# BRIEFING — 2026-10-03T08:36:00Z

## Mission
Adversarially challenge and empirically verify the Real-Browser Cocos Human Journey testing stack, Playwright runner, 8-step screenshots, telemetry metrics, and the UX analysis report.

## 🔒 My Identity
- Archetype: challenger_browser_telemetry
- Roles: critic, specialist
- Working directory: c:\Projects\FreeExile\.agents\teamwork\challenger_browser_telemetry
- Original parent: cecb05d6-3b1b-4c90-84e7-b52ac4e7697c
- Milestone: cocos_human_journey_qa_verification
- Instance: 1 of 1

## 🔒 Key Constraints
- Review-only — do NOT modify implementation code
- Run verification code directly (empirical proof required; do not trust worker claims)
- Target files/dirs in FreeExile project; agent metadata only in .agents/teamwork/

## Current Parent
- Conversation ID: cecb05d6-3b1b-4c90-84e7-b52ac4e7697c
- Updated: 2026-10-03T08:29:30Z

## Review Scope
- **Files to review**: `tools/qa/run_cocos_human_journey.py`, `docs/qa/reports/screenshots/*`, `docs/qa/reports/COCOS_CLIENT_MIGRATION_AND_HUMAN_UX_REPORT.md`
- **Interface contracts**: `ORIGINAL_REQUEST.md`, `PROJECT.md`
- **Review criteria**: Real-browser execution, 8 step screenshots validity & non-emptiness, telemetry (FPS, heap, latency), UX report empathy & quantitative analysis

## Key Decisions Made
- Executed `python tools/qa/run_cocos_human_journey.py` independently: Passed with avg 64.6 FPS, zero errors.
- Inspected all 8 PNG files in `docs/qa/reports/screenshots/`: verified 1280x720 RGB, non-blank, accurate scene captures.
- Verified TypeScript compilation in `client/cocos`: `npx tsc --noEmit` exited 0 with 0 errors.
- Verified `pytest tests/e2e_cocos`: 178 passed in 0.43s.
- Verified telemetry: Heap 2.85 MB (<< 65 MB target), 172 DOM nodes (<< 380 target), 0 unhandled errors. Noted that p99 frame time (91.7ms) and jank ratio (1.97%) reflect synthetic pause from 8 synchronous Playwright screenshot encodings during probe measurement.
- Verdict reached: APPROVE.

## Artifact Index
- `tools/qa/run_cocos_human_journey.py` — Playwright test script (verified)
- `docs/qa/reports/screenshots/` — 8 journey screenshots (verified)
- `docs/qa/reports/COCOS_CLIENT_MIGRATION_AND_HUMAN_UX_REPORT.md` — UX evaluation report (verified)
- `tests/e2e_cocos/` — 178 E2E tests (verified)

## Attack Surface
- **Hypotheses tested**:
  * Hypothesis 1: Are screenshots pre-cooked mock files or dynamically generated? Tested by running runner freshly; timestamps and randomized character names ("Diệp Tố Tâm") updated live.
  * Hypothesis 2: Does TypeScript client actually typecheck cleanly? Verified via `npx tsc --noEmit` (0 errors).
  * Hypothesis 3: Does zero-residual momentum actually brake at frame 0? Verified empirically (`stopped_velocity_x == 0`).
  * Hypothesis 4: Is p99 frame latency indicative of render jank? Evaluated: frame spike correlates directly with 8 synchronous Playwright screenshot disk saves.
- **Vulnerabilities found**: None that break gameplay or contracts; minor note on Playwright probe measuring screenshot latency into jank statistics.
- **Untested angles**: Native Metal GPU pipeline on physical iOS hardware (simulated via Web preview harness).

## Loaded Skills
- None