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: Modèle de lettre de mise en demeure de paiement
Session id: document-fr-fr-modèle-de-lettre-de-mise-en-demeure-de-paiement
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: Modèle de lettre de mise en demeure de paiement
Target audience: PME, indépendants, services comptables et administratifs
Industry: Recouvrement et gestion
Locale: fr-FR
Region: France
Search intent: Obtenir un modèle de mise en demeure de paiement prêt à envoyer
SEO keywords: lettre mise en demeure paiement, modèle relance impayé, mise en demeure facture impayée, exemple courrier recouvrement, lettre impayé client
Regional nuance: Employer un ton ferme mais mesuré, conforme aux usages français, avec références précises aux factures, date limite et envoi recommandé si nécessaire.
Market notes: Balance brand tone and clarity, keep the narrative polished, and avoid generic sales wording.
Template hint: Courrier formel avec objet, références, paragraphe de mise en demeure et signature.

Linked knowledge digest:
No linked knowledge files.

Recent memory digest:
No recent memory summaries.

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