harden

Strengthen interfaces against edge cases, errors, internationalization issues, and real-world usage scenarios that break idealized designs.

MANDATORY PREPARATION

Run the cognition constraint loop (MANDATORY) — see ~/.claude/docs/reference/cognition-constraint-loop.md. (If design-builder loaded this skill only for craft reference, ignore this block and use the craft below.)

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Felt-state framing for edge states (NEW)

Empty states, error states, loading states designed for a user having a bad day, not for the happy-path ideal user. See skills/interfaces-that-feel/SKILL.md — "heartbreak as design brief" section. Otherwise defer to Bakaus + Emil for component-level hardening.

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Assess Hardening Needs

Identify weaknesses and edge cases:

1. Test with extreme inputs:

   • Very long text (names, descriptions, titles)
   • Very short text (empty, single character)
   • Special characters (emoji, RTL text, accents)
   • Large numbers (millions, billions)
   • Many items (1000+ list items, 50+ options)
   • No data (empty states)

2. Test error scenarios:

   • Network failures (offline, slow, timeout)
   • API errors (400, 401, 403, 404, 500)
   • Validation errors
   • Permission errors
   • Rate limiting
   • Concurrent operations

3. Test internationalization:

   • Long translations (German is often 30% longer than English)
   • RTL languages (Arabic, Hebrew)
   • Character sets (Chinese, Japanese, Korean, emoji)
   • Date/time formats
   • Number formats (1,000 vs 1.000)
   • Currency symbols

CRITICAL: Designs that only work with perfect data aren't production-ready. Harden against reality.

Hardening Dimensions

Systematically improve resilience:

Text Overflow & Wrapping

Long text handling:

/* Single line with ellipsis */
.truncate {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

/* Multi-line with clamp */
.line-clamp {
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* Allow wrapping */
.wrap {
  word-wrap: break-word;
  overflow-wrap: break-word;
  hyphens: auto;
}