> For the complete documentation index, see [llms.txt](https://ai-os-and-trend-finder.gitbook.io/ai-os-and-trend-finder-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://ai-os-and-trend-finder.gitbook.io/ai-os-and-trend-finder-docs/.spec_system/archive/sessions/phase27-session05-velocity-dynamics-upgrade/implementation_summary.md). # Implementation Summary **Session ID**: `phase27-session05-velocity-dynamics-upgrade` **Completed**: 2026-06-13 **Duration**: 0.8 hours *** ## Overview Session 05 completed the Trend Finder velocity dynamics upgrade by deriving acceleration, statistical significance, and burst context from existing private history instead of adding new sources or AI calls. The runtime now builds bounded evidence-count and delta histories, merges 14-day sparkline context for burst detection, and applies only capped burst support to momentum so the existing six-factor score contract remains stable. The browser contract stays additive and bounded. Legacy payloads parse with explicit unavailable dynamics states, score panels render acceleration, significance, and burst rows, and Engine Replay explains the capped support without exposing private snapshot paths or raw history. *** ## Deliverables ### Files Created | File | Purpose | Lines | | ------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------ | ----- | | `.spec_system/specs/phase27-session05-velocity-dynamics-upgrade/spec.md` | Session scope and implementation contract. | 379 | | `.spec_system/specs/phase27-session05-velocity-dynamics-upgrade/tasks.md` | 20-task checklist and completion tracker. | 94 | | `.spec_system/specs/phase27-session05-velocity-dynamics-upgrade/implementation-notes.md` | Task-by-task implementation record. | 505 | | `.spec_system/specs/phase27-session05-velocity-dynamics-upgrade/security-compliance.md` | Security and GDPR review. | 95 | | `.spec_system/specs/phase27-session05-velocity-dynamics-upgrade/validation.md` | Validation report and quality gates. | 274 | | `scripts/lib/ai-runtime/velocity-dynamics.ts` | Pure acceleration, significance, burst, normalization, and capped-support helpers. | 386 | | `scripts/lib/ai-runtime/__tests__/velocity-dynamics.test.ts` | Unit tests for hand-computed dynamics values, caps, sorting, and unavailable states. | 143 | | `src/extensions/trend-finder/components/__tests__/score-breakdown.test.tsx` | Component tests for available and unavailable dynamics rows. | 52 | | `.spec_system/specs/phase27-session05-velocity-dynamics-upgrade/IMPLEMENTATION_SUMMARY.md` | Session closeout summary. | 141 | ### Files Modified | File | Changes | | ------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------- | | `.spec_system/PRD/phase_27/PRD_phase_27.md` | Marked Session 05 complete, updated progress to 5/12, recorded completion details, and advanced upcoming work to Session 06. | | `.spec_system/state.json` | Added Session 05 to completed sessions and history; cleared current session. | | `package.json` | Bumped patch version from 0.1.307 to 0.1.308. | | `README.md` | Updated the displayed project version to 0.1.308. | | `scripts/lib/ai-runtime/historical-context.ts` | Added bounded evidence-count and delta history per canonical topic. | | `scripts/lib/ai-runtime/scoring.ts` | Derived velocity dynamics, merged sparkline context, and applied capped burst support to momentum. | | `scripts/extensions/trend-finder/collector.ts` | Passed historical sparklines into scoring and emitted sanitized aggregate dynamics counters. | | `scripts/extensions/trend-finder/engine-trace.ts` | Added sanitized dynamics state and burst support trace summaries. | | `src/extensions/trend-finder/schema.ts` | Added bounded velocity dynamics schemas, defaults, and legacy fallback handling. | | `src/extensions/trend-finder/view-model.ts` | Added dynamics labels, tones, descriptions, detail copy, and ARIA labels. | | `src/extensions/trend-finder/components/score-breakdown.tsx` | Rendered acceleration, significance, and burst rows with unavailable states. | | `src/extensions/trend-finder/components/trend-card.tsx` | Passed topic velocity dynamics into score breakdown. | | `src/extensions/trend-finder/components/signal-radar.tsx` | Passed velocity dynamics into existing score panels. | | `src/extensions/trend-finder/views/hidden-gems-view.tsx` | Passed velocity dynamics into hidden-gems score panels. | | `src/extensions/trend-finder/views/watchlist-view.tsx` | Passed velocity dynamics into watchlist score panels. | | `src/extensions/trend-finder/engine-replay-model.ts` | Added dynamics scoring factors and capped burst proof copy. | | `src/extensions/trend-finder/engine-trace.ts` | Added browser trace schema fields and default text for dynamics proof. | | `src/extensions/trend-finder/fixtures.ts` | Added available, unavailable, and trace-safe dynamics fixture states. | | `scripts/extensions/trend-finder/__tests__/collector.test.ts` | Covered collector dynamics trace counters. | | `scripts/lib/ai-runtime/__tests__/historical-context.test.ts` | Covered evidence-count history and delta-history assembly. | | `scripts/lib/ai-runtime/__tests__/scoring.test.ts` | Covered missing history, low samples, capped burst support, and repeated scoring idempotency. | | `scripts/lib/ai-runtime/__tests__/topic-identity.test.ts` | Updated typed historical context fixture compatibility. | | `src/extensions/trend-finder/__tests__/view-model.test.ts` | Covered dynamics view-model rows and unavailable labels. | | `src/lib/__tests__/trend-finder-engine-replay.test.tsx` | Covered dynamics rows in Engine Replay scoring proof. | | `src/lib/__tests__/trend-finder-schema.test.ts` | Covered dynamics defaults, bounds, malformed fallback, and legacy payload parsing. | *** ## Technical Decisions 1. **Pure runtime math boundary**: Velocity dynamics live in `scripts/lib/ai-runtime/velocity-dynamics.ts`, keeping historical math out of React components and browser parsing. 2. **Additive browser compatibility**: New schema fields default to explicit unavailable states so old payloads and fixtures continue to parse. 3. **Capped burst support**: Burst can add at most four momentum points and does not change the six score factor weight keys. 4. **Sanitized trace output**: Collector and Engine Trace expose only aggregate counters, enum states, and capped support points. 5. **Projected UI rendering**: Score panels consume view-model rows and ARIA labels instead of raw scoring internals. *** ## Test Results | Metric | Value | | -------- | ------- | | Tests | 3377 | | Passed | 3377 | | Coverage | Not run | Commands validated: * `bun run test` - passed, 273 files and 3377 tests. * `bun run typecheck` - passed. * `bun run typecheck:scripts` - passed. * `bun run lint` - passed with 3 existing warnings. * `bunx prettier --check [session files and touched code]` - passed. * `git diff --check` - passed. * Touched-file ASCII and CRLF validation - passed. *** ## Lessons Learned 1. Velocity context needs evidence-count deltas, not score deltas, to stay aligned with the Phase 27 momentum contract. 2. Significance is safer as an unavailable state below minimum samples or zero variance than as a weak numeric guess. 3. Burst detection is useful only when it is visibly capped and separated from the core six-factor weights. 4. Validation-time consumers must pass additive display fields through every existing score panel, not only trend cards. *** ## Future Considerations Items for future sessions: 1. Session 06 can classify lifecycle stages from the new acceleration, significance, and burst states. 2. Session 07 can use the same bounded history context for convergence and trajectory visuals. 3. A future SQLite observation store can replace snapshot-file derivation while preserving the browser-safe dynamics contract. *** ## Session Statistics * **Tasks**: 20 completed * **Files Created**: 9 * **Files Modified**: 25 * **Tests Added**: 9 test files added or updated * **Blockers**: 0 resolved --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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