Produce structured architectural comparison documents that evaluate two tools, technologies, or solutions against weighted criteria. Use when asked to compare tools, evaluate alternatives, write a technology assessment, create a build-vs-buy analysis, or produce a recommendation report. Also use when someone says 'which should we use', 'should we adopt X or keep Y', 'compare X vs Y', 'evaluate X against Y', or 'is X better than Y'. Handles evaluation framework design, weighted scoring, cost analysis, risk assessment, gap analysis, and actionable recommendations with reversal conditions.
Produce publication-grade architectural comparison documents that evaluate two solutions against weighted criteria derived from organizational requirements. The output follows a 12-section structure with quantified scoring, bidirectional gap analysis, Mermaid architecture diagrams, cost projections, risk matrices, and reversal conditions for every recommendation.
Workflow
Phase 1: Research both solutions
Gather enough context to write authoritative profiles. Research is front-loaded. Weak research produces weak evaluations.
Research checklist:
Identify Solution A and Solution B
For each solution, collect: type, maturity, vendor/maintainer, mechanism, output format, integrations, generation time
Find official documentation, product pages, blog posts, press coverage
Identify pricing model and tiers
Find academic research relevant to the comparison domain
Identify the organization's current usage and existing investments
Document limitations of the research (no hands-on testing, beta status, etc.)
Source priority:
Official documentation and technical specs
Academic research papers (arXiv, conference proceedings)
Press coverage and analyst reports
Community discussions and case studies
Phase 2: Define evaluation framework
Design criteria and weights before scoring. The framework must reflect the organization's priorities, not generic equal-weight distribution.
Framework checklist:
Identify 6-10 evaluation criteria from organizational requirements
Assign percentage weights that sum to exactly 100%
Write a one-sentence rationale for each weight
Define the 1-5 scoring scale with semantic anchors
Verify the highest-weighted criteria reflect the organization's primary constraints
See evaluation methodology for scoring frameworks, weight calibration, and sensitivity analysis techniques.
Phase 3: Write the document
Follow the 12-section structure. Each section has a specific purpose. Do not merge, skip, or reorder sections.
Use the comparison template as a starting point. Copy it and fill in the placeholders. See document structure for section-by-section guidance with examples.
Risk matrix (probability x impact x solution x mitigation)
8
Gap analysis
Map what each solution lacks
Bidirectional capability comparison with "addressable?" column
9
Improvement candidates
Extract value from rejected solution
Specific improvements with effort estimates
10
Recommendation
Decide clearly
Primary recommendation, reversal conditions, next steps, re-eval
A
Sources
Support every claim
Grouped by solution + research, inline citation context
B
Weight justification
Defend the framework
Per-criterion rationale for weight assignment
Executive summary structure
The executive summary contains exactly three elements in this order:
Evaluation scope - What is being compared and why. Correct false equivalences upfront. If one solution covers two stages of the other's pipeline, say so here. This prevents unfair downstream comparisons.
Finding - Neutral factual summary of what the evaluation discovered. No recommendation yet. State the structural relationship between the solutions.
Recommendation - Decisive action with quantified evidence. "Retain Solution B. Do not adopt Solution A." followed by the key numbers and structural reasons.
Core principles
Symmetry
Every data point for Solution A must exist for Solution B. Asymmetric profiles produce biased comparisons. If data is unavailable for one solution, note it as unavailable rather than omitting the field entirely.
Quantification
Numbers replace adjectives. "42x cost differential" not "significantly more expensive". "4.45/5.00 vs 2.05/5.00" not "scored much higher". Show calculations so readers can verify the arithmetic independently.
Intellectual honesty
State limitations of the analysis upfront (Section 2.4)
Include a sensitivity check that stress-tests the conclusion
Provide reversal conditions: what circumstances would change this recommendation
Set a re-evaluation date
Bidirectional gap analysis
Section 8 answers both questions:
What does A have that B lacks?
What does B have that A lacks?
Each gap entry needs an "Addressable?" column explaining whether the gap can be closed internally. One-sided analysis is advocacy, not evaluation. The asymmetry between addressable and structural gaps often tells the real story.
Improvement extraction
The rejected solution exists for a reason. Section 9 extracts specific features worth adopting into the recommended solution. Each improvement needs:
Problem statement (what's missing)
Proposed approach (how to add it)
Effort estimate (small/medium/large with one-sentence reasoning)
This transforms a "don't adopt X" conclusion into a "retain Y and strengthen it with ideas from X" action plan.
Diagrams
Use Mermaid for all architecture diagrams. Include at minimum:
Integration topology for each solution - how each connects to the broader system. Side-by-side comparison reveals structural differences.
Governance/knowledge propagation - how project context, rules, and constraints flow through the system.
Color coding (mandatory):
Red (fill:#f4cccc,stroke:#cc0000): Problems, risks, manual steps, gaps
Green (fill:#d9ead3,stroke:#38761d): Advantages, automation, knowledge sources
Label connections when the relationship is not self-evident:
A -- "manual copy/paste" --> B
Use subgraphs to group related elements:
subgraph knowledge["Project Knowledge"]
direction LR
F["AGENTS.md or CLAUDE.md"]
G["Rules"]
end
Keep each diagram focused on one concept. Two clear diagrams communicate more than one crowded diagram.
Anti-patterns
Pattern
Problem
Fix
Feature checklist
Compares features, not outcomes
Compare what each solution achieves, not what it has
Scores without evidence
Unverifiable claims
Every score needs inline justification in the evaluation matrix
One-sided gap analysis
Reads as advocacy
Always show gaps in both directions
Vague mitigations
"Address the issue" is not actionable
Specify concrete action, estimated cost/effort, and owner
Missing sensitivity check
Conclusion may depend on one criterion
Remove highest-weight criterion and verify the winner still holds
Orphan recommendations
No path to reconsider
Every recommendation needs reversal conditions and re-evaluation date
Hedged conclusions
"Perhaps consider not adopting" lacks conviction
"Do not adopt. Here's why." State the position, then defend it.
Equal-weight distribution
20/20/20/20/20 ignores actual priorities
Weights reflect organizational constraints, not fairness
Hidden cost calculations
"$17,280" without showing the math
Show formula: $24 x 20 x 36 = $17,280
Aesthetic-only diagrams
Pretty diagram with no analytical insight
Every diagram must reveal a structural difference or integration issue
Merged research and scoring
Writing profiles and scoring simultaneously
Complete Phase 2 (framework) before scoring; complete Phase 1 before 2
Quality checklist
Before finalizing, verify every item:
Structure
All 12 sections present and in correct order
Solution profiles are symmetric (same fields for both)
Gap analysis is bidirectional (A has / B lacks AND B has / A lacks)
Arithmetic
Weights sum to 100%
Weighted score calculations are arithmetically correct
Cost projections show formulas, not just totals
Analytical rigor
Sensitivity check included (remove highest-weight criterion, verify winner holds)
Every score has inline evidence (no naked numbers)
Risk matrix covers both solutions
Every recommendation has reversal conditions
Every recommendation has a re-evaluation date
Visual and source integrity
Mermaid diagrams render correctly
Sources cited inline where used and collected in Appendix A
Writing standards
No AI-marker words (see writing guidelines)
No hedging phrases
Third person throughout
Active voice throughout
Sentence case headings
Language
Write all evaluation documents in English. Communicate with the user in their language during the research and drafting process.
1---2name: compare-it3description: Produce structured architectural comparison documents that evaluate two tools, technologies, or solutions against weighted criteria. Use when asked to compare tools, evaluate alternatives, write a technology assessment, create a build-vs-buy analysis, or produce a recommendation report. Also use when someone says 'which should we use', 'should we adopt X or keep Y', 'compare X vs Y', 'evaluate X against Y', or 'is X better than Y'. Handles evaluation framework design, weighted scoring, cost analysis, risk assessment, gap analysis, and actionable recommendations with reversal conditions.4---56# Tool comparison evaluation
78Produce publication-grade architectural comparison documents that evaluate two solutions against weighted criteria derived from organizational requirements. The output follows a 12-section structure with quantified scoring, bidirectional gap analysis, Mermaid architecture diagrams, cost projections, risk matrices, and reversal conditions for every recommendation.
91011## Workflow
1213### Phase 1: Research both solutions
1415Gather enough context to write authoritative profiles. Research is front-loaded. Weak research produces weak evaluations.
1617Research checklist:
1819- [ ] Identify Solution A and Solution B
20- [ ] For each solution, collect: type, maturity, vendor/maintainer, mechanism, output format, integrations, generation time
21- [ ] Find official documentation, product pages, blog posts, press coverage
22- [ ] Identify pricing model and tiers
23- [ ] Find academic research relevant to the comparison domain
24- [ ] Identify the organization's current usage and existing investments
25- [ ] Document limitations of the research (no hands-on testing, beta status, etc.)
2627**Source priority:**
28291. Official documentation and technical specs
302. Academic research papers (arXiv, conference proceedings)
313. Press coverage and analyst reports
324. Community discussions and case studies
3334### Phase 2: Define evaluation framework
3536Design criteria and weights before scoring. The framework must reflect the organization's priorities, not generic equal-weight distribution.
3738Framework checklist:
3940- [ ] Identify 6-10 evaluation criteria from organizational requirements
41- [ ] Assign percentage weights that sum to exactly 100%
42- [ ] Write a one-sentence rationale for each weight
43- [ ] Define the 1-5 scoring scale with semantic anchors
44- [ ] Verify the highest-weighted criteria reflect the organization's primary constraints
4546See [evaluation methodology](references/evaluation-methodology.md) for scoring frameworks, weight calibration, and sensitivity analysis techniques.
4748### Phase 3: Write the document
4950Follow the 12-section structure. Each section has a specific purpose. Do not merge, skip, or reorder sections.
5152Use the [comparison template](assets/comparison-template.md) as a starting point. Copy it and fill in the placeholders. See [document structure](references/document-structure.md) for section-by-section guidance with examples.
5354#### Metadata and framing (Sections 1-2)
5556- [ ] Document metadata (status, date, classification, authors)
57- [ ] Section 1: Executive summary (scope + finding + recommendation)
58- [ ] Section 2: Scope and methodology (in/out table, assumptions, limitations)
5960#### Solution profiles (Section 3)
6162- [ ] Section 3: Solution profiles (symmetric fields for both solutions)
6364#### Scoring and analysis (Sections 4-5)
6566- [ ] Section 4: Evaluation framework (criteria, weights, matrix, sensitivity check)
67- [ ] Section 5: Architectural fit analysis (Mermaid diagrams, integration topology)
6869See [evaluation methodology](references/evaluation-methodology.md) for scoring frameworks and sensitivity analysis.
7071#### Cost, risk, and gaps (Sections 6-8)
7273- [ ] Section 6: Total cost of ownership (assumptions, formulas, multi-year projection)
74- [ ] Section 7: Risk assessment (risk matrix covering both solutions)
75- [ ] Section 8: Gap analysis (bidirectional: A-has/B-lacks AND B-has/A-lacks)
7677#### Synthesis and recommendation (Sections 9-10, Appendices)
7879- [ ] Section 9: Improvement candidates (features from rejected solution worth adopting)
80- [ ] Section 10: Recommendation (primary recommendation, reversal conditions, next steps, re-eval date)
81- [ ] Appendix A: Sources (grouped by solution + research, with inline citation context)
82- [ ] Appendix B: Evaluation criteria weight justification
8384### Phase 4: Validate
8586Use the **Quality Checklist** below. Do not skip the arithmetic verification.
8788See [writing guidelines](references/writing-guidelines.md) for style, voice, formatting, and diagram conventions.
8990## Document architecture
9192The 12-section structure follows a deliberate argument arc: situate the reader (1-2), present the candidates (3), evaluate systematically (4), analyze architecture (5), quantify cost (6), assess risk (7), identify gaps (8), extract improvements (9), recommend (10), support with evidence (A-B).
9394| # | Section | Purpose | Key output |
95| ---- | ---------------------- | ------------------------------------ | ---------------------------------------------------------------- |
96| Meta | Document metadata | Provenance and status | Status, date, classification, authors |
97| 1 | Executive summary | Orient the reader in 30 seconds | Evaluation scope + Finding + Recommendation |
98| 2 | Scope and methodology | Establish boundaries and credibility | In/out scope table, methodology, assumptions, limitations |
99| 3 | Solution profiles | Present candidates symmetrically | Type, mechanism, output structure, integrations, timing |
100| 4 | Evaluation framework | Score with full transparency | Weighted criteria, rubric, matrix, totals, sensitivity check |
101| 5 | Architectural fit | Analyze structural compatibility | Mermaid diagrams, integration topology, governance analysis |
102| 6 | Cost analysis | Quantify the cost differential | Assumptions, multi-year projection table, cost multiplier |
103| 7 | Risk assessment | Identify and classify risks | Risk matrix (probability x impact x solution x mitigation) |
104| 8 | Gap analysis | Map what each solution lacks | Bidirectional capability comparison with "addressable?" column |
105| 9 | Improvement candidates | Extract value from rejected solution | Specific improvements with effort estimates |
106| 10 | Recommendation | Decide clearly | Primary recommendation, reversal conditions, next steps, re-eval |
107| A | Sources | Support every claim | Grouped by solution + research, inline citation context |
108| B | Weight justification | Defend the framework | Per-criterion rationale for weight assignment |
109110## Executive summary structure
111112The executive summary contains exactly three elements in this order:
1131141. **Evaluation scope** - What is being compared and why. Correct false equivalences upfront. If one solution covers two stages of the other's pipeline, say so here. This prevents unfair downstream comparisons.
1152. **Finding** - Neutral factual summary of what the evaluation discovered. No recommendation yet. State the structural relationship between the solutions.
1163. **Recommendation** - Decisive action with quantified evidence. "Retain Solution B. Do not adopt Solution A." followed by the key numbers and structural reasons.
117118## Core principles
119120### Symmetry
121122Every data point for Solution A must exist for Solution B. Asymmetric profiles produce biased comparisons. If data is unavailable for one solution, note it as unavailable rather than omitting the field entirely.
123124### Quantification
125126Numbers replace adjectives. "42x cost differential" not "significantly more expensive". "4.45/5.00 vs 2.05/5.00" not "scored much higher". Show calculations so readers can verify the arithmetic independently.
127128### Intellectual honesty
129130- State limitations of the analysis upfront (Section 2.4)
131- Include a sensitivity check that stress-tests the conclusion
132- Provide reversal conditions: what circumstances would change this recommendation
133- Set a re-evaluation date
134135### Bidirectional gap analysis
136137Section 8 answers both questions:
138139- What does A have that B lacks?
140- What does B have that A lacks?
141142Each gap entry needs an "Addressable?" column explaining whether the gap can be closed internally. One-sided analysis is advocacy, not evaluation. The asymmetry between addressable and structural gaps often tells the real story.
143144### Improvement extraction
145146The rejected solution exists for a reason. Section 9 extracts specific features worth adopting into the recommended solution. Each improvement needs:
147148- Problem statement (what's missing)
149- Proposed approach (how to add it)
150- Effort estimate (small/medium/large with one-sentence reasoning)
151152This transforms a "don't adopt X" conclusion into a "retain Y and strengthen it with ideas from X" action plan.
153154## Diagrams
155156Use Mermaid for all architecture diagrams. Include at minimum:
1571581. **Integration topology for each solution** - how each connects to the broader system. Side-by-side comparison reveals structural differences.
1592. **Governance/knowledge propagation** - how project context, rules, and constraints flow through the system.
160161**Color coding (mandatory):**
162163- Red (`fill:#f4cccc,stroke:#cc0000`): Problems, risks, manual steps, gaps
164- Green (`fill:#d9ead3,stroke:#38761d`): Advantages, automation, knowledge sources
165166**Label connections** when the relationship is not self-evident:
167168```plaintext
169A -- "manual copy/paste" --> B
170```
171172**Use subgraphs** to group related elements:
173174```plaintext
175subgraph knowledge["Project Knowledge"]
176 direction LR
177 F["AGENTS.md or CLAUDE.md"]
178 G["Rules"]
179end
180```
181182Keep each diagram focused on one concept. Two clear diagrams communicate more than one crowded diagram.
183184## Anti-patterns
185186| Pattern | Problem | Fix |
187| --------------------------- | ------------------------------------------------ | ---------------------------------------------------------------------- |
188| Feature checklist | Compares features, not outcomes | Compare what each solution achieves, not what it has |
189| Scores without evidence | Unverifiable claims | Every score needs inline justification in the evaluation matrix |
190| One-sided gap analysis | Reads as advocacy | Always show gaps in both directions |
191| Vague mitigations | "Address the issue" is not actionable | Specify concrete action, estimated cost/effort, and owner |
192| Missing sensitivity check | Conclusion may depend on one criterion | Remove highest-weight criterion and verify the winner still holds |
193| Orphan recommendations | No path to reconsider | Every recommendation needs reversal conditions and re-evaluation date |
194| Hedged conclusions | "Perhaps consider not adopting" lacks conviction | "Do not adopt. Here's why." State the position, then defend it. |
195| Equal-weight distribution | 20/20/20/20/20 ignores actual priorities | Weights reflect organizational constraints, not fairness |
196| Hidden cost calculations | "$17,280" without showing the math | Show formula: $24 x 20 x 36 = $17,280 |
197| Aesthetic-only diagrams | Pretty diagram with no analytical insight | Every diagram must reveal a structural difference or integration issue |
198| Merged research and scoring | Writing profiles and scoring simultaneously | Complete Phase 2 (framework) before scoring; complete Phase 1 before 2 |
199200## Quality checklist
201202Before finalizing, verify every item:
203204### Structure
205206- [ ] All 12 sections present and in correct order
207- [ ] Solution profiles are symmetric (same fields for both)
208- [ ] Gap analysis is bidirectional (A has / B lacks AND B has / A lacks)
209210### Arithmetic
211212- [ ] Weights sum to 100%
213- [ ] Weighted score calculations are arithmetically correct
214- [ ] Cost projections show formulas, not just totals
215216### Analytical rigor
217218- [ ] Sensitivity check included (remove highest-weight criterion, verify winner holds)
219- [ ] Every score has inline evidence (no naked numbers)
220- [ ] Risk matrix covers both solutions
221- [ ] Every recommendation has reversal conditions
222- [ ] Every recommendation has a re-evaluation date
223224### Visual and source integrity
225226- [ ] Mermaid diagrams render correctly
227- [ ] Sources cited inline where used and collected in Appendix A
228229### Writing standards
230231- [ ] No AI-marker words (see [writing guidelines](references/writing-guidelines.md))
232- [ ] No hedging phrases
233- [ ] Third person throughout
234- [ ] Active voice throughout
235- [ ] Sentence case headings
236237## Language
238239Write all evaluation documents in English. Communicate with the user in their language during the research and drafting process.
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Produce structured architectural comparison documents that evaluate two tools, technologies, or solutions against weighted criteria. Use when asked to compare tools, evaluate alternatives, write a technology assessment, create a build-vs-buy analysis, or produce a recommendation report. Also use when someone says 'which should we use', 'should we adopt X or keep Y', 'compare X vs Y', 'evaluate X against Y', or 'is X better than Y'. Handles evaluation framework design, weighted scoring, cost analysis, risk assessment, gap analysis, and actionable recommendations with reversal conditions. It is listed under Docs & Writing on SkillMD.
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