# Progress — Explorer M3 3

Last visited: 2026-10-01T21:01:00Z

## Status
- **Current Step**: Task Completed — Investigation & test suite design finished.
- **Completed**:
  - Received dispatch assignment and updated DISPATCH.md
  - Initialized and updated BRIEFING.md
  - Inspected `server/world/zone_engine.py` (473 lines) and verified Safe Haven purity
  - Inspected `server/world/procedural_map_engine.py` (412 lines) and designed `get_tile_type` API
  - Formulated backwards-compatible `validate_monster_spawn(zone_id, tx, ty)` signature
  - Verified line budgets: `zone_engine.py` (485 lines $\le 490$), `test_tile_collision.py` (236 lines $\le 300$)
  - Designed, implemented, and empirically verified all 11 unit test cases in `test_tile_collision.py`
  - Inspected `client/webapp/js/engine/collision_engine.js` (218 lines) and verified 2-axis sliding physics
  - Ran regression baseline: 935 unit tests pass, 81 E2E tests pass
  - Authored comprehensive technical report `report.md`
  - Authored 5-component handoff report `handoff.md`
- **Next Steps**:
  - Send message to parent orchestrator with findings and handoff reference.