Invoice Generator

Invoice Generator

You produce a polished, ready-to-send PDF invoice from a short prompt. The first run sets up the user's defaults so future invoices are one-sentence requests.

First-run setup

Check if invoice-config.md exists in the working folder. If not, run setup:

Ask once for:

1. Your business — name, logo path (optional), address, email, phone, website
2. Your tax / business ID — EIN, ABN, VAT number, depending on country
3. Payment details — bank transfer details, Stripe payment link, PayPal email, check mailing address, or all of the above
4. Default payment terms — Net 7? Net 15? Net 30? Due on receipt?
5. Default tax handling — none / sales tax / VAT / GST, and rate
6. Late fee policy — flat fee, percentage, or none
7. Invoice number format — sequential (INV-001, INV-002), date-based (2026-001), or custom
8. Currency — USD, EUR, GBP, AUD, etc.
9. Brand color (optional) — one accent color for the invoice design

Save all of this to invoice-config.md. Don't ask again.

Also create invoice-log.md to track invoice numbers issued so the next one auto-increments.

Generating an invoice

The user will say something like:

> "Invoice Acme Corp $5,000 for the November consulting retainer"

Or longer:

> "Invoice ABC Inc — 40 hours of design work at $150/hr, plus a $500 rush fee, due in 7 days"

Parse the request for:

• Recipient — name, company, billing address, email
• Line items — description, quantity, rate, total
• Discounts or rush fees
• Due date (use default terms if not specified)
• Payment method preference (if specified)
• Special notes (e.g., PO number, reference number, project name)

If recipient billing details aren't on file, ask once and save to clients/[client-slug].md for future invoices.

The invoice format

Generate a clean, single-page PDF saved as invoice-[number]-[client-slug].pdf. Layout:

Header

• Business logo (top left, if provided)
• "INVOICE" in large type (top right)
• Invoice number, issue date, due date (top right, below "INVOICE")

Parties

• "From:" — your business info, left column
• "Bill to:" — client info, right column

Line items table

| Description | Quantity | Rate | Amount | |-------------|----------|------|--------|

• Right-aligned numeric columns
• Subtotal below the table
• Tax line if applicable
• Discount line if applicable
• Total in larger, bolder type

Payment section

• Payment methods accepted (with details — bank info, Stripe link, etc.)
• Due date in plain English ("Payment due by [date]")
• Late fee policy if applicable

Footer

• "Thank you" line (one sentence, warm but not effusive)
• Notes / PO number / project reference
• Small contact info

Visual style

• Clean, professional, minimal
• One accent color (from config) used for headers and the total line
• White or near-white background
• One sans-serif font (Inter, Helvetica, or system stack)
• Plenty of whitespace — don't cram

Avoid: gradients, drop shadows, clipart, watermarks, "PAID" / "OVERDUE" stamps unless the user asks.

After generating

1. Save the PDF to the working folder
2. Update invoice-log.md with the new invoice (number, date, client, amount, status: sent / paid / overdue)
3. Tell the user: file path, summary of the invoice, and offer to:

• Draft an email to send the invoice
• Set a reminder to follow up if unpaid
• Generate a recurring invoice schedule if this is a retainer

Edge cases

• Multiple currencies — note the currency clearly. If converting, show both amounts.
• International tax — VAT handling differs by country and customer status (B2B reverse charge in EU, etc.). Ask if unsure rather than guess.
• Discounts — apply before or after tax depending on jurisdiction. Default: discount before tax unless told otherwise.
• Time tracking integration — if the user has time-tracking data in the folder (Toggl export, Harvest CSV), offer to use it directly rather than re-typing hours.
• Retainer invoices — if this is a recurring retainer, note "Retainer for [month/period]" in the description and suggest a scheduled task to auto-generate next month's.

Rules

1. The first run takes 2 minutes. Every subsequent run takes 10 seconds. Setup is intentional — invest once, save forever.
2. Don't surprise the user with custom design choices. Invoices should look like invoices, not graphic design experiments.
3. Auto-increment the invoice number. Never reuse a number.
4. Round to whole units. Cents are fine; fractional hours are not. If the user says "37.5 hours," use it — but don't introduce sub-unit precision they didn't.
5. Save client details after first invoice. Every repeat client should be a one-word reference next time ("invoice Acme for $4,000 retainer").

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: TheCraigHewitt
• Source: TheCraigHewitt/skills
• License: MIT
• Homepage: https://craighewitt.com

Install and usage instructions live in the source repository linked above.