---
agentTools:
  projectIndex: https://developer.zylo.com/llms.txt
---

# June 23, 2025

Various improvements and fixes for Contracts resource.

## Added

### Contracts

* Added better documentation around `billing_frequency` to the Contracts resource to indicate what values are valid.

## Fixed

### Contract Line Items

* Moving forward `application_id` is no longer able to be set to `null`.

## Removed

### Contracts

* The `external_source_link` is no longer able to be modified.