Prompt Evaluator

Evaluate LLM prompts on a 100-point scale based on research findings from Thorgeirsson et al. (2026), which demonstrated that writing quality—specifically coherence, instructional clarity, and information content—significantly predicts LLM-assisted programming performance.

Key Research Insights

• Information content > vocabulary: Adding missing information improves results; rewording without adding information rarely helps (Lucchetti et al.)
• Structure matters: Unorganized, vague prompts lead to failure cycles
• Declarative > interrogative: Declarative statements outperform questions (Chen et al.)
• Ambiguity kills: Unclear pronouns, implicit assumptions, and missing constraints are top failure causes

Evaluation Workflow

1. Receive the user's prompt
2. Read references/evaluation-rubric.md for detailed scoring criteria
3. Score each of the 5 axes (4 sub-items × 5pt = 20pt per axis, 100pt total)
4. For common issues, consult references/improvement-patterns.md for Before/After examples
5. Output the evaluation result using the template below
6. Provide a revised prompt

5 Evaluation Axes

Output Template

Use this exact template because a consistent format helps the user easily compare evaluations and understand the scoring breakdown:

## プロンプト評価結果 / Prompt Evaluation

### 対象プロンプト
> [quote the evaluated prompt here]

### スコア

| 軸 / Axis | スコア | 主な所見 |
|-----------|--------|----------|
| 明確性 (Clarity) | __/20 | ... |
| 構造 (Structure) | __/20 | ... |
| 情報量 (Info Content) | __/20 | ... |
| 特定性 (Specificity) | __/20 | ... |
| 文脈提供 (Context) | __/20 | ... |
| **合計 / Total** | **__/100** | |

### 評価の概要
[1-2 paragraph summary of strengths and weaknesses]

### 改善提案
1. [specific, actionable suggestion]
2. [specific, actionable suggestion]
...

### 改善版プロンプト
[the improved prompt in a code block]

Scoring Guidelines

• 0pt: Sub-item is completely absent or counterproductive
• 1pt: Minimal attempt, mostly insufficient
• 2-3pt: Partially addressed, room for improvement
• 4pt: Well addressed with minor gaps
• 5pt: Excellent, no meaningful improvement needed

Language Handling

• Evaluate prompts in any language (Japanese, English, etc.)
• Output the evaluation in the same language as the user's prompt
• Scoring criteria apply universally regardless of language