Vibe Coding · レッスン

プロンプトを反復改善する

最初からやり直さず、段階的にAIを方向づけます。

レッスン 4/413 ステップ

「プロンプトを反復改善する」はCoddyKit上の無料Vibe Codingレッスンです。これはレッスン4/4です。下記で完全なレッスンを無料で読むことができます。その後、ブラウザ内の組み込みコードエディタと24時間対応のAIチューターでハンズオン演習できます。これはVibe Coding学習パスの一部であり、ウェブとCoddyKitアプリ全体で進捗が同期されます。 Vibe Codingコースには全4レッスンが含まれています。

このレッスンの一部はまだ翻訳されておらず、英語で表示されています。

The First Answer Is a Draft

Beginners often delete everything and start over when the AI's first try isn't perfect. Pros do the opposite: they iterate. They treat the first output as a draft and steer it with follow-up messages.

This is the rhythm of real vibe coding — refine, don't restart. This lesson teaches you how to nudge the AI toward exactly what you want, step by step.

The Iteration Loop

Every build follows a simple loop:

Prompt — ask for something
Run — preview the result in Bolt, v0, or your editor
React — note what's right and what's off
Refine — give a focused follow-up

You repeat this loop a few times per feature. Each pass gets you closer.

Refine, Don't Restart

The AI remembers the conversation. So you don't re-describe the whole app — you just say what to change. This keeps everything you already liked.

Restarting (wasteful):
  "Build the whole todo app again but with bigger buttons."

Refining (smart):
  "Make the Add button bigger and move it to the right of
   the input."

Change One Thing at a Time

When you ask for five changes at once, it's hard to tell which fix helped and which broke something. Iterate in small steps so you can see the effect of each one.

Step 1: "Change the theme color to purple (#7c3aed)."
   (check it looks right)
Step 2: "Now add a subtle hover effect to the buttons."
   (check again)
Step 3: "Now make it work on mobile widths."

Point to What's Wrong

Good iteration feedback names the specific thing that's off and what you want instead. 'It's bad' gives the AI nothing to work with.

Weak feedback:  "That's not right, try again."

Strong feedback: "The list items are cramped. Add more vertical
                  space between them and a thin divider line."

Keep What Works

When part of the output is great, say so and protect it. Telling the AI what to keep stops it from rewriting code you already liked during the next change.

"The layout and colors are perfect — keep those exactly.
 Only change this: when the list is empty, show the text
 'No tasks yet. Add one above!' centered in gray."

Iterating on Logic, Step by Step

Iteration works for behavior too. Start with a basic version, then layer on rules. Here's a greeting function after one refinement step — try running it.

// Step 1 result: a simple greeting
// Step 2 refinement: "also handle an empty name"
function greet(name) {
  if (!name) return 'Hello there!';
  return 'Hello, ' + name + '!';
}

console.log(greet('Sam'));
console.log(greet(''));

When to Restart Instead

Iteration is the default — but sometimes a fresh start is faster. Restart when:

The code has become a tangled mess after many edits
You realize the approach is fundamentally wrong
The AI is stuck in a loop, re-breaking the same thing

In that case, write a clean new prompt that includes everything you learned.

Roll Back Bad Steps

Sometimes a refinement makes things worse. Don't try to patch a patch — go back. Most tools let you undo: Cursor and Claude Code track edits, and Git lets you revert to a known-good version.

A clean rollback plus a sharper prompt beats five rounds of damage control.

"That last change broke the layout. Undo it and go back
 to how the page looked before. Then instead, just
 increase the font size of the headings to 24px."

Give Feedback in the AI's Language

Speed up iteration by reacting to concrete things: the live preview, an error message, or a screenshot. Many builders like v0 and Lovable let you click an element and say 'change this'.

The more precisely you point, the fewer rounds you need.

Fast iteration cues:
- "See the red error in the console? Fix that."
- "The button I just clicked — make it full-width."
- "Match the spacing to the screenshot I shared."

A Real Iteration Session

Here's how a few turns of refinement feel in practice. Each message is short because the AI remembers the rest.

You: "Build a tip calculator: bill input, tip % buttons, total."
AI:  (produces it)
You: "Add a 'split between N people' field."
You: "Round each person's share to 2 decimals."
You: "Keep all that — just make the total bold and bigger."

Quick Check

The AI's first version of your app is 90% right — the layout is great but one button is the wrong color. What's the best next move?

対話的なレッスンで答える

Recap: Steer, Don't Restart

Great vibe coding is a conversation, not a single command:

Treat the first answer as a draft
Run the prompt → run → react → refine loop
Change one thing at a time, point to what's wrong
Keep what works; roll back bad steps
Restart only when the approach is truly wrong

You've now mastered the core of prompting: structure, specificity, context and iteration. You're ready to build your first real app by talking to AI!

無料で開始

AI チューターと学ぶ JavaScript — 無料

ブラウザでリアルコードを書いて実行し、24/7 の AI チューターから瞬時にサポートを受け、ウェブまたはアプリで続きから学習できます。

コース: 25
レッスン: 100

無料で学習を始めるコース全体を表示

よくある質問

「プロンプトを反復改善する」レッスンは無料ですか？

はい。「プロンプトを反復改善する」の完全なテキストはこのウェブで無料で読めます。インタラクティブに演習し（組み込みコードエディタと24時間対応のAIチューター）、Vibe Codingコースの残りをアンロックするには、CoddyKit PROにアップグレードしてください。 Vibe Codingコースには全4レッスンが含まれています。

「プロンプトを反復改善する」で何を学びますか？

最初からやり直さず、段階的にAIを方向づけます。ブラウザで直接実行するハンズオンコードでVibe Codingを演習し、24時間対応のAIチューターがレッスンを進める中での質問に答えます。

Vibe Codingを始めるのに経験は必要ですか？

事前経験は必要ありません。CoddyKitのVibe Codingは初級者から上級者向けに構成されているため、ここから始めるか最初から始めて、自分のペースで進むことができます。これはレッスン4/4です。

「プロンプトを反復改善する」レッスンにはどのくらい時間がかかりますか？

ほとんどのCoddyKitレッスンは約5～10分かかります。各レッスンはコンパクトでインタラクティブなので、着実に進歩し、ウェブとアプリ全体で正確に前回の場所から再開できます。

このVibe Codingレッスンでコードを書いて実行できますか？

はい。すべてのVibe Codingレッスンに組み込みコードエディタが含まれているため、ブラウザでリアルコードを書いて実行し、即座のAIフィードバックを取得できます。ローカル設定は不要です。

このコースのすべてのレッスン

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