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+---
+id: capability.design.whynot-system
+name: Whynot Design System
+summary: 'Framework-agnostic visual language for whynot prototype/market-signal artefacts: design tokens,
+  drop-in CSS, Lit-based web components usable from React/Django/Vue/plain HTML, and Django template adapters.'
+owner: whynot-design
+status: draft
+domain: consumer
+tags:
+- design-system
+- web-components
+- frontend
+maturity:
+  discovery:
+    current: D3
+    target: D4
+    confidence: medium
+    rationale: README documents a clear three-layer architecture (tokens, CSS, Lit web components) plus
+      a companion DesignSystemIntroduction.md describing propagation pipeline, versioning, and A1 staging
+      relative to whynot-control.
+  availability:
+    current: A2
+    target: A3
+    confidence: high
+    rationale: 'Published as `@whynot/design` (not private: `"private": false` in package.json), ships
+      a CLI (`whynot-design` bin), tokens/CSS/JS source, and Django adapters — genuinely consumable across
+      frameworks today, not just planned.'
+external_evidence:
+  completeness:
+    level: C2
+    confidence: low
+    basis: scope_vs_intent_and_consumer_expectations
+    satisfied_expectations:
+    - framework-agnostic Lit web components (same `<wn-button>` usable in React/Django/Vue/plain HTML)
+    - design tokens as source of truth
+    - Django adapter partials
+    - package is publicly consumable (not private)
+    broken_expectations: []
+    out_of_scope_expectations: []
+  reliability:
+    level: R1
+    confidence: low
+    basis: consumer_quality_signals
+    known_reliability_risks:
+    - cross-framework consumption claims not independently verified in every target framework during this
+      sweep
+discovery:
+  intent: Give whynot's prototype and market-signal artefacts a consistent, deliberately-unfinished visual
+    language, consumable identically across any framework via framework-agnostic web components rather
+    than per-framework reimplementation.
+  includes:
+  - design tokens (tokens/*.json)
+  - drop-in CSS (src/styles/*.css)
+  - Lit-based web components (src/elements/*.js)
+  - Django adapter partials
+  excludes:
+  - whynot-control's product/business logic itself (see whynot-control)
+  assumptions: []
+  use_cases: []
+  research_memos: []
+availability:
+  current_level: A2
+  target_level: A3
+  current_artifacts:
+  - '`@whynot/design` npm package (public)'
+  - '`whynot-design` CLI'
+  target_artifacts: []
+  consumption_modes:
+  - library import (npm)
+  - cli
+  - django template adapter
+relations:
+  depends_on: []
+  supports: []
+  related_to: []
+evidence:
+  documentation:
+  - README.md
+  - DesignSystemIntroduction.md
+  tests:
+  - tests/
+  - test-results/
+  consumer_feedback: []
+  bug_reports: []
+  incidents: []
+consumer_guidance:
+  recommended_for:
+  - whynot-family apps needing a consistent, framework-agnostic visual language across React/Django/Vue/plain
+    HTML
+  not_recommended_for:
+  - consumers wanting a themed (non-neutral) visual language, or needing whynot-control's business logic
+    itself
+  known_limitations:
+  - cross-framework consumption not independently re-verified in every target framework this sweep
+promotion_history: []
+---
+
+# Whynot Design System
+
+## Overview
+
+`@whynot/design` is the framework-agnostic visual language for whynot's prototype and market-signal artefacts: design tokens as source of truth, drop-in CSS, and Lit-based web components that work identically across React, Django, Vue, and plain HTML, plus Django adapter partials — publicly published, not a private/internal-only package.
+
+## Assessment notes
+
+### Discovery
+
+README documents a clear three-layer architecture (tokens, CSS, Lit web components) plus a companion DesignSystemIntroduction.md describing propagation pipeline, versioning, and A1 staging relative to whynot-control.
+
+### Availability
+
+Published as `@whynot/design` (not private: `"private": false` in package.json), ships a CLI (`whynot-design` bin), tokens/CSS/JS source, and Django adapters — genuinely consumable across frameworks today, not just planned.
+
+### Completeness
+
+First-pass honest assessment from the REUSE-WP-0017 coverage campaign
+(reuse-surface). No external consumer feedback exists yet; levels reflect
+scope-vs-intent documentation quality, not internal code quality.
+
+### Reliability
+
+No production consumer telemetry exists yet; reliability level is
+intentionally conservative pending REUSE-WP-0019 reuse-telemetry evidence.
+
+## Promotion checklist
+
+- [x] ID follows `capability.<domain>.<name>` pattern
+- [x] Maturity enums match `specs/CapabilityMaturityStandard.md`
+- [x] `external_evidence` is populated separately from `maturity`
+- [ ] Relations reference valid capability IDs (none yet)
+- [x] Index entry added in `registry/indexes/capabilities.yaml`
diff --git a/registry/indexes/capabilities.yaml b/registry/indexes/capabilities.yaml
index f944e47..b226cfe 100644
--- a/registry/indexes/capabilities.yaml
+++ b/registry/indexes/capabilities.yaml
@@ -1,4 +1,22 @@
 version: 1
-updated: '2026-06-16'
+updated: '2026-07-06'
 domain: helix_forge
-capabilities: []
+capabilities:
+- id: capability.design.whynot-system
+  name: Whynot Design System
+  summary: 'Framework-agnostic visual language for whynot prototype/market-signal artefacts: design tokens,
+    drop-in CSS, Lit-based web components usable from React/Django/Vue/plain HTML, and Django template
+    adapters.'
+  vector: D3 / A2 / C2 / R1
+  domain: consumer
+  status: draft
+  owner: whynot-design
+  path: registry/capabilities/capability.design.whynot-system.md
+  tags:
+  - design-system
+  - web-components
+  - frontend
+  consumption_modes:
+  - library import (npm)
+  - cli
+  - django template adapter