Brainstorm Experiments Existing

This helps you design cheap experiments to validate product assumptions before building the full feature. It walks you through clarifying what you're testing, then suggests specific experiment types like fake door tests, prototypes with first-click testing, technical spikes, or A/B tests with proper risk mitigation. The output is structured around four key elements: the assumption you're testing, the exact experiment method, what metric you'll measure, and your success threshold. It's opinionated about measuring actual behavior rather than opinions, which is the right call. Useful when you have a feature idea but want to validate it won't be a waste of engineering time. Saves the experiment plan as markdown so you can share it with your team.

skills.sh installs: 2.9K
GitHub stars: 27.8K
last updated: Aug 21, 2026

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Install

$ npx -y skills add phuryn/pm-skills --skill brainstorm-experiments-existing --agent claude-code

Installs into .claude/skills of the current project.

Files

Design Experiments (Existing Product)

Design low-effort experiments to test product assumptions before committing to full implementation.

Context

You are helping a product team design experiments for $ARGUMENTS. The team has a feature idea and assumptions that need validation.

If the user provides files (PRDs, assumption lists, designs), read them first.

Instructions

The user will describe their idea and assumptions. Work through these steps:

Clarify the idea and assumptions: Confirm what the team wants to build and what they need to validate.
Suggest experiments for each assumption. Consider methods like:
- First-click testing or task completion with a prototype
- Feature stubs or fake door tests
- Technical spikes
- A/B tests on production (with risk mitigation)
- Wizard of Oz approaches
- Survey-based validation (behavioral, not opinion-based)