Template syntax

Templates are HTML/CSS documents with Handlebars placeholders. The fields you reference become the data you send to /v1/generate.

Placeholders & loops

<h1>Invoice {{invoice_number}}</h1>
<p>Bill to: {{customer.name}}</p>

<table>
  {{#each items}}
  <tr>
    <td>{{this.description}}</td>
    <td>{{currency this.amount ../currency}}</td>
  </tr>
  {{/each}}
</table>

{{#if notes}}<p class="note">{{notes}}</p>{{/if}}

Helpers

The following helpers are available for formatting (they never compute business logic):

• {{currency total "USD"}} — format a number as currency
• {{date issue_date "medium"}} — format a date (short, medium, long, full, or iso)
• {{number qty 2}} — format a number with fixed decimals
• {{sum items "amount"}} — total a field across an array
• math: add, subtract, multiply, divide
• comparisons (for {{#if (eq a b)}}): eq, ne, gt, gte, lt, lte, and, or

Full helper list: currency, number, date, add, subtract, multiply, divide, sum, eq, ne, gt, gte, lt, lte, and, or.

Templates format, your code computes

Keep business math out of templates — pass computed values like subtotal, tax and total in your data. This keeps generation deterministic and avoids rounding bugs.

Page size, fonts & images

• Set the page size with CSS @page { size: A4 } (or Letter). PaperFox adds a sensible default if you omit it.
• Use page-break-inside: avoid on table rows so long tables paginate cleanly.
• Use system/standard font stacks or self-hosted @font-face. Reference a logo via a {{logo_url}} placeholder or a data: URI.

The fastest way to build one is the AI authoring editor — describe the document and refine the result live.