The execution of Jira expressions is performed on the Jira side, with no direct interaction with the app. For monitoring and testing purposes, however, it’s useful for apps to know when Jira fails to evaluate their expressions, be it due to invalid syntax, semantic bugs caused by unexpected data, or even a temporary glitch on the Jira side.

Add the jira_expression_evaluation_failed webhook to be notified whenever a Jira expression called by the app fails.

{    "webhooks": [      {        "event": "jira_expression_evaluation_failed",        "url": "/jira-expressions-monitoring"      }    ]}

https://developer.atlassian.com/cloud/jira/software/jira-expressions/#monitoring