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: Invoice Template with VAT for UK Sole Traders and Limited Companies
Session id: document-en-gb-invoice-template-with-vat-for-uk-sole-traders-and-limited-companies
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: Invoice Template with VAT for UK Sole Traders and Limited Companies
Target audience: Freelancers, contractors, sole traders, and finance teams issuing invoices in the UK
Industry: Finance and Accounting
Locale: en-GB
Region: United Kingdom
Search intent: Users are looking for a UK invoice example they can download and use to bill clients correctly, especially where VAT applies.
SEO keywords: invoice template uk, vat invoice template uk, uk invoice example, sole trader invoice template uk, limited company invoice uk
Regional nuance: Include VAT-specific fields, payment terms in pounds sterling, and business identity details expected in UK invoicing practices.
Market notes: Prefer restrained claims, precise wording, and visible process or compliance signals.
Template hint: Single-page invoice layout with totals table, VAT breakdown, payment instructions, and optional late payment note.

Linked knowledge digest:
No linked knowledge files.

Recent memory digest:
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