stelnoelle.

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