# IncrementalAuthorizationFields

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

Structured field bundle for the
`IncrementalAuthorization`
operation. An incremental authorization sends a fresh auth message to the
brand network on top of the existing approved hold, increasing the held amount by the
requested increment. The issuer can decline.

## Fields
- `incrementalAmount` (number(double)): The additional authorization amount to request, in major currency units (e.g. `10.00`  = $10). The new `Total_Auth_Amt` after a successful incremental auth equals the  existing approved amount plus this value. Must be strictly positive: clearing or  reducing an existing hold is the reversal flow's job, not this one. (greater than 0)
- `reason` (string): Optional caller-supplied reason / merchant note (e.g. `"Estimated tab plus 20% tip"`).  Surfaced on the close-stage history entry and the customer-facing receipt. Not validated  against any controlled vocabulary: purely informational. Conditional: When Reason is not empty. Max length: 500. (nullable)
- `isEmpty` (boolean): `true` when the bundle carries no actionable information. An  incremental authorization with a non-positive increment has nothing to ask the  brand for and is a caller error, rejected before anything is sent to the processor. (read only)

## See also

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