# BRIEFING — 2026-10-01T02:44:00Z

## Mission
Empirically re-challenge and verify the EXP progression curve math following the 0.35 factor fix in Milestone M1 Iteration 2.

## 🔒 My Identity
- Archetype: empirical_challenger
- Roles: critic, specialist
- Working directory: c:\Projects\FreeExile\.agents\teamwork\challenger_m1_progression_1_gen2
- Original parent: 6f4a2aa2-4315-4660-8cb7-8352a7220c95
- Milestone: M1 Iteration 2
- Instance: 2 of 2

## 🔒 Key Constraints
- Review-only — do NOT modify implementation code
- Empirical verification required: must run verification code directly, do NOT trust claims or logs
- Adhere to Teamwork file conventions (.agents/teamwork/<my_dir> only for writes)

## Current Parent
- Conversation ID: 6f4a2aa2-4315-4660-8cb7-8352a7220c95
- Updated: not yet

## Review Scope
- **Files to review**: `server/world/level_progression_curve.py`, `server/world/game_design_matrix_service.py`, `server/world/game_design_matrix_seeder.py`, `tests/e2e/test_level_progression_e2e.py`
- **Interface contracts**: `c:\Projects\FreeExile\.agents\teamwork\orchestrator_4\PROJECT.md`
- **Review criteria**: Empirical validation of 7 mathematical checks, Level 99->100 Delta EXP ratio constraints, overflow safety, monotonicity, zero drift, and hygiene compliance.

## Attack Surface
- **Hypotheses tested**:
  * Check 1: Monotonicity across 100 levels -> Confirmed (0 violations).
  * Check 2: Level 1-20 cumulative EXP < 0.1% -> Confirmed (0.0134%).
  * Check 3: Level 99->100 Delta EXP ratio >= 30% of 1-98 and 25-35% of lifetime -> Confirmed (ratio_vs_98=35.0%, ratio_vs_lifetime=25.925926%).
  * Check 4: Death penalty tiers matching exact values -> Confirmed (0 mismatches).
  * Check 5: Level gap penalty constants -> Confirmed (0 mismatches).
  * Check 6: SQLite DB persistence & zero drift -> Confirmed (100 rows, 13 cols, 0 drift).
  * Check 7: Integer bounds & 64-bit headroom -> Confirmed (safe in signed INT64 and float53).
- **Vulnerabilities found**: None.
- **Untested angles**: All target angles for Milestone M1 tested.

## Loaded Skills
None

## Key Decisions Made
- Executed `challenge_exp_curve.py`, all 7 checks returned PASS [OK].
- Executed `pytest` on unit and E2E suites: 52 passed, 6 xfailed (for M2/M3).
- Verified `verify_game_design_matrix.py --sync`, mypy, and `check_code_and_doc_hygiene.py --strict`.
- Formulated verdict: APPROVED.

## Artifact Index
- `report.md` — Detailed empirical challenge report
- `handoff.md` — 5-component handoff report