---
title: "Changes to Runs the price rule engine over a proposed set of line items without\npersisting. Used by the invoice grid to show rule discounts (BOGO,\nspend thresholds, etc.) live as the user edits, while keeping the\nserver as the single source of truth for the math — no client-side\nevaluator to drift."
method: POST
path: "/Invoices/preview-rules"
---

# Changes to Runs the price rule engine over a proposed set of line items without
persisting. Used by the invoice grid to show rule discounts (BOGO,
spend thresholds, etc.) live as the user edits, while keeping the
server as the single source of truth for the math — no client-side
evaluator to drift.

`POST /Invoices/preview-rules`

> Every recorded change to this operation, newest first.

## Timeline

Changed in 1 of 14 revisions.

- **2026-09-11** `503cd0546309`: 3 info

## Changes

- **2026-09-11** `503cd0546309`: 3 info
  - added the new optional request property `patientId` (media type: application/json)
  - added the new optional request property `patientId` (media type: text/json)
  - added the new optional request property `patientId` (media type: application/*+json)

---

[Operation](https://skmtc.dev/clinicos/apis/pawthosx-business-api-v1/docs/Invoices/preview-rules/post.md) - [API](https://skmtc.dev/clinicos/apis/pawthosx-business-api-v1.md) - [Page](https://skmtc.dev/clinicos/apis/pawthosx-business-api-v1/changes/Invoices/preview-rules/post)