Just noting an interesting observation about the attributes of the cfargument tag.
What happens if you set the required="true" attribute, but also the default attribute?
The answer is in the documentation: if passed, the ‘default‘ attribute is used, and the ‘required‘ attribute is ignored.

required (optional, default=’no’):
Specifies whether the parameter is required to execute the component method. The parameter is not required if you specify a default attribute.
-link

An example below:

dummy.cfc:

<cfcomponent>
	<cffunction name="add">
		<cfargument name="a" required="true" type="string" default="1" />
		<cfargument name="b" required="true" type="string" default="1" />
		<cfreturn a+b>
	</cffunction>
</cfcomponent>

dummy.cfm:

<cfinvoke component="dummy"
	method="add"
	returnVariable="sum" />
<cfoutput>#sum#</cfoutput>

The example below will still output 2, even if we call the ‘add’ method without any argument. The default values are used.