Plan the cleanup of a messy phone number column

About this exercise

You're importing your salon's client list into a texting tool that only accepts 10 digits with no symbols, like 6145550142. Ask for exactly 5 numbered cleanup steps, each one plain sentence: work in a new column so the originals stay, and flag (don't delete or guess) any row that doesn't end with exactly 10 digits. Plain text, under 110 words.

Common mistakes when you ask AI for this

• Editing the original column. The AI rewrites the column in place, so you can't check its work. Try: Add: "Work in a new column; keep the originals."
• Not giving the target format. The AI picks a nice-looking format like (614) 555-0142, which the tool rejects. Try: Add: "Final format is 10 digits, no symbols, like 6145550142."
• Letting the AI guess. The AI adds an area code to short numbers or deletes rows it can't fix. Try: Add: "Flag any row without exactly 10 digits. Don't delete or guess."
• Getting a formula essay. The AI writes long nested formulas with explanations. Try: Say: "Exactly 5 numbered steps, each one plain sentence."
• Getting markdown back. AI bolds step names and adds headings. Try: Ask for "plain text, no bold."

What a strong prompt includes

• Keeps the originals
• Gives the target format
• Says to flag, not guess
• Sets the number of steps
• Asks for plain text

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