design-rules

Design Rules

Purpose

Guidelines for the /designer command to produce high-quality design specs that reduce plan-review iterations.

Instructions

Step 1: Load at /designer startup

Read this SKILL.md for overview. Supporting files loaded on-demand per phase.

Step 2: Use phase-driven loading

• Phase 3 (PROPOSE) → read Spec Quality for approach evaluation criteria
• Phase 3.5 (CRITIQUE) → read Critique Lenses for the adversarial lens set + disposition forcing-function
• Phase 4 (WRITE SPEC) → read Design Checklist for self-verification
• Phase 5 (USER GATE) → verify checklist before presenting to user

Spec Quality Criteria

Criterion	Required	Check
Context describes current state	Yes	Not just "add X" but "currently Y exists, need X because Z"
Scope has IN and OUT	Yes	OUT items have explicit reasons
At least 2 approaches compared	Yes	With pros/cons for each
Selected approach has rationale	Yes	References constraints from requirements
Key decisions are numbered	Yes	Each has rationale and impact
Risks have severity and mitigation	Yes	HIGH risks must have concrete mitigation
Acceptance criteria are verifiable	Yes	Each can be checked as pass/fail

Anti-Patterns

Anti-Pattern	Why Bad	Fix
"The obvious approach is..."	Skips exploration, may miss better options	Always compare at least 2
Spec without OUT scope	Scope creep during planning	Explicitly list what's excluded
Vague acceptance criteria ("works well")	Can't verify	Make criteria concrete and testable
No risks identified	Every design has risks	Identify at least 1 per approach
Copying task description as context	No analysis	Describe current state, not just goal

Common Issues

Designer skips CLARIFY phase

Cause: Task seems clear. Fix: Even "clear" tasks benefit from scope IN/OUT confirmation. At minimum, confirm scope.

User rejects all approaches

Cause: Missing constraint not captured. Fix: Ask: "What constraint am I missing?" — don't generate more approaches without new information.

References

• Spec Quality — detailed quality criteria, approach evaluation matrix
• Critique Lenses — adversarial lens set, anti-theater forcing function (Phase 3.5)
• Design Checklist — phase-by-phase self-verification