Four lines that change the output.
Most people use Claude like a search bar. Type a question, get an answer, hope it's good. That works some of the time. The rest of the time the answer is generic, off-topic, or wrong.
Four extra lines fix it. This guide is those four lines, plus a side-by-side that shows what they actually do.
You're typing one line. You need four.
When you give Claude one line, you've handed it almost no information. It has to guess who you are, who the answer is for, what shape you want, and what you don't want. It guesses fast. It often guesses wrong. The output looks generic because the input was generic.
The fix isn't a clever phrase or a magic word. The fix is structure. Four lines, every time.
What to add before the wall of text.
These four lines go in front of every prompt. They take 30 seconds to write. They change the output more than any other single thing you can do.
Reader
Who is this for. Be specific. "My boss" beats "someone." "A first-time customer who hasn't heard of us" beats "a customer."
Shape
What the output should look like. Three bullet points. Five versions. A 200-word paragraph. A subject line plus a body.
Style
The tone. Plain. Formal. Casual but not sloppy. Like a friend, like a press release, like a teacher, like a doctor. Pick one.
Avoid
The one thing you don't want. Jargon. Long preambles. Em dashes. Hype words. The negative tells Claude almost as much as the positive.
The structure that works on almost everything.
Reader: [who reads this] Shape: [3 bullets, 5 versions, 200 words, etc.] Style: [tone, voice] Avoid: [the one thing you don't want] [paste the raw material here]
Paste this at the top of any new Claude prompt. Replace the bracketed parts.
What the lines do, with the same task.
Say you're writing a follow-up email after a sales call.
Same Claude. Same minute of your life. Different output.
Common traps.
- Writing a vague Reader. "A customer" is not a reader. "A customer who's used us once and hasn't come back" is a reader.
- Skipping Shape and then complaining the answer is too long. Claude wrote until it ran out of things to say. Tell it when to stop.
- Writing five negatives in Avoid. One is enough. More than one and Claude starts twisting itself in knots.
- Pasting the raw material before the four lines. Order matters. The lines set the frame. The frame shapes the read.