Validate ideas
before you build them.

Product Kit is a free, open-source toolkit that brings structured product thinking to Claude. 10 guided conversations. 7 artifacts. 1 spec.

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Building is easy. Building the right thing is hard.

Claude Code. Codex. Cursor. Windsurf. You can go from idea to working app in hours. But easier to build doesn't mean smarter to build.

Most people skip straight to code. No user research. No problem validation. No spec. The result?

Polished solutions for problems that don't exist.

Before you ask "Can we build it?" — ask "Should we build it?"

What if the same AI tool you use to build could first help you validate the idea?

How It Works

Product Kit guides you through 7 steps. Each step reads the previous one. Nothing gets skipped.

1Constitution
→
2Users
→
3Problem
→
4Assumptions
→
5Solution
→
6Prioritize
→
7Spec

Plus three utility commands — Clarify, Analyze, and Bootstrap — that you can run anytime.

Setup

Product Kit works two ways. Pick the one that fits your style.

No terminal required

Use Product Kit directly in Claude with the Cowork plugin.

  1. Download product-kit-plugin.zip
  2. In Claude, go to Plugins → + → Upload plugin
  3. Select the zip file
  4. Done — type /product-kit:users to start

For terminal users

Requires Node.js 18+ and Claude Code.

npm install -g productkit
productkit init my-project
cd my-project
claude

Then run the slash commands in order: /productkit.constitution, /productkit.users, etc.

Options: Use --existing to add to a current project, --minimal to skip constitution, or --artifact-dir docs/product to store artifacts in a custom directory.

CLI tools: productkit status, productkit export, productkit diff, productkit doctor — manage and inspect your artifacts from the terminal.

The 7 Steps

Each step is a guided conversation. Claude asks the questions, pushes back on vague answers, and writes a markdown artifact when done.

1

Constitution

"Make the hard tradeoffs before you write a line of code." 
/productkit.constitution

What Claude asks you

  • What does your product stand for?
  • What will you never do?
  • What principles guide decisions?

What it produces — constitution.md

  • Vision
  • Core Principles
  • Non-Negotiables
  • Decision Framework
2

Users

"Everyone" is not a user. 
/productkit.users

What Claude asks you

  • Who specifically has this problem?
  • What's their day-to-day like?
  • How do they solve it today?

What it produces — users.md

  • Primary persona (specific, detailed)
  • Secondary persona
  • Key insight
3

Problem

"We need an app" → "What problem does that app solve?" 
/productkit.problem

What Claude asks you

  • What specific pain are users feeling?
  • How often does it happen?
  • What's the root cause?

What it produces — problem.md

  • Problem statement grounded in evidence
  • Impact (frequency + severity)
  • Root cause
  • Scope (in + out)
4

Assumptions

What are you betting on without knowing it? 
/productkit.assumptions

What Claude does

  • Reads your artifacts so far
  • Surfaces hidden risks
  • Identifies what you're taking for granted

What it produces — assumptions.md

  • Critical assumptions (low confidence, high impact)
  • Validation plan for top risks
  • Recommended next steps
5

Solution

NOW you can brainstorm what to build. 
/productkit.solution

What Claude asks you

  • What approaches have you considered?
  • How does each trace to a user need?
  • What are the tradeoffs?

What it produces — solution.md

  • Options considered (with pros/cons)
  • Recommended solution for v1
  • What's deferred to v2+
  • Key risks
6

Prioritize

"What's the smallest thing you can ship that solves the core problem?" 
/productkit.prioritize

What Claude does

  • Scores features: Impact x Confidence / Effort
  • Draws the v1 line
  • Justifies every cut

What it produces — priorities.md

  • Ranked feature table with scores
  • Must-haves vs nice-to-haves
  • What's deferred and why
7

Spec

Everything synthesized. Every claim traced. Ready to build. 
/productkit.spec

What Claude does

  • Reads all 6 previous artifacts
  • Synthesizes into one document
  • Links every claim to its source

What it produces — spec.md

  • Overview, principles, users, problem
  • Solution with acceptance criteria
  • Risks, open questions, success metrics

Utility Commands

Run these at any stage to check your work.

Clarify

/productkit.clarify

Find contradictions across your artifacts. Run this anytime something feels off. Claude reads everything you've written and flags inconsistencies.

Analyze

/productkit.analyze

Get a score out of 10. Strengths. Gaps. Contradictions. Verdict: "Ready to build, or needs more work?"

Bootstrap

/productkit.bootstrap

Already have a codebase? Bootstrap scans your project and auto-drafts all missing artifacts in one session. Great for existing projects.

What You End Up With

After running all 7 steps, your project contains:

my-project/
├── constitution.md   # Product principles
├── users.md          # User personas
├── problem.md        # Problem statement
├── assumptions.md   # Prioritized assumptions
├── solution.md       # Chosen solution
├── priorities.md     # Ranked feature list
└── spec.md           # Complete product spec

Use --artifact-dir during init to store artifacts in a subdirectory (e.g. docs/product/) instead of the project root.

7 artifacts. 1 validated product idea. Hand spec.md to Claude Code and build the right thing.

Ready to validate your idea?

Free. Open source. MIT license.

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