Skill

Pass

Audit score 90

product-lens

affaan-m/ecc

Validate product direction and diagnose the "why" before building—run founder-level reviews and pressure-test ideas.

What is product-lens?

Product Lens guides you through product diagnosis before implementation: validating the core thesis, auditing user journeys, prioritizing features, and reviewing projects for product-market fit signals. Use it when you need to pressure-test an idea, choose between features, or sanity-check direction before engineering planning starts.

Run structured product diagnostics with 7 hard questions (who, pain, why now, 10-star version, MVP, anti-goals, success metrics)
Review existing projects for product-market fit signals: usage growth, retention, revenue indicators, and competitive moat
Map actual user experience from install to first win, timing friction points and comparing to competitor onboarding
Prioritize features using ICE scoring (impact × confidence ÷ effort) with runway and team constraints
Generate actionable briefs and go/no-go recommendations, not essays

How to install product-lens

npx skills add null --skill product-lens

Claude Code

Cursor

Windsurf

Cline

How to use product-lens

1.Choose your mode: Product Diagnostic (validate a new idea), Founder Review (assess existing project), User Journey Audit (map onboarding friction), or Feature Prioritization (rank candidates)
2.For diagnostics: answer the 7 core questions (who, pain, why now, 10-star, MVP, anti-goals, metrics)
3.For founder review: provide README, CLAUDE.md, package.json, and recent commit history for analysis
4.For user journey audit: prepare to install/clone the product as a new user and document friction points
5.Review the output brief or scorecard, apply constraints (runway, team size, dependencies), and decide: build, pivot, or kill

Use cases

Good for

Before starting a feature: validate the "why" and core thesis with structured questions
Weekly product review: assess whether you're building the right thing and identify the one 10x opportunity
Choosing between competing features: score and rank candidates by impact, confidence, and effort
Pre-launch sanity check: audit the user journey from first install to first value
Converting a vague idea into a product brief before handing off to engineering planning

Who it's for

Founders and product managers validating ideas before committing resources
Engineering teams reviewing project direction and product-market fit signals
Teams stuck between multiple feature candidates and needing prioritization
Anyone running a weekly product review or pre-launch checkpoint

product-lens FAQ

When should I use this vs. product-capability?

Use Product Lens to validate the "why" and diagnose direction. Once you have a solid product brief and a go decision, hand off to product-capability to write an implementation-ready capability plan and SRS.

What if the diagnostic recommends "no, don't build this"?

That's the point. The skill surfaces risks and misalignments early, before you waste engineering time. Use the output to pivot, refocus, or kill the idea cleanly.

Can I use this for an existing product?

Yes. The Founder Review mode reads your current codebase and project signals to score product-market fit, identify the one 10x opportunity, and flag things you're building that don't matter.

How long does a product diagnostic take?

Typically 15–30 minutes to answer the 7 core questions thoroughly. User journey audits take longer (1–2 hours) because they involve actually using the product.

What metrics should I track for "how do you know it's working"?

Pick one primary metric tied to your thesis: daily active users, retention rate, feature adoption, revenue, or repeat-contributor rate. Avoid vanity metrics; focus on behavior that proves the core value.

Full instructions (SKILL.md)

Source of truth, from affaan-m/ecc.

name: product-lens description: Use this skill to validate the "why" before building, run product diagnostics, and pressure-test product direction before the request becomes an implementation contract. metadata: origin: ECC

Product Lens — Think Before You Build

This lane owns product diagnosis, not implementation-ready specification writing.

If the user needs a durable PRD-to-SRS or capability-contract artifact, hand off to product-capability.

When to Use

Before starting any feature — validate the "why"
Weekly product review — are we building the right thing?
When stuck choosing between features
Before a launch — sanity check the user journey
When converting a vague idea into a product brief before engineering planning starts

How It Works

Mode 1: Product Diagnostic

Like YC office hours but automated. Asks the hard questions:

1. Who is this for? (specific person, not "developers")
2. What's the pain? (quantify: how often, how bad, what do they do today?)
3. Why now? (what changed that makes this possible/necessary?)
4. What's the 10-star version? (if money/time were unlimited)
5. What's the MVP? (smallest thing that proves the thesis)
6. What's the anti-goal? (what are you explicitly NOT building?)
7. How do you know it's working? (metric, not vibes)

Output: a PRODUCT-BRIEF.md with answers, risks, and a go/no-go recommendation.

If the result is "yes, build this," the next lane is product-capability, not more founder-theater.

Mode 2: Founder Review

Reviews your current project through a founder lens:

1. Read README, CLAUDE.md, package.json, recent commits
2. Infer: what is this trying to be?
3. Score: product-market fit signals (0-10)
   - Usage growth trajectory
   - Retention indicators (repeat contributors, return users)
   - Revenue signals (pricing page, billing code, Stripe integration)
   - Competitive moat (what's hard to copy?)
4. Identify: the one thing that would 10x this
5. Flag: things you're building that don't matter

Mode 3: User Journey Audit

Maps the actual user experience:

1. Clone/install the product as a new user
2. Document every friction point (confusing steps, errors, missing docs)
3. Time each step
4. Compare to competitor onboarding
5. Score: time-to-value (how long until the user gets their first win?)
6. Recommend: top 3 fixes for onboarding

Mode 4: Feature Prioritization

When you have 10 ideas and need to pick 2:

1. List all candidate features
2. Score each on: impact (1-5) × confidence (1-5) ÷ effort (1-5)
3. Rank by ICE score
4. Apply constraints: runway, team size, dependencies
5. Output: prioritized roadmap with rationale

Output

All modes output actionable docs, not essays. Every recommendation has a specific next step.

Integration

Pair with:

/browser-qa to verify the user journey audit findings
/design-system audit for visual polish assessment
/canary-watch for post-launch monitoring
product-capability when the product brief needs to become an implementation-ready capability plan