Ask Copilot Agent created using Copilot Studio about custom metadata

I created an Agent using Copilot Studio, and i define the source to be a SharePoint online site.

The site contain a document library which contain custom column named "MCProjectLeadUse" of type People or Group, 

Now if i directly asked the agent about the MCProjectLeadUser for a document named "Salary.docx", i will get this reply that it can not find this custom column:-

So the only way i find it to fix this, is to create a Power Automate, which accept the entered file name , and return the custom field as follow:-

and call this power automate from the copilot, as follow:-

but is there a more appropriate approach to do this? as doing this inside Power Automate, means that we are not fully benefiting from AI capabilities, but rather return the values inside structured power automate flows using the traditional none-AI approach. So what if we add new custom column? or remove existing columns? can  not we force the Agent to understand those custom properties out of the box? instead of using power automate?

Thanks