Hussh Frontend Cache Coherence Skill

Purpose and Trigger

• Primary scope: frontend-cache-coherence
• Trigger on cache-first screen UX, route TTL policy, stale-while-revalidate resources, warm-cache audits, and reviewer-backed cache checks.
• Avoid overlap with frontend-architecture, frontend-native-surface-mapper, and security-audit.

Coverage and Ownership

• Role: spoke
• Owner family: frontend

Owned repo surfaces:

1. hushh-webapp/lib/cache
2. hushh-webapp/lib/services/cache-service.ts
3. hushh-webapp/lib/cache/cache-sync-service.ts
4. hushh-webapp/scripts/architecture/audit-cache-coherence.mjs
5. hushh-webapp/cache-coherence-screen-manifest.generated.json
6. docs/reference/architecture/cache-coherence.md
7. docs/reference/quality/app-surface-design-system.md

Non-owned surfaces:

1. frontend
2. frontend-architecture
3. frontend-native-surface-mapper
4. security-audit

Do Use

1. Screen-level cache posture audits and warm-cache UX fixes.
2. Resource hooks, TTL policy, background refresh, and cache invalidation contract work.
3. Reviewer-backed checks proving protected routes do not block on loaders when cache is warm.

Do Not Use

1. Broad route inventory or package-script ownership; use frontend-architecture.
2. Route/API/native/plugin mapping; use frontend-native-surface-mapper.
3. PKM protocol, vault key, or encrypted storage boundary changes; use security-audit.

Read First

1. docs/reference/architecture/cache-coherence.md
2. docs/reference/quality/app-surface-design-system.md
3. hushh-webapp/cache-coherence-screen-manifest.generated.json
4. hushh-webapp/scripts/testing/verify-signed-in-routes.mjs
5. hushh-webapp/lib/cache/use-stale-resource.ts

Workflow

1. Classify the prompt claim as existing, partial, missing, future-state, wrong-direction, or needs-verification.
2. Run the cache and manifest checks before trusting screen coverage.
3. Preserve the security posture: decrypted PKM, vault keys, and consent secrets stay memory-only.
4. Use useStaleResource or a service-owned resource wrapper for warm-cache rendering.
5. Route all mutation invalidation through CacheSyncService or a domain service that delegates to it.
6. Use reviewer env identity only through the existing resolver; never hardcode reviewer values.
7. Treat performance as part of cache coherence: choose the safest available UX path before showing a blocking loader.
8. Verify route/cache KPI coverage for changed screens: readiness, resource resolution, refresh completion, and warmup where applicable.
9. Keep performance events metadata-only: route ID, resource class, cache tier, freshness, result, duration bucket, and footprint bucket. Never emit raw cache keys, user IDs, workflow IDs, PKM payloads, prompts, or decrypted values.
10. When a route split reuses an existing workspace, regenerate and verify cache-coherence-screen-manifest.generated.json; every canonical nested route needs explicit route readiness/resource-class coverage even if the cache posture is inherited from the parent workspace.

Handoff Rules

1. If route inventory, package scripts, or generated surface-map shape changes, hand off to frontend-architecture.
2. If native parity or API dependency mapping changes, hand off to frontend-native-surface-mapper.
3. If PKM/vault persistence semantics change, hand off to security-audit.
4. If browser proof policy changes, hand off to quality-contracts.

Required Checks

cd hushh-webapp && npm run verify:cache
cd hushh-webapp && npm run audit:cache-coherence
cd hushh-webapp && npm run verify:analytics
cd hushh-webapp && npm run verify:surface-map
cd hushh-webapp && npm run verify:service-boundary