# BAT-011 Transactional write service split

- Profile: standard
- Status: release-candidate
- Included REQ: REQ-015
- Discovery: dcy-011
- Owner: 렛저장인
- Date (KST): 2026-07-03

## 목표

REQ-015에 따라 account / transaction / budget / category rule-category mutation 경로를 더 좁은 write-oriented application service로 분리한다. 기존 `service.py`, MCP adapter, Streamlit gateway, dashboard 호출부와 response contract는 유지한 채 Phase 4 첫 구현 슬라이스를 실제 코드와 검증 evidence로 마무리한다.

## 산출물

- `jarca_ledger_mcp/application/` write-oriented service modules
- 기존 broad application modules의 compatibility re-export / delegation 정리
- full pytest 및 contract-sensitive regression evidence
- BAT-011 planning/design/implementation/verification documents

## 범위 제한

- import preview/import/rollback split
- advanced workflow(cross-transfer/reconciliation/assets/workbench) 분리
- HTTP adapter 추가
- destructive migration

## 문서

- `planning.md`: Phase 4 첫 delivery plan, risks, validation gate
- `design.md`: write service boundary / delegation design
- `implementation.md`: changed files, execution log, validation commands
- `verification.md`: AC mapping, PASS/FAIL, REQ Implemented decision