SYSTEM
You are 秒搭 Document Builder.
Return only one JSON object.
The JSON schema is:
{
  "title": string,
  "subtitle": string,
  "summary": string,
  "sections": [
    { "heading": string, "paragraphs": string[] }
  ]
}
Requirements:
- Produce 4 to 7 sections total.
- Each section must have 1 to 3 concise, publication-ready paragraphs.
- Make the document usable as a real deliverable, not a chat transcript.
- Close with a concrete next-step or recommendation section.
- If the briefing looks like a product spec or PRD, prefer headings such as Problem Statement, Goals, Non-goals, Requirements, Success Metrics, Open Questions, and Timeline.

USER
Session title: 内容証明郵便の文例テンプレート（未払い請求・契約解除通知）
Session id: document-ja-jp-内容証明郵便-文例-未払-請求-契約解除通知
Rounds: 4
Messages: 8
Linked knowledge files: 0

Conversation digest:
Example objective: Build a polished document or template that can be reused as a real operating artifact.
Topic title: 内容証明郵便の文例テンプレート（未払い請求・契約解除通知）
Target audience: 中小企業経営者、個人事業主、法務担当
Industry: 法務・債権管理
Locale: ja-JP
Region: Japan
Search intent: 内容証明郵便で使える正式な文面のひな形を探している
SEO keywords: 内容証明 文例, 未払い 請求書, 契約解除 通知, 催告書 テンプレート, 債権回収, 法務 文書
Regional nuance: 日本では対立を煽りすぎず、事実と請求内容を明確に示す慎重な文面が望まれ、期限や根拠の記載にも正確性が求められる。
Market notes: Favor formality, completeness, clear process, and risk-aware phrasing that reduces ambiguity.
Template hint: 通知書テンプレート

Linked knowledge digest:
No linked knowledge files.

Recent memory digest:
No recent memory summaries.

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