before-you-build
Use this before implementing a product, feature, SaaS, AI app, or side project to score product risk and choose the smallest validation step.
Profile →npx skills add cosmicstack-labs/mercury-agent-skills --skill before-you-build --agent claude-code
Same command for any agent — swap --agent for codex, cursor, copilot.
Weekly change comes from our own snapshots, not the repository page — it measures attention, not adoption.
# Before You Build ## Purpose Use this skill before an agent starts building a product, feature, SaaS tool, AI app, side project, or startup idea. The goal is not to block shipping. The goal is to avoid spending engineering time on an idea whose biggest risk is still outside the codebase. Before implementation, produce: - A short risk verdict - A score across product risk dimensions - The riskiest assumption - The smallest validation step worth doing next - A clear build, test, or stop recommendation ## When To Use Use this skill when the user says they want to: - Build a new product or feature - Add an AI workflow to an existing product - Turn an idea into an MVP - Copy a competitor or trend - Ship a side project quickly - Start coding before talking to users - Ask whether an idea is worth building - Decide between multiple product bets Do not use this for: - Pure code debugging - Refactoring existing implementation - UI polish after the product bet is already validated - Legal, financial, medical, or security review - Choosing a tech stack ## Core Principle Most early product failures are not caused by missing code. They usually come from one or more of these gaps: - The buyer do
- Purpose
- When To Use
- Core Principle
- Inputs To Ask For
- Risk Dimensions
- 1. Demand Risk
- 2. Monetization Risk
- 3. Distribution Risk
- 4. Retention Risk
- 5. Trust Risk
- 6. Platform Risk
- 7. Feature Adoption Risk
- Scoring Rubric
- Evidence Quality
What does the before-you-build skill do?
Use this before implementing a product, feature, SaaS, AI app, or side project to score product risk and choose the smallest validation step.
How do I install it?
Run `npx skills add cosmicstack-labs/mercury-agent-skills --skill before-you-build --agent claude-code` — it drops the skill into your project so the agent can pick it up. Swap the --agent value for codex, cursor or copilot if you use one of those.
Where does this skill come from?
From cosmicstack-labs/mercury-agent-skills, a repository with 364 stars. We read it straight from the repository tree rather than a submitted listing, so what you see here is what is actually published.
Is a popular skill a good skill?
Not necessarily. Stars measure attention, not adoption — a repository can trend for a week and be abandoned. That is why we show the weekly change from our own snapshots next to the total, instead of a single flattering number.