Suggestion to Improve Validator Argument Syntax in RAIL

[takeshiyagiuchi]

I'm using Guardrails with RAIL and finding it very helpful, but I have a suggestion.

Currently, when specifying validators in RAIL, the arguments for validators are passed using space-separated values, like this:

<string name="subject" 
        description="the subject of the given dialogue" 
        validators="hub://guardrails/valid_length: 1 3"
        on-fail-guardrails_valid_length="reask">

In this format, you must provide all preceding arguments, even if you only want to specify the later ones. I believe it would improve readability if the argument names were included explicitly, like this:

<string name="subject" 
        description="the subject of the given dialogue" 
        validators="hub://guardrails/valid_length: min=1 max=3"
        on-fail-guardrails_valid_length="reask">

Additionally, I wonder if the on-fail behavior could be included directly in the validator arguments, like this:

<string name="subject" 
       description="the subject of the given dialogue" 
       validators="hub://guardrails/valid_length: min=1 max=3 on-fail='reask'">

This could eliminate the need for users to figure out attributes like on-fail-guardrails_valid_length, improving both clarity and ease of use.

However, I’m not sure if there’s a specific reason for the current design. This is just my suggestion, and I'd appreciate any feedback or insights you could provide.