Lesson 15 of 1570
Iterate, Don't Rewrite
Beginners scrap their prompt and start over. Pros keep the good parts and change only what isn't working. Here's how to iterate like a craftsperson.
Lesson map
What this lesson covers
Learning path
The main moves in order
- 1The rewrite trap
- 2iteration
- 3prompt versioning
- 4A/B comparison
Concept cluster
Terms to connect while reading
Section 1
The rewrite trap
When a prompt gives a bad output, the temptation is to throw it out and type a fresh one. Don't. The first prompt probably had 80% of the right stuff. You just need to fix the 20% that's off.
The diagnostic loop
- 1Run the prompt. Look at the output.
- 2Identify exactly what's wrong (too long? wrong tone? missed a constraint?).
- 3Change only the part related to that problem.
- 4Run again. Compare.
- 5If it got worse, undo. If it got better, keep going.
Version diary example
Four versions, each isolating one change.
v1: Write a product description for a reusable water bottle.
→ Output: Generic marketing speak.
v2 (added audience): Write a product description for a reusable water bottle targeting eco-conscious college students.
→ Output: Better but still too 'ad-like.'
v3 (added role and tone): You are a copywriter for a zero-waste brand. Write a product description for a reusable water bottle. Tone: warm, punchy, no clichés like 'game-changer.'
→ Output: Much better. Reads like a real brand.
v4 (added format): ...as v3, but output with a hooky headline, 2 short body sentences, and 3 bullet features.
→ Output: Ready to ship.Each version changed one thing. That means if v3 was much better than v2, you know it was the role-and-tone addition. If you had changed three things at once, you wouldn't know what helped.
Keep a prompt notebook
- Save prompts that worked, with a note on what task they solved.
- Save prompts that failed, with a note on what broke.
- Steal from your past self. The template you tuned last month is gold.
Key terms in this lesson
End-of-lesson quiz
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