Free local tool

Experiment Protocol Builder

Build an exportable LLM experiment protocol and results-table template for testing Claude prompts, variants, fixtures, and success criteria.

how to test llm behaviorprompt experiment designClaude experiment protocol

Key facts

Cite facts
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Fact

Browser-only protocol

The builder runs entirely in the browser. The prompt variants and criteria you type are not uploaded.

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Fact

Evidence table included

The export includes fixture, variant, model, timestamp, score, notes, and raw-output fields.

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Fact

Controls before claims

The generated card asks you to lock model, source state, tools, fixtures, and scoring before reading outputs.

Interactive builder

Generate an experiment card

Controls to lock

Protocol output

Results table template

fixture_idvariantrunmodelscorenotesraw_output_ref

How to Use This Tool

  1. Define the behavior question. Write the narrow Claude behavior you want to test and choose the surface being tested.
  2. Add prompt variants and criteria. Paste two or more variants, set the number of runs per fixture, and define measurable success criteria.
  3. Export the protocol. Copy or download the generated Markdown protocol and results table before running the experiment.

Tool FAQ

Does the builder run Claude?

No. It creates the protocol and results table. You run the experiment in your chosen Claude surface and paste raw evidence into your own records.

Can I use it for non-Claude LLMs?

Yes. The tool is written for Curious Claude readers, but the protocol fields work for any LLM if you record the model, surface, and source state.

What should I do before publishing a result?

Preserve the exact prompt, fixtures, model ID, date, source state, scoring rule, raw output, and scorer notes. Without those fields, publish it as a protocol note, not a result.

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