---
name: throwaway-prototype-brief
description: "Scopes a disposable prototype that answers one design question, naming what to measure and what to delete when the answer is in. Use when a design or technical question needs a quick disposable prototype with a clear measure and a delete plan. Do not use for building the real feature or writing production-quality code. Related topics: coding, product."
---

# Throwaway Prototype Brief

Scopes a disposable prototype that answers one design question, naming what to measure and what to delete when the answer is in.

## When to use

Use this skill when a design or technical question needs a quick disposable prototype with a clear measure and a delete plan. Do not use it for building the real feature or writing production-quality code.

## Workflow

1. Ask the user for each input listed below in a single message, skipping any they have already given. Where options are listed, offer them, but accept other answers too.
2. Reduce the design question to one answerable question, splitting off and parking the rest.
3. State what the prototype will deliberately skip and what it must include to answer the question.
4. Define the measurements, their method and the result that would decide between options.
5. Plan build steps that reach the first measurement early and set a kill rule at the time box.
6. Write the findings format and the delete list, including branches and credentials.

## Inputs

- **Design question** (longer free text)
- **Options being compared** (longer free text)
- **Time box** (choose one: Half a day, One day, Three days)
- **Stack for the prototype** (free text, e.g. "Language and tools")
- **Success signal** (free text, e.g. "What result would settle the question")

## Output

A one-page brief with question, scope in and out, measurements, steps, kill rule, findings format and a delete checklist.

## Prompt template

Fill the inputs into this template and follow it as the full instruction.

### Throwaway Prototype Brief

Scope a prototype that is built only to be thrown away.

- Design question: {{Design question}}
- Options being compared: {{Options being compared}}
- Time box: {{Time box}}
- Stack for the prototype: {{Stack for the prototype}}
- Success signal: {{Success signal}}

Check first that the question is a single, answerable one; if it is several, split them and pick the one that blocks the most. Define what the prototype needs and what it should skip on purpose, such as tests, error handling, styling and security. List exactly what to measure, with the method and the number or observation that would decide each option. Plan the build in steps that reach the first measurement as early as possible. State a kill rule: when the time box ends, stop and report even without a clean answer. Write down the findings format, then the delete list: every branch, file, service and credential to remove afterwards, with a note that no prototype code is copied into the real project.

## Pitfalls

- Letting the prototype grow into the product, so shortcuts become permanent.
- Measuring nothing specific, which leaves the team arguing from impressions.
- Forgetting to delete the temporary services and credentials.