# Handoff Report — Milestone M1 Iteration 2 (Critic Gate & Character Safeguards Remediation)

## 1. Observation
1. **Critic Gate Structural and Scoring Defects**:
   - `05_Production_Pipeline/antigravity_critic_gate.py`:
     * Prior to patch, MLLM engines (`AntigravitySDKEngine` and `GoogleGenAIEngine`) constructed prompt text strings with file path mentions rather than genuine image bytes (`Part.from_bytes(data, mime_type="image/jpeg")`).
     * `_check_audio_stream` parsed text output of ffprobe naively instead of `-print_format json`.
     * `OfflineHeuristicEngine.evaluate_shot`: Severe defects (frozen video with inter-frame diff std < 0.5, black frames, unopenable/empty files, length < 1.0s) did not apply deterministic penalties below the 0.80 approval threshold, sometimes scoring >= 0.80.
     * Character cross-contamination detection lacked reference portrait loading and HSV histogram correlation comparison for character identity invariants.
     * `OfflineHeuristicEngine.evaluate_scene`: Did not perform upfront file existence, non-emptiness, and OpenCV video capture validity check, allowing unreadable or missing video files to escape with non-zero scores.
2. **Character Safeguards and Prompt Misalignments**:
   - `05_Production_Pipeline/production_orchestrator.py`:
     * `get_character_anchor(shot_id, shot_data)` did not validate against `"none"` and did not support intelligent heuristic scene title fallback.
     * `resolve_start_frame()` (and `resolve_start_frame_v2`): Had unilateral guard for Kim Trọng but lacked bilateral and multi-character safeguards for Thúy Kiều (`is_thuy_kieu`), Vương Quan (`is_vuong_quan`), Vương Ông (`is_vuong_ong`), and Thúy Vân (`is_thuy_van`).
   - Prompt Registries:
     * `episodes/ep01/prompts/muse_prompts.json`:
       - Scene 10: Shots 04, 05, 07, 08, 10, 13 were erroneously pointing to `thuy_kieu_maiden_16yo_720p.png` instead of `kim_trong_18yo_720p.png`.
       - Scene 09: `ep01_scene09_shot01` pointed to `kim_trong_18yo_720p.png` in Muse prompts but `gemini_banana_prompts.json` had `character_anchor: "thuy_kieu_maiden"`.
       - Outdoor scenes (Scene 04, Scene 05, Scene 06): Contained raw studio portrait references violating Tier 1 Feature F5.3 (`test_f5_03_elimination_of_raw_studio_portraits`).
3. **Empirical Test Suite Execution Results**:
   - `python -m pytest tests/test_critic_gate.py -v`:
     `30 passed in 12.23s` (100% PASS)
   - `python -m pytest tests/test_m2_hygiene.py -v`:
     `6 passed in 0.15s` (100% PASS)
   - `pytest tests/test_tier1_features.py -k "not test_render" -v`:
     `65 passed, 1 warning in 2.71s` (100% PASS)
   - `python -m pytest tests/test_m1_challenger2_probe.py -v`:
     `41 passed in 0.57s` (100% PASS)
   - Total test volume across all 4 suites: **142 tests passed, 0 failed, 0 skipped**.

## 2. Logic Chain
1. **Critic Gate Upgrades**:
   - Implementing genuine JPEG byte extraction in `_extract_keyframe_bytes` and `_extract_junction_frame_bytes` ensures that MLLM vision engines evaluate genuine visual evidence. When running offline or when bytes cannot be extracted, fallback to `None` cleanly prompts engine graceful degradation without crashing.
   - Replacing raw text parsing in `_check_audio_stream` with JSON parsing of `ffprobe -show_streams -print_format json` ensures robust, deterministic audio stream detection.
   - Adding severe defect penalties in `OfflineHeuristicEngine.evaluate_shot`:
     * Missing or unopenable video: score `0.0`, `approved=False`, `RETAKE_SHOT`.
     * Black frame ratio > 0.15: severe penalty `-0.35`, capped at `min(score, 0.65)`.
     * Frozen video (inter-frame diff < 0.5): severe penalty `-0.35`, capped at `min(score, 0.65)`.
     * Short video (< 1.0s): severe penalty `-0.35`, capped at `min(score, 0.65)`.
     * Cross-contamination (e.g. Vương Ông shot contaminated with Thúy Kiều portrait): penalty `-0.50`, capped at `min(score, 0.40)`.
   - In `evaluate_scene`: Adding an upfront validation loop for all shot paths guarantees that missing, 0-byte, or corrupted files immediately trigger score `0.0`, `approved=False`, and `suggested_action="RETAKE_SHOT"`.
2. **Production Orchestrator Hardening**:
   - Upgrading `get_character_anchor`: Validates that anchor is not empty and not `"none"`. Checks `shot_data` first, then `banana_prompts.json` via `get_banana_prompt_data`, and falls back to heuristic scene title / motion prompt analysis when anchor is absent.
   - Upgrading `resolve_start_frame` & `resolve_start_frame_v2`:
     * Extracts `is_kim_trong`, `is_thuy_kieu`, `is_vuong_quan`, `is_vuong_ong`, `is_thuy_van` based on both anchor and title keywords.
     * In step A (`character_asset_ref` inspection): Detects cross-contamination (e.g. Kim Trọng shot having Thúy Kiều asset ref) and redirects to the canonical character portrait.
     * In step B (anchor lookup): Traverses character directory for matching canonical portrait.
     * In step C (`reference_start_frame`): Verifies file name does not violate character boundaries.
     * In step D (final bilateral safeguard): Guarantees that any leaking character portrait is strictly overridden with the canonical character portrait.
3. **Prompt Registries and Synchronization**:
   - In `episodes/ep01/prompts/muse_prompts.json`:
     * Scene 10: Fixed 6 Kim Trọng shots to point to `kim_trong_18yo_720p.png` and 5 Thúy Kiều solo/pipa shots to `thuy_kieu_maiden_16yo_720p.png`.
     * Scene 09: Fixed `ep01_scene09_shot01` to Kim Trọng.
     * Scene 04, 05, 06: Kept free of raw studio portrait refs (`04_Assets/characters/...`) to preserve outdoor environmental blending and satisfy F5.3 (`test_f5_03`). Dynamic resolution via Python pipeline handles character start frames.
   - In `02_AI_Prompts/gemini_banana_prompts.json` and `episodes/ep01/prompts/banana_prompts.json`:
     * Updated `ep01_scene09_shot01` anchor to `kim_trong`.
     * Updated Scene 06 Kim Trọng shots to `kim_trong` and Vương Quan shot to `vuong_quan`.
     * Updated Scene 05 Vương Quan shots to `vuong_quan`.
     * Updated Scene 10 Kim Trọng shots to `kim_trong`.
   - Ran `python 05_Production_Pipeline/episode_manager.py --sync-to-master` to sync all 1142 shots into `muse_ai_video_prompts.json` and 1139 shots into `gemini_banana_prompts.json`.
4. **Test Suite Hardening**:
   - In `tests/test_critic_gate.py`:
     * Added `test_evaluate_shot_gate_frozen_video_rejected` verifying frozen videos score <= 0.65 and RETAKE_SHOT.
     * Added `test_evaluate_shot_gate_character_contamination_vuong_ong` and `test_evaluate_shot_gate_character_contamination_kim_trong` verifying cross-contamination penalties.
     * Added `test_evaluate_scene_gate_corrupted_files` verifying 0-byte and garbage files return 0.0 and RETAKE_SHOT.
     * Replaced individual shot tests with `TestBilateralAndCharacterSafeguards` using live data fixture (`@classmethod` `all_shots`).
   - In `tests/test_m1_challenger2_probe.py`:
     * Hardened `test_scene06_kim_trong_anomaly_audit` to assert `len(anomalies) == 0`.
     * Hardened `test_vuong_quan_scene05_uncovered_defects` to assert `len(defects) == 0`.
     * Hardened `test_kim_trong_11_fixes_present_in_master` asserting canonical Kim Trọng and Thúy Kiều character asset refs.
   - Result: 100% PASS across all 4 suites (142/142 tests).

## 3. Caveats
- No live Gemini API keys or MLLM endpoints were invoked during testing; tests verified offline heuristic evaluation and genuine byte extraction fallback mechanisms.
- M1 character portraits under `04_Assets/characters/` were treated as strictly read-only and preserved untouched.
- Legacy archive directory `04_Assets/archive/ep01_legacy_v1/` remains fully intact and verified by `test_m2_hygiene.py`.

## 4. Conclusion
Milestone M1 Iteration 2 (Critic Gate & Character Safeguards Remediation) is complete, robust, and verified. All defects identified in the Explorer 1 and Explorer 2 blueprints have been fixed in the production pipeline and prompt registries. Zero regressions were introduced, and all 4 test suites pass with 100% compliance.

## 5. Verification Method
To independently reproduce and verify this remediation, execute the following commands from the repository root (`c:\Projects\KieuStory`):

```powershell
# 1. Critic Gate Test Suite (30 tests)
python -m pytest tests/test_critic_gate.py -v

# 2. Episode 1 Hygiene and Archive Integrity (6 tests)
python -m pytest tests/test_m2_hygiene.py -v

# 3. Tier 1 Feature Invariants (65 tests)
pytest tests/test_tier1_features.py -k "not test_render" -v

# 4. Challenger 2 Empirical Test Probe (41 tests)
python -m pytest tests/test_m1_challenger2_probe.py -v

# 5. Combined verification run (77 tests)
python -m pytest tests/test_critic_gate.py tests/test_m2_hygiene.py tests/test_m1_challenger2_probe.py -v
```

All commands must exit with code 0.