5 Common Mistakes in AI Custom Instructions

Mistake #1: Being Too Vague

The most common mistake we see is instructions that are too general to be useful.

The problem: "Help me write better" gives AI nothing to work with.

The fix: Be specific about what "better" means to you. "Write in short, punchy sentences. Avoid passive voice. Always lead with the most important information."

Mistake #2: Forgetting Negative Constraints

People focus on what they want but forget to specify what they don't want.

The problem: You keep getting responses with emoji when you hate emoji. Or AI keeps using "utilize" when you prefer "use."

The fix: Add explicit constraints. "Never use emoji in professional communications. Avoid words like 'utilize,' 'leverage,' and 'synergy.'"

Mistake #3: Ignoring Context

Your instructions should reflect your current professional situation, but many people write generic instructions that could apply to anyone.

The problem: Generic instructions produce generic outputs.

The fix: Include your industry, role, and current goals. "I'm a product manager at a fintech startup. I frequently communicate with engineering teams and external stakeholders. Help me be clear and concise."

Mistake #4: Setting It and Forgetting It

Your career evolves. Your instructions should too.

The problem: Instructions you wrote six months ago might not reflect your current role, goals, or communication style.

The fix: Review and update your instructions quarterly, or whenever you have a significant career change. Got promoted? Changed industries? Update your instructions.

Mistake #5: Making Instructions Too Long

There's a sweet spot for instruction length. Too short and they're not useful. Too long and key details get lost.

The problem: A 2,000-word instruction set where the important bits are buried in paragraphs of text.

The fix: Keep instructions focused and scannable. Use clear sections. Prioritize the most important rules. If something isn't materially affecting your outputs, cut it.

The Quick Fix Checklist

Before finalizing your custom instructions, ask yourself:

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