--- description: Compare architectural scenarios with cost, timeline, complexity, risk, and benefit analysis using parallel agents model: sonnet --- # /scenario-compare Compare multiple architectural scenarios with detailed cost, timeline, complexity, risk, and benefit analysis. Uses three parallel agents to evaluate financial, technical, and risk dimensions simultaneously, then produces a weighted decision matrix with a clear recommendation. ## When to Use This Skill - Choosing between 2-4 architectural approaches for a problem - Comparing build vs buy vs integrate options - Evaluating technology platform alternatives - Preparing options papers for architecture governance boards - Making vendor or product selection decisions ## Usage ``` /scenario-compare vs [vs ] [--criteria cost,risk,time,complexity] ``` ### Parameters | Parameter | Description | Required | |--------------|-----------------------------------------------------|----------| | `scenarios` | 2-4 scenarios separated by `vs` | Yes | | `--criteria` | Comma-separated evaluation criteria (default: all) | No | | `--weights` | Custom weights for criteria (default: equal) | No | ## Instructions ### Phase 1: Define Scenarios For each scenario, gather: | Field | Description | Example | |-------------------|------------------------------------------------|-----------------------------------------| | **Name** | Short label for the scenario | Cloud-Native Rebuild | | **Description** | What this approach entails | Rewrite as microservices on Kubernetes | | **Technology** | Key technologies involved | Kubernetes, PostgreSQL, Kafka | | **Team impact** | What teams need to do | Upskill to containers, hire 2 SREs | | **Timeline** | Estimated delivery timeline | 12-18 months | Also gather evaluation context: - **Decision deadline** — When must the decision be made? - **Budget constraints** — Any hard budget limits? - **Non-negotiables** — Must-have requirements that eliminate options? ### Phase 2: Parallel Scenario Analysis — Agent Team Launch three agents simultaneously using the Task tool. Each agent evaluates all scenarios across one dimension. **Agent 1: Cost and Financial Analyst** (Sonnet) Task: Compare financial implications of each scenario - Calculate setup/implementation costs per scenario - Calculate annual operating costs per scenario (infrastructure, licensing, staffing) - Compute 3-year and 5-year Total Cost of Ownership (TCO) - Calculate Return on Investment (ROI) and payback period - Run sensitivity analysis (best case, expected, worst case — ±20% variance) - Identify hidden costs (migration, training, opportunity cost, technical debt) Return: Financial comparison matrix with TCO, ROI, and sensitivity ranges **Agent 2: Technical and Complexity Analyst** (Sonnet) Task: Compare technical characteristics of each scenario - Score technology stack maturity and ecosystem (0-10) - Score operational complexity (deployment, monitoring, debugging) (0-10) - Score vendor dependency and lock-in risk (0-10) - Assess data migration complexity and approach - Evaluate scalability potential (vertical, horizontal, elasticity) - Assess integration effort with existing systems - Score team skill alignment (current skills vs required skills) (0-10) Return: Technical comparison with radar chart data (5+ dimensions per scenario) **Agent 3: Risk and Timeline Analyst** (Sonnet) Task: Compare risks and delivery timelines - Estimate implementation timeline per scenario (optimistic, expected, pessimistic) - Identify critical path and key dependencies per scenario - Score risks per scenario across categories (technical, organisational, financial, schedule) - Create risk probability x impact matrix per scenario - Identify go/no-go criteria and decision gates - Assess reversibility — how hard is it to change course after committing? Return: Timeline comparison and risk assessment data per scenario ### Phase 3: Synthesise Comparison Combine all agent results: 1. **Build weighted decision matrix** — Score each scenario against all criteria 2. **Create side-by-side comparison** — Visual summary of key differences 3. **Generate recommendation** — Clear recommendation with reasoning 4. **Document trade-offs** — What you gain and lose with each option 5. **Define decision criteria** — Go/no-go checklist for the recommended option **Default Weights:** | Criterion | Weight | Adjustable | |------------------|--------|------------| | Cost (TCO) | 25% | Yes | | Technical fit | 25% | Yes | | Risk | 20% | Yes | | Timeline | 15% | Yes | | Scalability | 15% | Yes | ## Output Format ```markdown # Scenario Comparison: ## Executive Summary **Recommended:** Scenario X — **Confidence:** High/Medium/Low <2-3 sentence justification> ## Scenarios at a Glance | Dimension | Scenario A | Scenario B | Scenario C | |-------------------|-------------------|-------------------|-------------------| | Approach | | | | | Timeline | X months | X months | X months | | 3-Year TCO | £Xk | £Xk | £Xk | | Risk Level | Low/Med/High | Low/Med/High | Low/Med/High | | Complexity | X/10 | X/10 | X/10 | ## Cost Comparison | Cost Category | Scenario A | Scenario B | Scenario C | |---------------------|-------------|-------------|-------------| | Setup costs | £X | £X | £X | | Annual operating | £X | £X | £X | | 3-Year TCO | £X | £X | £X | | 5-Year TCO | £X | £X | £X | | ROI (3-year) | X% | X% | X% | | Payback period | X months | X months | X months | ### Sensitivity Analysis | Scenario | Best Case TCO | Expected TCO | Worst Case TCO | |------------|---------------|--------------|----------------| | A | £X | £X | £X | ## Technical Comparison ### Complexity Radar | Dimension | Scenario A | Scenario B | Scenario C | |-----------------------|------------|------------|------------| | Stack maturity | X/10 | X/10 | X/10 | | Operational complexity| X/10 | X/10 | X/10 | | Vendor lock-in | X/10 | X/10 | X/10 | | Skill alignment | X/10 | X/10 | X/10 | | Scalability | X/10 | X/10 | X/10 | ## Risk Comparison | Risk Category | Scenario A | Scenario B | Scenario C | |------------------|------------------|------------------|------------------| | Technical | | | | | Organisational | | | | | Financial | | | | | Schedule | | | | ## Timeline Comparison | Milestone | Scenario A | Scenario B | Scenario C | |--------------------|-------------|-------------|-------------| | Planning complete | Month X | Month X | Month X | | MVP / Phase 1 | Month X | Month X | Month X | | Full delivery | Month X | Month X | Month X | | Benefits realised | Month X | Month X | Month X | ## Weighted Decision Matrix | Criterion (Weight) | Scenario A | Scenario B | Scenario C | |--------------------------|------------|------------|------------| | Cost — 25% | X/10 | X/10 | X/10 | | Technical fit — 25% | X/10 | X/10 | X/10 | | Risk — 20% | X/10 | X/10 | X/10 | | Timeline — 15% | X/10 | X/10 | X/10 | | Scalability — 15% | X/10 | X/10 | X/10 | | **Weighted Total** | **X.X** | **X.X** | **X.X** | ## Recommendation **Go with: Scenario X — ** ### Why This Scenario ### Key Trade-offs Accepted - ### Go/No-Go Criteria - [ ] ``` ## Examples ### Example 1: Platform Choice ``` /scenario-compare Cloud-native rebuild vs Lift-and-shift vs Hybrid migration ``` ### Example 2: Integration Approach ``` /scenario-compare REST API vs Event-driven vs Batch ETL --weights cost=30,risk=30,time=20,complexity=20 ``` ### Example 3: Build vs Buy ``` /scenario-compare Custom build vs Commercial platform vs Open-source solution --criteria cost,risk,time ``` --- **Invoke with:** `/scenario-compare vs [vs ]`