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Evaluate

The Evaluate page runs an LLM-as-a-judge pipeline to score a prompt/response pair across five quality dimensions, then lets you auto-optimize the prompt to address weaknesses.

Overview

Evaluating prompt quality subjectively is hard — what "good" means varies by context. The Evaluate tool uses an LLM as a judge: it sends your prompt and the model's response to a second LLM call that analyzes and scores the output across five structured categories.

This is a common pattern in production LLM systems where automated quality assurance is needed at scale.

How to use

  1. Paste the prompt you used (the input you gave the model) in the left panel
  2. Paste the model response you received in the lower left panel
  3. Click Run Judge
  4. Read the scorecard on the right — each category gets a score from 1–5 with a justification
Note
You can evaluate any prompt/response pair — it doesn't have to come from PromptLab. Copy-paste from ChatGPT, Claude, or any LLM output.

Score categories

CategoryWhat it measures
ClarityIs the response easy to understand? Is it well-structured and unambiguous?
RelevanceDoes the response directly address what was asked?
CompletenessDoes it cover all aspects of the request, or does it leave things out?
CreativityIs there original thinking, novel framing, or insightful elaboration?
ConsistencyIs the response internally consistent — no contradictions or logical gaps?

Each score is 1–5. The Executive Summary at the top gives an overall assessment in plain language.

Auto-Optimize

After receiving scores, click Auto-Optimize. This triggers a second LLM call that reads your original prompt, the response, and the scorecard — then rewrites your prompt to address the weak scores.

The optimized prompt replaces the content in the Prompt Context panel so you can immediately re-evaluate.

Tip
Run Auto-Optimize multiple times iteratively. Each round should improve scores. If a category is stuck at a low score, add explicit constraints in the system prompt targeting that dimension.

Interpreting scores

  • 5 / 5 — Excellent. The response fully satisfies this criterion
  • 4 / 5 — Good. Minor improvements possible
  • 3 / 5 — Acceptable. Noticeable gaps — worth addressing
  • 2 / 5 — Weak. The prompt likely needs restructuring
  • 1 / 5 — Poor. The response fails this criterion significantly

Focus optimization effort on the lowest-scoring categories. A score of 3 or below in Relevance usually means the prompt is too vague — the model didn't understand what you wanted.