# Idea Validation

> Guide founders through validating startup ideas before building. Use when a founder says "I have an idea", "help me validate", "is this a good idea", "should I build this", "customer discovery", or asks about product-market fit, market sizing, or customer interviews. Covers problem discovery, customer interviews, market validation, and go/no-go decisions.

- Skill: `samuelcastro/idea-validation` (Agent Skill, multi-file: 5 files)
- Install (CLI): `npx skillmds@latest add samuelcastro/idea-validation`
- Raw SKILL.md: https://api.skillmd.com/api/skills/samuelcastro/idea-validation/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Product & Planning
- Author: samuelcastro (https://skillmd.com/u/samuelcastro)
- Updated: 2026-09-22
- Page: https://skillmd.com/skills/samuelcastro/idea-validation

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# Idea Validation

Guide founders from raw idea to validated hypothesis with confidence to commit or kill.

## Workflow

### 1. Diagnose Stage

Ask: "Where are you in the journey?"

| Stage | Signals | Next Step |
|-------|---------|-----------|
| **Raw idea** | "I'm thinking about..." | → Go to Step 2 |
| **Hypothesis** | Has problem + solution defined | → Go to Step 3 |
| **Interviewed** | Talked to 5+ people | → Go to Step 4 |
| **Testing** | Has MVP/landing page | → Go to Step 5 |

### 2. Shape the Hypothesis

Help founder articulate three components (Kevin Hale/YC framework):

1. **Problem**: What burning pain exists? Who has it?
2. **Solution**: What's the experiment/MVP?
3. **Insight**: Why will YOU win? (unfair advantage)

Unfair advantages to probe for:
- Founder-market fit (lived the problem, domain expertise)
- Market timing (20%+ annual growth)
- 10x better product possibility
- Built-in distribution/word-of-mouth
- Network effects potential

Output: One-sentence hypothesis in format:
> "[Target customer] struggles with [problem] because [root cause]. We believe [solution] will work because [insight/unfair advantage]."

### 3. Validate the Problem

#### Quick Validation (60 min) — Tom Bilyeu Method

For rapid signal-checking before deep interviews:

**Problem Hunt (15 min)**
Search Reddit, Twitter, Facebook groups, forums for:
- "Why is there no..."
- "I wish someone would make..."
- "I've tried 5 different solutions..."
- "Paying $X but it doesn't even..."

Collect 10 specific complaints. Can't find 10? Different problem.

**Size Check (10 min)**
Google Trends + Keyword Planner:
- <1K monthly searches = Dead
- 1K-10K = Niche (can work)
- 10K-100K = Solid opportunity
- 100K+ = Major market

**Competition Map (15 min)**
Find top 5 competitors. Check pricing pages + 1-star reviews.
- Pricing <$50/mo + bad reviews = struggling market
- Pricing $100+ with good reviews = profitable space

Look for patterns: "too complicated", "missing X feature" = your opening.

#### Deep Validation — Customer Interviews

How many conversations?
- B2C with uniform behavior: ~20 interviews
- B2B with varied buying patterns: 50+ interviews
- Keep going until clear patterns emerge

See `references/interview-guide.md` for question scripts and signal detection.

**Critical rule**: Anything short of "I want this!" is really "No thanks."

### 4. Assess Market Pull

Look for these "lightbulb moments" from successful founders:

| Signal | Strength | Example |
|--------|----------|---------|
| Polite interest | ❌ Weak | "Sure, I'd check it out" |
| Unsolicited referrals | ✅ Strong | People you didn't talk to reach out |
| Interrupted pitch | ✅ Strong | "Wait, you can do WHAT?" |
| Pre-purchase on mockup | ✅ Strong | Signed customers from Figma prototype |
| Inbound after launch | ✅ Strong | 133 leads in 72 hours (Pinwheel) |

**The Mom Test**: Don't ask "Would you use this?" — ask "How have you tried to solve this before?" Past behavior > future predictions.

### 5. Test Before Building

Choose validation method based on idea type:

| Idea Type | Validation Method |
|-----------|-------------------|
| B2B SaaS | Sell on mockups/Figma before code |
| Consumer app | Simulate populated experience in Figma |
| Marketplace | Validate BOTH sides separately |
| Dev tools | Leverage personal network first, then SEO content |

**Nikita Bier principle**: Do things that don't scale. Make it the BEST it could ever be manually. If it works, then automate. If you only launch the "scalable" version, you won't know if it failed due to concept or execution.

**Landing page test** (if applicable):
- Create page: "Finally, [solution] for [specific audience]"
- Run $20-50 in ads
- Conversion benchmarks:
  - <1% = Kill immediately
  - 2-5% = Test further
  - 5%+ = Build immediately

### 6. Decision Checkpoint

#### GO Signals
- People reaching out unprompted
- Strong reactions in interviews ("I need this")
- Pre-sales or LOIs on mockups
- Clear pattern in 20+ conversations
- You have an unfair advantage

#### PIVOT Signals
- Adjacent problem keeps coming up
- Different customer segment more excited
- Core insight valid, solution wrong

#### KILL Signals
- Lukewarm reactions after 20+ interviews
- Have to "convince" people of the problem
- Can't find 10 complaints in 15 min searching
- No unfair advantage identified
- Market too small (<1K searches, <$1B TAM)

**Remember**: If you have to ask "Do I have product-market fit?" — you don't. When you have it, you know.

## Common Traps

See `references/traps.md` for the 7 deadly traps and how to avoid them.

## Reference Files

- `references/frameworks.md` — All 5 validation frameworks in detail
- `references/case-studies.md` — 8 founder stories (Vanta, Flexport, etc.)
- `references/interview-guide.md` — Question scripts + what to listen for
- `references/traps.md` — 7 traps with detection and avoidance

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*Adapted from [Linas Beliūnas's](https://linas.substack.com/p/onepersonunicorn) **The One-Person Unicorn** founder skill set.*