Problem Definition

Smart Values can get pretty complex when building an intensive rule.
Feedback on how the system will interpret what is being written without having to execute the Rule would be incredibly helpful.

Suggested Solution

The website https://regex101.com has an explainer & match information section on their right.
The explainer states what each section of the regex is in clear language.
The match information section shows what the

My suggestion is to provide equivalents for Automation Rules.
For example, the explainer is fairly straightforward. For this smart value:

{{issue.parent.reporter.accountId.length()}}

The explainer would have:

• issue - accesses the currently targeted or "focused" issue, optional
• parent - traverses to the issue's parent issue, making it the new target of issue smart values
• reporter - accesses the reporter field on the currently targeted issue
• accountId - returns a User's Atlassian Account ID
• length() - counts the number of characters in a string entity and returns the count

Then, the "value information" section would show:

• issue - ABC124 - Source: The Triggering Issue
• parent - ABC123 - Source: Parent to ABC124
• reporter - John Doe - Source: Reporter on ABC123
• accountId - 557058:f58131cb-b67d-43c7-b30d-6b58d40bd077 - Source: Atlassian Identity
• length() - 43 - Source: Java & math

Workaround

There is no currently available workaround except to use the Log Action and keep checking the Audit Log by re-running the Automation Rule until the desired output is achieved.