feat: add startup-business-analyst plugin

Comprehensive startup analysis plugin with market sizing, financial modeling, team planning, and strategic research for early-stage companies.

- 5 skills: market sizing, financial modeling, team planning, competitive analysis, metrics
- 3 commands: market-opportunity, financial-projections, business-case
- 1 agent: startup-analyst
- Covers TAM/SAM/SOM, unit economics, competitive landscape, hiring plans

plugins/startup-business-analyst/commands/business-case.md

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+---
+name: business-case
+description: Generate comprehensive investor-ready business case document with market, solution, financials, and strategy
+allowed-tools: [Read, Write, Grep, Glob, WebSearch, WebFetch, Bash]
+---
+
+Generate a comprehensive, investor-ready business case document covering market opportunity, solution, competitive landscape, financial projections, team, risks, and funding ask for startup fundraising and strategic planning.
+
+## What This Command Does
+
+Create a complete business case including:
+1. Executive summary
+2. Problem and market opportunity
+3. Solution and product
+4. Competitive analysis and differentiation
+5. Financial projections
+6. Go-to-market strategy
+7. Team and organization
+8. Risks and mitigation
+9. Funding ask and use of proceeds
+
+## Instructions for Claude
+
+When this command is invoked, follow these steps:
+
+### Step 1: Gather Context
+
+Ask the user for key information:
+
+**Company Basics:**
+- Company name and elevator pitch
+- Stage (pre-seed, seed, Series A)
+- Problem being solved
+- Target customers
+
+**Audience:**
+- Who will read this? (VCs, angels, strategic partners)
+- What's the primary goal? (fundraising, partnership, internal planning)
+
+**Available Materials:**
+- Existing pitch deck or docs?
+- Market sizing data?
+- Financial model?
+- Competitive analysis?
+
+### Step 2: Activate Relevant Skills
+
+Reference skills for comprehensive analysis:
+- **market-sizing-analysis** - TAM/SAM/SOM calculations
+- **startup-financial-modeling** - Financial projections
+- **competitive-landscape** - Competitive analysis frameworks
+- **team-composition-analysis** - Organization planning
+- **startup-metrics-framework** - Key metrics and benchmarks
+
+### Step 3: Structure the Business Case
+
+Create a comprehensive document with these sections:
+
+---
+
+## Business Case Document Structure
+
+### Section 1: Executive Summary (1-2 pages)
+
+**Company Overview:**
+- One-sentence description
+- Founded, location, stage
+- Team highlights
+
+**Problem Statement:**
+- Core problem being solved (2-3 sentences)
+- Market pain quantified
+
+**Solution:**
+- How the product solves it (2-3 sentences)
+- Key differentiation
+
+**Market Opportunity:**
+- TAM: $X.XB
+- SAM: $X.XM
+- SOM (Year 5): $X.XM
+
+**Traction:**
+- Current metrics (MRR, customers, growth rate)
+- Key milestones achieved
+
+**Financial Snapshot:**
+```
+| Metric | Current | Year 1 | Year 2 | Year 3 |
+|--------|---------|--------|--------|--------|
+| ARR | $X | $Y | $Z | $W |
+| Customers | X | Y | Z | W |
+| Team Size | X | Y | Z | W |
+```
+
+**Funding Ask:**
+- Amount seeking
+- Use of proceeds (top 3-4)
+- Expected milestones
+
+### Section 2: Problem & Market Opportunity (2-3 pages)
+
+**The Problem:**
+- Detailed problem description
+- Who experiences this problem
+- Current solutions and their limitations
+- Cost of the problem (quantified)
+
+**Market Landscape:**
+- Industry overview
+- Key trends driving opportunity
+- Market growth rate and drivers
+
+**Market Sizing:**
+- TAM calculation and methodology
+- SAM with filters applied
+- SOM with assumptions
+- Validation and data sources
+- Comparison to public companies
+
+**Target Customer Profile:**
+- Primary segments
+- Customer characteristics
+- Decision-makers and buying process
+
+### Section 3: Solution & Product (2-3 pages)
+
+**Product Overview:**
+- What it does (features and capabilities)
+- How it works (architecture/approach)
+- Key differentiators
+- Technology advantages
+
+**Value Proposition:**
+- Benefits by customer segment
+- ROI or value delivered
+- Time to value
+
+**Product Roadmap:**
+- Current state
+- Near-term (6 months)
+- Medium-term (12-18 months)
+- Vision (2-3 years)
+
+**Intellectual Property:**
+- Patents (filed, pending)
+- Proprietary technology
+- Data advantages
+- Defensibility
+
+### Section 4: Competitive Analysis (2 pages)
+
+**Competitive Landscape:**
+- Direct competitors
+- Indirect competitors (alternatives)
+- Adjacent players (potential entrants)
+
+**Competitive Matrix:**
+```
+| Feature/Factor | Us | Comp A | Comp B | Comp C |
+|----------------|----|---------| -------|--------|
+| Feature 1 | ✓ | ✓ | ✗ | ✓ |
+| Feature 2 | ✓ | ✗ | ✓ | ✗ |
+| Pricing | $X | $Y | $Z | $W |
+```
+
+**Differentiation:**
+- 3-5 key differentiators
+- Why these matter to customers
+- Defensibility of advantages
+
+**Competitive Positioning:**
+- Positioning map (2-3 dimensions)
+- Market positioning statement
+
+**Barriers to Entry:**
+- What protects against competition
+- Network effects, switching costs, etc.
+
+### Section 5: Business Model & Go-to-Market (2 pages)
+
+**Business Model:**
+- Revenue model (subscriptions, transactions, etc.)
+- Pricing strategy and tiers
+- Customer acquisition approach
+- Expansion revenue strategy
+
+**Go-to-Market Strategy:**
+- Customer acquisition channels
+- Sales model (self-serve, sales-led, hybrid)
+- Customer acquisition cost (CAC)
+- Sales cycle and conversion rates
+
+**Marketing Strategy:**
+- Positioning and messaging
+- Channel strategy
+- Content and demand generation
+- Partnerships and integrations
+
+**Customer Success:**
+- Onboarding approach
+- Support model
+- Retention strategy
+- Net dollar retention target
+
+### Section 6: Financial Projections (2-3 pages)
+
+**Revenue Model:**
+- Cohort-based projections
+- Key assumptions
+- Revenue breakdown by segment
+
+**3-Year Financial Summary:**
+```
+| Metric | Year 1 | Year 2 | Year 3 |
+|--------|--------|--------|--------|
+| Revenue | $X.XM | $Y.YM | $Z.ZM |
+| Gross Margin | XX% | XX% | XX% |
+| Operating Expenses | $X.XM | $Y.YM | $Z.ZM |
+| Net Income | ($X.XM) | ($Y.YM) | $Z.ZM |
+| EBITDA Margin | (XX%) | (XX%) | XX% |
+```
+
+**Unit Economics:**
+- CAC: $X,XXX
+- LTV: $X,XXX
+- LTV:CAC ratio: X.X
+- CAC Payback: XX months
+- Gross margin: XX%
+
+**Key Metrics Trajectory:**
+```
+| Metric | Current | Year 1 | Year 2 | Year 3 |
+|--------|---------|--------|--------|--------|
+| MRR/ARR | $X | $Y | $Z | $W |
+| Customers | X | Y | Z | W |
+| Net Dollar Retention | XX% | XX% | XX% | XX% |
+| Burn Multiple | X.X | X.X | X.X | X.X |
+```
+
+**Scenario Analysis:**
+- Conservative, base, optimistic
+- Key drivers and sensitivities
+
+**Path to Profitability:**
+- Break-even timeline
+- Key milestones
+- Unit economics at scale
+
+### Section 7: Team & Organization (1-2 pages)
+
+**Leadership Team:**
+For each founder/executive:
+- Name, title, photo (if available)
+- Relevant background (2-3 sentences)
+- Key accomplishments
+- Why they're uniquely qualified
+
+**Current Team:**
+- Headcount by department
+- Key hires and their backgrounds
+- Advisory board
+
+**Hiring Plan:**
+- Year 1-3 headcount growth
+- Key roles to fill
+- Recruiting strategy
+
+**Organization Evolution:**
+```
+Current (5 people) → Year 1 (15) → Year 2 (35) → Year 3 (60)
+Engineering: 3 → 7 → 15 → 25
+Sales & Marketing: 1 → 4 → 12 → 20
+Other: 1 → 4 → 8 → 15
+```
+
+**Equity & Compensation:**
+- Option pool sizing
+- Compensation philosophy
+- Retention strategy
+
+### Section 8: Traction & Milestones (1 page)
+
+**Current Traction:**
+- Revenue or user metrics
+- Growth rate
+- Key customer wins
+- Product development progress
+
+**Milestones Achieved:**
+- Product launches
+- Funding rounds
+- Team hires
+- Customer acquisition
+- Partnerships
+
+**Upcoming Milestones (12-18 months):**
+- Product milestones
+- Revenue targets
+- Customer goals
+- Team goals
+- Partnership goals
+
+### Section 9: Risks & Mitigation (1 page)
+
+**Market Risks:**
+- Market size assumptions
+- Competitive intensity
+- Substitute adoption
+- Mitigation strategies
+
+**Execution Risks:**
+- Product development
+- Go-to-market effectiveness
+- Hiring and retention
+- Mitigation strategies
+
+**Financial Risks:**
+- Burn rate management
+- Fundraising market
+- Unit economics
+- Mitigation strategies
+
+**Regulatory/External Risks:**
+- Compliance requirements
+- Data privacy
+- Economic conditions
+- Mitigation strategies
+
+### Section 10: Funding Request & Use of Proceeds (1 page)
+
+**Funding Ask:**
+- Amount seeking: $X.XM
+- Structure: Equity, SAFE, convertible note
+- Target valuation: $X.XM (if applicable)
+
+**Use of Proceeds:**
+```
+Total Raise: $5.0M
+- Product Development: $2.0M (40%)
+  • Engineering team expansion
+  • Infrastructure and tools
+  • Product roadmap execution
+
+- Sales & Marketing: $2.0M (40%)
+  • Sales team hiring (5 AEs)
+  • Marketing programs
+  • Demand generation
+
+- Operations & G&A: $0.5M (10%)
+  • Finance/legal/HR
+  • Office and facilities
+
+- Working Capital: $0.5M (10%)
+  • 6-month buffer
+```
+
+**Milestones to Achieve:**
+- Revenue: $X.XM ARR (X% growth)
+- Customer: XXX customers
+- Product: Key features launched
+- Team: XX employees
+- Metric: Key metric targets
+
+**Expected Timeline:**
+- 18-24 month runway
+- Achieve milestones in 15-18 months
+- 6-month buffer for next raise
+
+**Next Round:**
+- Series A in 18-24 months
+- Expected metrics at that time
+- Target raise amount
+
+---
+
+### Step 4: Enhance with Visuals
+
+Suggest including:
+- Charts for market sizing (TAM funnel)
+- Product screenshots or mockups
+- Positioning maps
+- Financial trend charts (revenue, customers, burn)
+- Organization chart
+- Timeline/roadmap
+- Use of proceeds pie chart
+
+### Step 5: Provide Additional Sections (Optional)
+
+**If Relevant, Add:**
+- Regulatory/Compliance section (for regulated industries)
+- Technology Architecture (for deep tech)
+- Clinical/Scientific Data (for biotech/health tech)
+- Unit Economics Deep Dive (for complex business models)
+- Strategic Partnerships (if material to strategy)
+
+### Step 6: Create Executive Summary Slide
+
+Provide one-page summary for quick review:
+- Problem & Solution (3 bullets each)
+- Market: TAM/SAM/SOM
+- Traction: Key metrics
+- Team: Founders
+- Ask: Amount and use
+- Contact information
+
+### Step 7: Save Business Case
+
+Offer to save as markdown:
+- Filename: `business-case-[company-name]-YYYY-MM-DD.md`
+- Suggest converting to PDF for sharing
+- Provide tips for presentation format
+
+## Best Practices
+
+**Do:**
+- Lead with customer problem
+- Quantify everything
+- Show, don't just tell (use data)
+- Be realistic on projections
+- Acknowledge risks honestly
+- Cite all data sources
+- Keep executive summary concise
+- Focus on differentiation
+
+**Don't:**
+- Use jargon without explanation
+- Make unsupported claims
+- Ignore competition
+- Be overly optimistic
+- Skip the "why now"
+- Forget to proofread
+- Use generic templates without customization
+
+## Integration with Other Commands
+
+This command synthesizes outputs from:
+- `/market-opportunity` - Include TAM/SAM/SOM analysis
+- `/financial-projections` - Include full financial model
+
+## Example Usage
+
+```
+User: /business-case
+
+Claude: I'll create a comprehensive business case document. Let me gather the key information first.
+
+Company name and description?
+→ "AcmeCorp - AI-powered email marketing for e-commerce"
+
+Who is the audience?
+→ "Series A investors"
+
+What materials do you have?
+→ "We have market sizing and financial model done"
+
+[Claude creates comprehensive 15-20 page business case with all sections]
+```
+
+## Notes
+
+- Business case creation takes 1-2 hours
+- Result is investor-grade document
+- Can be used for pitch deck development
+- Update quarterly or for funding rounds
+- Customize sections based on audience
+- Keep executive summary to 2 pages max

plugins/startup-business-analyst/commands/financial-projections.md

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+---
+name: financial-projections
+description: Create detailed 3-5 year financial model with revenue, costs, cash flow, and scenarios
+allowed-tools: [Read, Write, Grep, Glob, Bash]
+---
+
+Create a comprehensive 3-5 year financial model with revenue projections, cost structure, headcount planning, cash flow analysis, and three-scenario modeling (conservative, base, optimistic) for startup financial planning and fundraising.
+
+## What This Command Does
+
+This command builds a complete financial model including:
+1. Cohort-based revenue projections
+2. Detailed cost structure (COGS, S&M, R&D, G&A)
+3. Headcount planning by role
+4. Monthly cash flow analysis
+5. Key metrics (CAC, LTV, burn rate, runway)
+6. Three-scenario analysis
+
+## Instructions for Claude
+
+When this command is invoked, follow these steps:
+
+### Step 1: Gather Model Inputs
+
+Ask the user for essential information:
+
+**Business Model:**
+- Revenue model (SaaS, marketplace, transaction, etc.)
+- Pricing structure (tiers, average price)
+- Target customer segments
+
+**Starting Point:**
+- Current MRR/ARR (if any)
+- Current customer count
+- Current team size
+- Current cash balance
+
+**Growth Assumptions:**
+- Expected monthly customer acquisition
+- Customer retention/churn rate
+- Average contract value (ACV)
+- Sales cycle length
+
+**Cost Assumptions:**
+- Gross margin or COGS %
+- S&M budget or CAC target
+- Current burn rate (if applicable)
+
+**Funding:**
+- Planned fundraising (amount, timing)
+- Pre/post-money valuation
+
+### Step 2: Activate startup-financial-modeling Skill
+
+The startup-financial-modeling skill provides frameworks. Reference it for:
+- Revenue modeling approaches
+- Cost structure templates
+- Headcount planning guidance
+- Scenario analysis methods
+
+### Step 3: Build Revenue Model
+
+**Use Cohort-Based Approach:**
+
+For each month, track:
+1. New customers acquired
+2. Existing customers retained (apply churn)
+3. Revenue per cohort (customers × ARPU)
+4. Expansion revenue (upsells)
+
+**Formula:**
+```
+MRR (Month N) = Σ across all cohorts:
+  (Cohort Size × Retention Rate × ARPU) + Expansion
+```
+
+**Project:**
+- Monthly detail for Year 1-2
+- Quarterly detail for Year 3
+- Annual for Years 4-5
+
+### Step 4: Model Cost Structure
+
+Break down operating expenses:
+
+**1. Cost of Goods Sold (COGS)**
+- Hosting/infrastructure (% of revenue or fixed)
+- Payment processing (% of revenue)
+- Variable customer support
+- Third-party services
+
+Target gross margin:
+- SaaS: 75-85%
+- Marketplace: 60-70%
+- E-commerce: 40-60%
+
+**2. Sales & Marketing (S&M)**
+- Sales team compensation
+- Marketing programs
+- Tools and software
+- Target: 40-60% of revenue (early stage)
+
+**3. Research & Development (R&D)**
+- Engineering team
+- Product management
+- Design
+- Target: 30-40% of revenue
+
+**4. General & Administrative (G&A)**
+- Executive team
+- Finance, legal, HR
+- Office and facilities
+- Target: 15-25% of revenue
+
+### Step 5: Plan Headcount
+
+Create role-by-role hiring plan:
+
+**Reference team-composition-analysis skill for:**
+- Roles by stage
+- Compensation benchmarks
+- Hiring velocity assumptions
+
+**For each role:**
+- Title and department
+- Start date (month/quarter)
+- Base salary
+- Fully-loaded cost (salary × 1.3-1.4)
+- Equity grant
+
+**Track departmental ratios:**
+- Engineering: 40-50% of team
+- Sales & Marketing: 25-35%
+- G&A: 10-15%
+- Product/CS: 10-15%
+
+### Step 6: Calculate Cash Flow
+
+Monthly cash flow projection:
+
+```
+Beginning Cash Balance
++ Cash Collected (revenue, consider payment terms)
+- Operating Expenses
+- CapEx
+= Ending Cash Balance
+
+Monthly Burn = Revenue - Expenses (if negative)
+Runway = Cash Balance / Monthly Burn Rate
+```
+
+**Include Funding Events:**
+- Timing of raises
+- Amount raised
+- Use of proceeds
+- Impact on cash balance
+
+### Step 7: Compute Key Metrics
+
+Calculate monthly/quarterly:
+
+**Unit Economics:**
+- CAC (S&M spend / new customers)
+- LTV (ARPU × margin% / churn rate)
+- LTV:CAC ratio (target > 3.0)
+- CAC payback period (target < 18 months)
+
+**Efficiency Metrics:**
+- Burn multiple (net burn / net new ARR) - target < 2.0
+- Magic number (net new ARR / S&M spend) - target > 0.5
+- Rule of 40 (growth% + margin%) - target > 40%
+
+**Cash Metrics:**
+- Monthly burn rate
+- Runway in months
+- Cash efficiency
+
+### Step 8: Create Three Scenarios
+
+Build conservative, base, and optimistic projections:
+
+**Conservative (P10):**
+- New customers: -30% vs. base
+- Churn: +20% vs. base
+- Pricing: -15% vs. base
+- CAC: +25% vs. base
+
+**Base (P50):**
+- Most likely assumptions
+- Primary planning scenario
+
+**Optimistic (P90):**
+- New customers: +30% vs. base
+- Churn: -20% vs. base
+- Pricing: +15% vs. base
+- CAC: -25% vs. base
+
+### Step 9: Generate Financial Model Report
+
+Create comprehensive markdown report with tables:
+
+**Section 1: Executive Summary**
+- 3-5 year financial snapshot
+- Key metrics at scale
+- Funding requirements
+
+**Section 2: Model Assumptions**
+- Revenue model and pricing
+- Growth assumptions
+- Cost structure assumptions
+- Headcount plan summary
+
+**Section 3: Revenue Projections**
+Monthly/quarterly tables showing:
+```
+| Month | New Customers | Total Customers | MRR | ARR | Growth % |
+|-------|---------------|-----------------|-----|-----|----------|
+```
+
+**Section 4: Cost Breakdown**
+```
+| Department | Year 1 | Year 2 | Year 3 | % Revenue |
+|------------|--------|--------|--------|-----------|
+| COGS       | $X     | $Y     | $Z     | XX%       |
+| S&M        | $X     | $Y     | $Z     | XX%       |
+| R&D        | $X     | $Y     | $Z     | XX%       |
+| G&A        | $X     | $Y     | $Z     | XX%       |
+```
+
+**Section 5: Headcount Plan**
+```
+| Department | Current | Year 1 | Year 2 | Year 3 |
+|------------|---------|--------|--------|--------|
+| Engineering| X       | Y      | Z      | W      |
+```
+
+**Section 6: Cash Flow Analysis**
+```
+| Quarter | Revenue | Expenses | Net Burn | Cash Balance | Runway |
+|---------|---------|----------|----------|--------------|--------|
+```
+
+**Section 7: Key Metrics**
+```
+| Metric | Year 1 | Year 2 | Year 3 | Target |
+|--------|--------|--------|--------|--------|
+| CAC | $X | $Y | $Z | <$A |
+| LTV | $X | $Y | $Z | >$B |
+| Burn Multiple | X | Y | Z | <2.0 |
+```
+
+**Section 8: Scenario Analysis**
+```
+| Scenario | Year 3 ARR | Customers | Burn | Runway |
+|----------|------------|-----------|------|--------|
+| Conservative | $Xم | Y | $Z | W mo |
+| Base | $X | Y | $Z | W mo |
+| Optimistic | $X | Y | $Z | W mo |
+```
+
+**Section 9: Funding Requirements**
+- Amount needed
+- Use of proceeds breakdown
+- Milestones to achieve
+- Expected valuation impact
+
+**Section 10: Validation**
+- Sanity checks performed
+- Benchmark comparisons
+- Risk factors
+- Assumptions to monitor
+
+### Step 10: Save Model
+
+Offer to save as markdown file:
+- Suggest filename: `financial-projections-YYYY-MM-DD.md`
+- Include note that user can convert to Excel/Sheets
+- Provide formulas for key calculations
+
+## Financial Model Best Practices
+
+**Do:**
+- Use cohort-based revenue model
+- Include 3 scenarios
+- Show monthly detail (Year 1-2)
+- Calculate key metrics
+- Validate against benchmarks
+- Document all assumptions
+- Show cash flow and runway
+- Include fundraising milestones
+
+**Don't:**
+- Be overly optimistic on growth
+- Underestimate costs
+- Forget fully-loaded compensation
+- Ignore cash timing
+- Skip scenario analysis
+- Use static headcount
+- Forget to validate
+
+## Integration with Other Commands
+
+Pairs well with:
+- `/market-opportunity` - Use SOM for revenue ceiling
+- `/business-case` - Include projections in business case
+
+## Example Usage
+
+```
+User: /financial-projections
+
+Claude: I'll create a comprehensive financial model for your startup. Let me gather the key inputs.
+
+What's your business model?
+→ "B2B SaaS, subscription-based"
+
+Current state?
+→ "$50K MRR, 100 customers, 5-person team, $500K cash"
+
+Growth assumptions?
+→ "Expect 15% MoM growth, 10% monthly churn, $500 ACV"
+
+[Claude builds complete model with all sections]
+```
+
+## Notes
+
+- Model building takes 45-90 minutes
+- Results in comprehensive planning tool
+- Update monthly to track vs. actuals
+- Share with investors and board
+- Use for fundraising decks
+- Basis for budget and hiring decisions

plugins/startup-business-analyst/commands/market-opportunity.md

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+---
+name: market-opportunity
+description: Generate comprehensive market opportunity analysis with TAM/SAM/SOM calculations
+allowed-tools: [Read, Write, Grep, Glob, WebSearch, WebFetch, Bash]
+---
+
+Generate a comprehensive market opportunity analysis for a startup, including Total Addressable Market (TAM), Serviceable Available Market (SAM), and Serviceable Obtainable Market (SOM) calculations using both bottom-up and top-down methodologies.
+
+## What This Command Does
+
+This command guides through an interactive market sizing process to:
+1. Define the target market and customer segments
+2. Gather relevant market data
+3. Calculate TAM using bottom-up methodology
+4. Validate with top-down analysis
+5. Narrow to SAM with appropriate filters
+6. Estimate realistic SOM (3-5 year opportunity)
+7. Present findings in a formatted report
+
+## Instructions for Claude
+
+When this command is invoked, follow these steps:
+
+### Step 1: Gather Context
+
+Ask the user for essential information:
+- **Product/Service Description:** What problem is being solved?
+- **Target Customers:** Who is the ideal customer? (industry, size, geography)
+- **Business Model:** How does pricing work? (subscription, transaction, etc.)
+- **Stage:** What stage is the company? (pre-launch, seed, Series A)
+- **Geography:** Initial target market (US, North America, Global)
+
+### Step 2: Activate market-sizing-analysis Skill
+
+The market-sizing-analysis skill provides comprehensive methodologies. Reference it for:
+- Bottom-up calculation frameworks
+- Top-down validation approaches
+- Industry-specific templates
+- Data source recommendations
+
+### Step 3: Conduct Bottom-Up Analysis
+
+**For B2B/SaaS:**
+1. Define customer segments (company size, industry, use case)
+2. Estimate number of companies in each segment
+3. Determine average contract value (ACV) per segment
+4. Calculate TAM: Σ (Segment Size × ACV)
+
+**For Consumer/Marketplace:**
+1. Define target user demographics
+2. Estimate total addressable users
+3. Determine average revenue per user (ARPU)
+4. Calculate TAM: Total Users × ARPU × Frequency
+
+**For Transactions/E-commerce:**
+1. Estimate total transaction volume (GMV)
+2. Determine take rate or margin
+3. Calculate TAM: Total GMV × Take Rate
+
+### Step 4: Gather Market Data
+
+Use available tools to research:
+- **WebSearch:** Find industry reports, market size estimates, public company data
+- **Cite all sources** with URLs and publication dates
+- **Document assumptions** clearly
+
+Recommended data sources (from skill):
+- Government data (Census, BLS)
+- Industry reports (Gartner, Forrester, Statista)
+- Public company filings (10-K reports)
+- Trade associations
+- Academic research
+
+### Step 5: Top-Down Validation
+
+Validate bottom-up calculation:
+1. Find total market category size from research
+2. Apply geographic filters
+3. Apply segment/product filters
+4. Compare to bottom-up TAM (should be within 30%)
+
+If variance > 30%, investigate and explain differences.
+
+### Step 6: Calculate SAM
+
+Apply realistic filters to narrow TAM:
+- **Geographic:** Regions actually serviceable
+- **Product Capability:** Features needed to serve
+- **Market Readiness:** Customers ready to adopt
+- **Addressable Switching:** Can reach and convert
+
+Formula:
+```
+SAM = TAM × Geographic % × Product Fit % × Market Readiness %
+```
+
+### Step 7: Estimate SOM
+
+Calculate realistic obtainable market share:
+
+**Conservative Approach (Recommended):**
+- Year 3: 2-3% of SAM
+- Year 5: 4-6% of SAM
+
+**Consider:**
+- Competitive intensity
+- Available resources (funding, team)
+- Go-to-market effectiveness
+- Differentiation strength
+
+### Step 8: Create Market Sizing Report
+
+Generate a comprehensive markdown report with:
+
+**Section 1: Executive Summary**
+- Market opportunity in one paragraph
+- TAM/SAM/SOM headline numbers
+
+**Section 2: Market Definition**
+- Problem being solved
+- Target customer profile
+- Geographic scope
+- Time horizon
+
+**Section 3: Bottom-Up Analysis**
+- Customer segment breakdown
+- Segment sizing with sources
+- TAM calculation with formula
+- Assumptions documented
+
+**Section 4: Top-Down Validation**
+- Industry category and size
+- Filter application
+- Validated TAM
+- Comparison to bottom-up
+
+**Section 5: SAM Calculation**
+- Filters applied with rationale
+- SAM formula and result
+- Segment-level breakdown
+
+**Section 6: SOM Projection**
+- Market share assumptions
+- Year 3 and Year 5 estimates
+- Customer count implications
+- Revenue projections
+
+**Section 7: Market Growth**
+- Industry growth rate (CAGR)
+- Key growth drivers
+- 5-year market evolution
+
+**Section 8: Validation and Sanity Checks**
+- Public company comparisons
+- Customer count validation
+- Competitive context
+
+**Section 9: Investment Thesis**
+- Market opportunity assessment
+- Key positives and risks
+- Venture-scale potential
+- Next steps
+
+### Step 9: Save Report
+
+Offer to save the report as a markdown file:
+- Suggest filename: `market-opportunity-analysis-YYYY-MM-DD.md`
+- Use Write tool to create file
+- Confirm file location with user
+
+## Tips for Best Results
+
+**Do:**
+- Start with bottom-up (most credible)
+- Always triangulate with top-down
+- Cite all data sources
+- Document every assumption
+- Be conservative on SOM
+- Compare to public company benchmarks
+- Explain any data gaps or limitations
+
+**Don't:**
+- Rely solely on top-down
+- Cherry-pick optimistic data
+- Claim >10% SOM without strong justification
+- Mix methodologies inappropriately
+- Ignore competitive context
+- Skip validation steps
+
+## Example Usage
+
+```
+User: /market-opportunity
+
+Claude: I'll help you create a comprehensive market opportunity analysis. Let me start by gathering some context.
+
+What product or service are you analyzing?
+→ "AI-powered email marketing for e-commerce companies"
+
+Who are your target customers?
+→ "E-commerce companies with $1M+ annual revenue in North America"
+
+What's your pricing model?
+→ "Subscription: $50-500/month based on email volume, average $300/month"
+
+[Claude proceeds with analysis, gathering data, calculating TAM/SAM/SOM, and generating report]
+```
+
+## Integration with Other Commands
+
+This command pairs well with:
+- `/financial-projections` - Use SOM to build revenue model
+- `/business-case` - Include market sizing in business case
+
+## Notes
+
+- Market sizing typically takes 30-60 minutes for thorough analysis
+- Quality depends on data availability - explain limitations
+- Update annually as market evolves
+- Conservative estimates build credibility with investors