Change Propagation (Cascading Update)

After the initial 3-MD set is in place, any modification request must check for cascading impact across downstream MDs and code. This skill is the dispatcher for those follow-up edits — it keeps the upstream → downstream chain consistent and writes cross-linked change-history entries.

Trigger Detection

Two ways to enter this skill:

1. Natural language change request — the user says something like "FR-3 한도 바꿔", "개발방향 §5 결정 다시", "Task 4 단계 추가". The main agent recognizes the intent and invokes this skill.
2. Explicit override — the user says "요구사항만 고쳐, 하위는 건드리지 마". This phrase forces partial-scope behavior; the skill applies the upstream edit but skips the cascading step.

Change Level Identification

If the request is ambiguous, ask the user once: "이건 요구사항 변경인가요, 개발방향 변경인가요?" Do NOT guess silently.

Impact Matrix

Code edits never cascade upward to 요구사항 or 개발방향. The reasoning is unchanged; only the implementation moved.

Checklist

• Trigger Detection — 변경 신호 catch
• Change Level Identification — 어느 레벨 변경 (요구사항 / 개발방향 / 구현계획서 / 코드)
• Impact Matrix 적용 — 영향 받는 downstream MD 식별
• Process Flow — cascading 갱신 실행
• User Approval — 사용자 게이트
• After Approval — change-history cross-linked entry append

Process Flow

digraph propagation {
    "Detect change request" [shape=box];
    "Identify change level" [shape=diamond];
    "Apply impact matrix" [shape=box];
    "Compose impact list" [shape=box];
    "Show user: 'These will be touched'" [shape=box];
    "User approves scope?" [shape=diamond];
    "Apply edits to all approved targets" [shape=box];
    "Cross-link CH-ids\n(연관 항목)" [shape=box];
    "Done" [shape=doublecircle];

    "Detect change request" -> "Identify change level";
    "Identify change level" -> "Apply impact matrix";
    "Apply impact matrix" -> "Compose impact list";
    "Compose impact list" -> "Show user: 'These will be touched'";
    "Show user: 'These will be touched'" -> "User approves scope?";
    "User approves scope?" -> "Apply edits to all approved targets" [label="approved"];
    "User approves scope?" -> "Apply edits to all approved targets" [label="partial → narrowed"];
    "User approves scope?" -> "Done" [label="cancel"];
    "Apply edits to all approved targets" -> "Cross-link CH-ids\n(연관 항목)";
    "Cross-link CH-ids\n(연관 항목)" -> "Done";
}

User Approval Format

When presenting the impact list, use this structure:

변경 요청 감지: <change level> 변경 ("<short summary of the change>")

영향 매트릭스 적용 결과 — 함께 갱신될 항목:
1. <slug>-requirements.md §3 FR-3 (직접 변경)
2. <slug>-tech-design.md §6 위험 (한도 증가에 따른 잔액 검증 강도 재평가)
3. <slug>-implementation-plan.md Task 4 (한도 검증 로직)
4. 코드 src/wallet/service.py:withdraw() (한도 상수)

진행 / 부분 진행(번호 선택) / 취소 중 선택해주세요.

The Korean closing line is intentional — that's what the user reads.

After Approval

For each approved target:

1. Apply the edit (directly via Edit, or by re-entering the relevant skill — brainstorming for 요구사항, tech-design for 개발방향, writing-plans for 구현계획서)
2. Invoke change-history to append the entry
3. Cross-link: every entry from the same propagation batch shares the 연관 항목 field listing the other CH-ids in the batch

Example entry skeleton (one of N in a batch):

### [2026-05-02 14:30] [요구사항-수정]
- **id**: CH-20260502-007
- **이유**: 사용자 요청, 한도 5만 → 10만
- **무엇이**: <slug>-requirements.md §3 FR-3
- **영향범위**: <slug>-tech-design.md §6 (위험 재평가), <slug>-implementation-plan.md Task 4 (검증 로직)
- **연관 항목**: CH-20260502-008 (개발방향), CH-20260502-009 (구현계획서), CH-20260502-010 (코드)

Anti-Patterns

Red Flags

Acceptance

A propagation run is correct when ALL hold:

1. The user saw the impact list before any downstream edit
2. Every approved target produced a change-history entry
3. All entries in the batch share 연관 항목 with the other CH-ids in the batch
4. Code-only edits did not modify <slug>-requirements.md or <slug>-tech-design.md (reverse-cascade is forbidden)
5. (v2.2.2+) .html 동봉본이 존재하는 feature 라면 마지막 단계에서 안내문 출력 → 이 변경으로 .html 이 stale 됐을 수 있음. 필요시 /sync-html <slug> (자동 호출 X — stale 허용 철학 보존)

Related Skills

• change-history — entry recording (called for each target)
• brainstorming / tech-design / writing-plans — re-entered when an upstream MD edit needs a re-dialogue
• verifying-spec — re-runs after upstream MD changes if scope is non-trivial
• risk-annotation — invoked again if cascading touches code
• /sync-html <slug> (v2.2.2+) — .html 동봉본 stale 시 사용자 수동 호출 (자동 호출 X, stale 허용 철학)