You write the prompt. I do what you said. If you don’t like what I did, consider what you said.

Ford

This isn’t a prompt template gallery. You won’t find “10 prompts that will change your life.” The Lab lets you see what your prompt actually tells the model — and how changing your words changes what you get.

You’ll see two things below your response: the model’s thinking summary (what it reports thinking before it responds) and a structured framing analysis (what a separate model identifies as your prompt’s framing). Both are useful. Neither is a brain scan.

If this is your first time here: type a question the way you normally would. Don’t try to be clever. The point is to see what happens with a normal prompt — and then what changes when you improve it.

Try a starter prompt:
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Thinking and analyzing…
Response
Marvin

Revise Your Prompt
What role should the model adopt?

A cautious analyst and an enthusiastic advisor will give you different answers to the same question.

What is the output for?

A memo to your team, a first draft you’ll rewrite, and a checklist you’ll follow are three different specifications.

What should be excluded?

Telling the model what NOT to do is often more useful than telling it what to do.

What does success look like?

If you can’t describe what a good answer looks like, the model can’t produce one.

How much confidence should the model express?

Asking the model to flag uncertainty is the single most underused technique in professional prompting.

There are questions up here that might help you write a better prompt. Or you could figure it out yourself. I have no preference either way.

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Thinking and analyzing…
Revised Response
Marvin

The Source Shelf
Ford

You don’t need a $30 book on prompt engineering. The companies that built these models publish free documentation telling you exactly how to use them. It gets updated when the models change. Books don’t. The Lab helps you practice what the documentation teaches — and these are the docs.

Anthropic (Claude)
Prompting Best Practices

The living reference for all Claude prompting techniques. Start here.

Prompt Engineering Overview

Entry point with links to interactive tutorials and console tools.

Context Engineering for Agents

Advanced guidance on treating context as a finite, engineered resource. Directly supports how this site thinks about context windows.

Google (Gemini)
Prompting Strategies

Covers text generation, structured outputs, and model-specific guidance for Gemini.

Thinking Documentation

How Gemini’s reasoning works under the hood — thinking levels, thought summaries, and configuration.

OpenAI (GPT)
Prompt Engineering Guide

Covers identity, instructions, context management, and model-specific techniques.

Prompt Guidance (Model-Specific)

Per-model prompting guides with migration advice. Updated with each major model release.