# SendInvoiceInput

A model the API reference uses in a request or a response. The operation pages link every field typed as this model here.

Input for the full invoice send workflow: issue (if draft), generate PDF, create pay link, send notification.

## Fields
- `customMessage` (string): Optional custom message to include in the notification email. Conditional: When CustomMessage is not null. Max length: 2000. (nullable)
- `paymentLinkExpiryHours` (integer(int32)): Payment link expiry in hours. Defaults to 720 (30 days) if not specified. Conditional: When PaymentLinkExpiryHours is not null. Must be > 0. (nullable)
- `viewTokenExpiryDays` (integer(int32)): View token expiry in days. Defaults to 90 days if not specified. Conditional: When ViewTokenExpiryDays is not null. Must be > 0. (nullable)

## See also

- [All documentation](https://devportal.demo.winkpg.io/llms.txt): the machine-readable index of every public page on this site.