# BRIEFING — 2026-10-09T05:28:30Z

## Mission
Empirical challenge and gate verification of Milestone M1 Iteration 3 remediation (surgical safeguards against anchor contamination).

## 🔒 My Identity
- Archetype: empirical challenger
- Roles: critic, specialist
- Working directory: c:\Projects\KieuStory\.agents\teamwork\challenger_m1_iter3_2
- Original parent: 97faf5e5-a830-491c-b78c-2af12175badf
- Milestone: M1 Iteration 3 Gate Verification
- Instance: 2 of 2 (Challenger 2)

## 🔒 Key Constraints
- Review-only — do NOT modify implementation code
- Run live empirical tests and probes, zero trust in claims
- Output challenge verdict (APPROVE or REQUEST_CHANGES) in handoff.md

## Current Parent
- Conversation ID: 97faf5e5-a830-491c-b78c-2af12175badf
- Updated: not yet

## Review Scope
- **Files to review**: `05_Production_Pipeline/production_orchestrator.py`, `tests/test_critic_gate.py`, `tests/test_m1_challenger2_probe.py`, `tests/test_adversarial_deep_probe.py`, `.agents/teamwork/worker_m1_remediation_3/handoff.md`
- **Interface contracts**: `PROJECT.md`, `ORIGINAL_REQUEST.md`
- **Review criteria**: Empirical correctness, resilience against adversarial anchor contamination, test suite passes

## Key Decisions Made
- Executed live Python empirical probes for Thúy Vân, compound anchor ep01_scene10_shot07, and attendant ep01_scene06_shot05.
- Executed automated test suites across all tiers (170 tests passing, 0 failures).
- Audited all 192 shots of Ep01: 0 cross-contamination anomalies, 0 keyframe tail leaks on cuts.
- Issued empirical challenge verdict: APPROVE.

## Artifact Index
- `handoff.md` — Verification report and final challenge verdict (APPROVE)
- `progress.md` — Liveness heartbeat and step tracking
- `DISPATCH.md` — Dispatch record from parent orchestrator

## Attack Surface
- **Hypotheses tested**:
  - Adversarial Thúy Kiều reference_start_frame on Thúy Vân: blocked and overridden with canonical fallback (PASS).
  - Adversarial Thúy Kiều reference on compound anchor ep01_scene10_shot07: blocked and resolved to Kim Trọng (PASS).
  - Substring shadowing on attendant tieu_dong_kim_trong: attendant evaluated first, no shadowing by Kim Trọng (PASS).
  - Uppercase and backslash path variations: normalized and properly filtered (PASS).
  - Full 192-shot Ep01 dataset: zero anomalies (PASS).
- **Vulnerabilities found**: None remaining in scope of M1 Iteration 3 remediation.
- **Untested angles**: Hardware-accelerated Muse.ai browser rendering for all 140 shots (deferred to M3/M4).

## Loaded Skills
- None