Invoice Generator

Generate a professional invoice from natural language or structured input. USE WHEN: - User asks to create an invoice, bill, or payment request - User provides line items, client details, or says "invoice [client] for [work]" - User wants a receipt or proof of payment document DON'T USE WHEN: - User wants a quote, estimate, or proposal (different document structure and intent) - User wants to track invoices, manage accounts receivable, or build an invoicing system - User wants a contract or agreement (use a contract/legal template instead) - User wants to send an invoice via email (this generates the document; sending is a separate step) - User wants a recurring billing setup or subscription management OUTPUTS: Single self-contained .html file, print-ready. User opens in browser → Print → Save as PDF. Clean, professional layout. INPUTS: Sender info, client info, line items (description + qty + price). Optional: invoice number, dates, tax rate, notes, payment terms.

Create professional invoices from text descriptions or structured data.

Workflow

1. Collect invoice details from the user (or parse from prompt):
   • Sender (business name, address, email)
   • Recipient (client name, address, email)
   • Line items (description, quantity, unit price)
   • Invoice number, date, due date
   • Payment terms/methods
   • Tax rate (optional)
   • Notes (optional)
2. Read the template at assets/invoice-template.html
3. Replace placeholders with actual data, calculate totals
4. Save as .html file — user can open in browser and Print → PDF

Calculations

• Subtotal = sum of (quantity × unit price) for each line item
• Tax = subtotal × tax rate
• Total = subtotal + tax
• Always format currency with 2 decimal places

Template Placeholders

Placeholder	Description
{{INVOICE_NUMBER}}	Unique invoice ID
{{INVOICE_DATE}}	Issue date
{{DUE_DATE}}	Payment due date
{{SENDER_*}}	Sender name, address, email, phone
{{CLIENT_*}}	Client name, address, email
{{LINE_ITEMS}}	HTML table rows for items
{{SUBTOTAL}}	Pre-tax total
{{TAX_RATE}}	Tax percentage
{{TAX_AMOUNT}}	Calculated tax
{{TOTAL}}	Final amount due
{{PAYMENT_TERMS}}	Payment instructions
{{NOTES}}	Additional notes

Defaults

• Currency: USD (configurable)
• Tax: 0% unless specified
• Due date: 30 days from invoice date unless specified
• Invoice number: auto-increment or user-specified

Common Mistakes to Avoid

• Don't guess line items — if the user is vague ("invoice them for the work"), ask for specifics (hours, rate, deliverables)
• Don't invent sender details — use what the user provides or ask
• Don't skip the math — always verify subtotal + tax = total. Rounding errors on invoices are unprofessional
• Don't add fake payment links — only include payment methods the user explicitly provides