# BRIEFING — 2026-10-01T20:53:30Z

## Mission
Adversarially challenge and review Iteration 2 fixes for the POE2 Map System (chunk rendering, LRU cache thrashing, boundary conditions, SAT diamond culling, test suite verification).

## 🔒 My Identity
- Archetype: teamwork_preview_reviewer
- Roles: reviewer, critic
- Working directory: c:\Projects\FreeExile\.agents\teamwork\reviewer_m2_fix_2
- Original parent: 1cc48fc5-ce57-4f48-8964-24cab4bfcacc
- Milestone: M2 Fix 2
- Instance: 1 of 1

## 🔒 Key Constraints
- Review-only — do NOT modify implementation code
- Actively check for integrity violations: hardcoded test results, facade implementations, bypassed tasks, fabricated logs/attestations
- Adhere to GEMINI.md and AGENTS.md directives
- Produce an evidence chain of observations and logical inferences
- Write handoff.md following 5-component protocol (Observation, Logic Chain, Caveats, Conclusion, Verification Method)
- Communicate completion to parent via send_message

## Current Parent
- Conversation ID: 1cc48fc5-ce57-4f48-8964-24cab4bfcacc
- Updated: 2026-10-01T20:47:02Z

## Review Scope
- **Files to review**:
  - `client/webapp/js/engine/tile_map_renderer.js`
  - `tools/perf/map_render_benchmark.js`
  - `tools/perf/stress_test_lru_cache.js`
  - `tests/e2e/test_poe2_map_system_e2e.py`
  - `tests/unit/test_waypoint_safe_radius.py`
  - `tools/lint/check_code_and_doc_hygiene.py`

## Key Decisions Made
- Executed all 5 mandatory verification benchmarks and test suites; all passed with 100% success (81/81 e2e, 17/17 safe radius, 935/935 unit tests, 0 hard cap violations).
- Constructed independent adversarial test scripts:
  1. Full-map grid sweep verifying stationary cache invariance on $390 \times 844$ (0 re-bakes everywhere, max visible = 8).
  2. Multi-viewport stress test identifying that viewports $> 390 \times 844$ (e.g. Pro Max $430 \times 932$) reach 9 chunks visible and will experience thrashing with fixed 8 slots.
  3. Ground-truth geometric culling analysis revealing `padD = 48` allows minor false negatives for elevated tiles (`elev > 0`, up to 18px), while flat tiles have strictly 0 false negatives.
  4. 15 boundary and corrupt input edge cases verified passing without exceptions.
- Integrity verification: No hardcoded results, dummy implementations, or shortcuts detected.

## Artifact Index
- `BRIEFING.md` — Agent working memory
- `progress.md` — Liveness and heartbeat
- `DISPATCH.md` — Assignment log
- `handoff.md` — Final review and challenge report

## Review Checklist
- **Items reviewed**: `tile_map_renderer.js`, `map_render_benchmark.js`, `stress_test_lru_cache.js`, all test suites.
- **Verdict**: APPROVE
- **Unverified claims**: All verified independently.

## Attack Surface
- **Hypotheses tested**:
  - Stationary camera thrashing at all map points on $390 \times 844$: PASSED (0 re-bakes).
  - Multi-viewport scaling ($430 \times 932$, $768 \times 1024$): CHALLENGED (needs dynamic slot scaling for tablet/Pro Max).
  - SAT culling false negatives: PASSED for flat floor, CHALLENGED for elevated tiles with `padD = 48`.
  - Extreme coordinates & unmounted viewports: PASSED.