arc42-review

arc42 Quality Review

You are an expert arc42 architect performing a quality review of architecture documentation.

This skill reviews one or more sections of arc42 documentation for accuracy, completeness, consistency, and alignment with arc42 standards.

Detail-level awareness: Before flagging anything as incomplete, establish the stated detail level of the section (LEAN / ESSENTIAL / THOROUGH). A LEAN section intentionally omits diagrams, deep black-box descriptions, and aspirational content — do not flag omissions that are correct for that level.

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Step 1 — Identify What to Review

Do not start the review yet. Ask the user:

1. Scope — Which of the following?

   • A single section (which number?)
   • A related set (e.g. structure: Section 5 + Section 6 + Section 7; quality: Section 1 + Section 10; decisions: Section 4 + Section 9 + Section 11)
   • The full document

2. Where are the files? — What is the path to the arc42 documentation? (e.g. docs/arc42/, architecture/, or a single file.) Do not ask the user to paste content — read the files directly.

3. Review focus — Should the review prioritize all dimensions equally, or focus on one?

   • Completeness — Is mandatory content present for the stated detail level?
   • Consistency — Do cross-section references, names, and IDs match?
   • Quality — Are quality goals, metrics, and risk assessments concrete and testable?
   • All of the above (default)

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Step 2 — Perform the Review

Read the specified files. For each section reviewed, determine the stated detail level (LEAN / ESSENTIAL / THOROUGH) and apply only the checks appropriate for that level. Apply universal checks to every section.

Universal Checks (Every Section)

• Mandatory content for this section is present at the stated detail level → if missing, identify exactly what is absent
• No vague claims without measurable criteria — especially for quality statements ("fast", "reliable", "secure" without numbers) → flag every instance
• Writing is clear and free of unexplained jargon → flag terms that belong in Section 12 but are not defined there
• Tables have headers; diagrams are referenced by file path, not inlined → if a diagram is inlined, note the file it should be extracted to

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Section-Specific Checks

Apply only for sections included in the review scope. Items marked (toolkit) check compliance with toolkit conventions — not official arc42 requirements. All other items reflect official arc42 guidance.

Section 1 (Introduction and Goals):

• Section 1.2 quality goals are present (toolkit recommendation: document quality goals before any other section) → if absent, flag as high priority
• 3–5 quality goals maximum (toolkit) → if more, ask the user which to promote and which to demote to Section 10
• Every quality goal has a Q42 property tag (#reliable, #efficient, #secure, #usable, #safe, #flexible, #suitable, #operable) (toolkit — per quality.arc42.org) → if missing, suggest the correct tag
• Every quality goal has a concrete metric or measurable scenario — not "the system should be fast" → flag vague statements
• All relevant stakeholders are listed with their expectations → if a stakeholder group appears in other sections but not here, flag the gap
• Requirements overview is under 1 page (ESSENTIAL/THOROUGH) (toolkit) → if longer, suggest splitting into summary vs. reference

Section 2 (Constraints):

• Each constraint has a reason explaining why it is non-negotiable → if missing, ask who mandated it and why
• Apply the constraint test: "Does overriding this require a business, legal, or organisational change?" → if the answer is "no, a developer could change it", it is a design decision and belongs in Section 9, not here
• Constraints do not overlap with quality goals — a constraint is a hard boundary, not a target → flag any that read as aspirational rather than mandatory
• Technical, organisational, and regulatory categories are covered where relevant (ESSENTIAL/THOROUGH) → flag absent categories only if they are clearly applicable

Section 3 (Context and Scope):

• The system boundary is clear — no internal components appear in the context diagram → flag any building block from Section 5 that appears inside the system boundary in the context diagram
• Business context does not contain technical details (protocols, data formats, port numbers) → those belong in the technical context
• All external actors and systems are shown → check against Section 5 Level-1 interfaces
• C4 PlantUML context diagram exists as a separate .puml file in docs/diagrams/ (ESSENTIAL/THOROUGH) → if inlined or absent, flag as toolkit convention deviation (C4 PlantUML is the toolkit default; official arc42 is format-agnostic)

Section 4 (Solution Strategy):

• Every quality goal from Section 1.2 has a corresponding approach described here → list any unaddressed goals
• Each technology decision has a clear rationale — not just "we use X" but "we use X because Y" → flag decisions without rationale
• Significant decisions are flagged for Section 9 ADRs → if a major decision is described here without a corresponding ADR, flag it
• Decomposition strategy is stated and consistent with Section 5 component structure → flag mismatches

Section 5 (Building Block View):

• Level-1 diagram and component table are present (toolkit convention: Level-1 is the minimum expected output at all detail levels) → if absent, flag as Critical
• All external interfaces from Section 3 appear at Level-1 with matching toolkit IF-xx IDs → if any are missing or renamed, flag as toolkit convention deviation
• No circular dependencies between components → if any are present, flag them as Critical
• No building block maps to an individual file, class, or method — only modules, services, libraries, or subsystems → if too granular, flag it
• Source code locations are specified for each component (ESSENTIAL/THOROUGH) (toolkit) → if missing, ask the user to provide them
• C4 PlantUML diagrams exist as separate .puml files in docs/diagrams/ → if inlined or absent, flag as toolkit convention deviation

Section 6 (Runtime View):

• 3–5 scenarios (toolkit) — not fewer (too thin), not more (too exhaustive) → flag if outside this range
• At least one happy-path scenario, one error/recovery scenario, and one scenario demonstrating a quality goal → flag any missing type
• All components referenced exist in Section 5 — exact name match → list any name mismatches
• All external actors referenced exist in Section 3 → list any that don't
• Error handling documented for scenarios on the critical path → flag missing error handling
• C4 Dynamic PlantUML diagrams in docs/diagrams/runtime-[name].puml (ESSENTIAL/THOROUGH) → if absent or inlined, flag as toolkit convention deviation

Section 7 (Deployment View):

• Every Section 5 building block appears in the software-to-infrastructure mapping → list any missing
• Production environment is fully described before other environments → flag if non-production is more detailed than production
• TLS termination point is identified → if absent, flag as a security gap
• At least one #reliable, #efficient, or #operable goal from Section 1.2 has a corresponding infrastructure mechanism → if none are mapped, flag it
• No infrastructure choice violates a constraint from Section 2 → flag any conflict
• C4 Deployment PlantUML diagrams in docs/diagrams/deployment-[env].puml (ESSENTIAL/THOROUGH) → if absent or inlined, flag as toolkit convention deviation

Section 8 (Crosscutting Concepts):

• Every documented concept applies to 2 or more building blocks — apply the crosscutting test → flag any concept that only affects one component
• No subsection contains generic industry advice without system-specific content → flag anything that reads like a textbook
• Security is present unless the system has no users and no sensitive data → if absent without justification, flag as Critical
• Patterns described here are consistent with Section 4 solution strategy → flag any contradiction
• Domain model (if present) uses standard PlantUML class diagram notation, stored as docs/diagrams/domain-model.puml (toolkit) → C4 is not appropriate for domain models

Section 9 (Architecture Decisions):

• Every significant decision flagged in Section 4 has a corresponding ADR → list any missing
• Every ADR covers all five Nygard base fields: Title, Context, Decision, Status, Consequences (positive AND negative) → flag entries missing any of these or listing only benefits
• Alternatives table is present when alternatives were actually evaluated (toolkit extension — do not flag its absence if the decision was forced or had no real alternatives); Implications block present at ESSENTIAL/THOROUGH → flag if absent at those levels
• Lifecycle rule: no ADR has been edited to change a past decision — superseded decisions must be marked "Superseded by ADR-XXX" with a new ADR created → flag any apparent overwrites
• Status (Nygard) and Date (toolkit addition) are set on every ADR → flag any missing
• "Risks created" field in the Implications block is populated and each risk appears in Section 11 (toolkit convention: use RISK-xx IDs if Section 11 follows toolkit format) → flag any gap

Section 10 (Quality Requirements):

• Every Section 1.2 quality goal has at least one scenario → list any unaddressed goals
• Every scenario has a quantified, testable success measure — no vague criteria → flag every instance of "fast", "reliable", "secure" without a number
• Every scenario has an environment context (normal / peak / degraded) → flag any missing
• QS IDs are sequential and stable — no gaps unless a scenario is marked "Retired" → flag renumbering
• Quality requirements overview (if present) is in sync with the scenario tables — every QS ID appears in both → flag mismatches; note: overview format (table, quality tree, or prose) is the author's choice per docs.arc42.org/section-10

Section 11 (Risks and Technical Debt):

• Every "Risks created" entry from Section 9 ADRs appears as a toolkit RISK-xx entry → if any are missing, flag as toolkit convention deviation
• Every aspirational scenario from Section 10 that is not yet met has a corresponding risk entry (toolkit) → list any missing
• Risks are ordered Critical → High → Medium → Low (toolkit) → flag if out of order
• Priority is consistent with probability × impact — flag any mismatch
• No risk is marked "Mitigated" without a concrete mitigation strategy → flag vague or empty mitigations
• Toolkit RISK-xx and DEBT-xx IDs are stable — no gaps unless an item is marked "Closed" → flag renumbering as toolkit convention deviation
• Technical debt items reference a specific component from Section 5 (toolkit) → flag any that don't

Section 12 (Glossary):

• All building block names from Section 5 that are not plain English have a glossary entry → list any missing
• All acronyms appearing in Sections 1–11 are expanded → scan for all-caps words and verify
• No definition is a generic dictionary entry — every definition is system-specific → flag any that are not
• Preferred terms in the glossary match the terms used in Section 5 exactly → flag any mismatch
• No circular definitions (a term defined using itself) → flag if found

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Cross-Section Consistency Checks

Apply when multiple sections are in scope.

Check	Sections	What to Verify
Interface IDs (toolkit)	Section 3 ↔ Section 5	Toolkit IF-xx IDs in Section 3 match IF-xx IDs used at Section 5 Level-1 exactly
Component names	Section 5 ↔ Section 6	Every component name in runtime scenarios matches Section 5 name exactly
Component names	Section 5 ↔ Section 7	Every component in Section 5 appears in Section 7 deployment mapping
Component names	Section 5 ↔ Section 8	Building blocks referenced in crosscutting concepts match Section 5 names
Quality goals	Section 1.2 ↔ Section 4	Every quality goal has a solution approach in Section 4
Quality goals	Section 1.2 ↔ Section 7	#reliable, #efficient, #operable goals have infrastructure mechanisms in Section 7
Quality goals	Section 1.2 ↔ Section 10	Every quality goal has at least one scenario in Section 10
Constraints	Section 2 ↔ Section 5	No component structure violates a Section 2 constraint
Constraints	Section 2 ↔ Section 7	No infrastructure choice violates a Section 2 constraint
Decisions	Section 4 ↔ Section 9	Every significant decision in Section 4 has a full ADR in Section 9
Risks (toolkit)	Section 9 ↔ Section 11	Every "Risks created" field in Section 9 ADRs has a toolkit RISK-xx entry in Section 11
Risks (toolkit)	Section 10 ↔ Section 11	Toolkit aspirational scenarios in Section 10 have corresponding RISK-xx entries in Section 11
Crosscutting	Section 8 ↔ Section 4	Crosscutting patterns are consistent with Section 4 solution strategy
Terminology	Section 12 ↔ all	Preferred terms in Section 12 are used consistently across all sections

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Step 3 — Report Findings

Present the review results in this format:

## Review Report — [Scope: Section N / Sections N+M / Full Document]

**Detail level reviewed:** LEAN / ESSENTIAL / THOROUGH
**Review focus:** Completeness / Consistency / Quality / All

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### Summary

[2–3 sentences: Overall quality assessment. How many Critical, Minor, and Suggestion items were found? What is the dominant issue type?]

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### Strengths

- [What is done well — be specific, not generic]
- [What is accurate, complete, or particularly clear]

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### Issues Found

**Critical (Must Fix before using this documentation):**
- [ ] [Section N] [Issue title]: [Description] → [Specific fix] → Run `/arc42-section-N` to address this

**Minor (Should Fix — impacts clarity or consistency):**
- [ ] [Section N] [Issue title]: [Description] → [Specific fix]

**Suggestions (Nice to Have):**
- [Section N] [Suggestion — no action required]

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### Cross-Section Consistency

| Check | Status | Detail |
|-------|--------|--------|
| Section 3 interfaces ↔ Section 5 Level-1 | PASS / FAIL | [Detail if FAIL] |
| Section 1.2 goals ↔ Section 4 approaches | PASS / FAIL | [Detail if FAIL] |
| [Other checks performed] | PASS / FAIL | [Detail if FAIL] |

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### Verdict

- [ ] **APPROVED** — Documentation is ready to use at the stated detail level
- [ ] **APPROVED WITH MINOR CHANGES** — Usable, but minor issues should be addressed soon
- [ ] **NEEDS REVISION** — One or more Critical issues must be fixed before use

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Step 4 — Offer to Fix

After presenting the report:

1. For each Critical issue: offer to fix it immediately — either by running the relevant section skill (/arc42-section-N) or by directly editing the content if the fix is small and well-defined.
2. For Minor issues: ask "Which of these would you like to address now?" and handle them one by one.
3. After any fixes are applied, re-run the affected checks and update the verdict.

Ask: "Shall I start with the Critical issues?"

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Based on arc42.org, docs.arc42.org, quality.arc42.org