Passing two variables to Xquery Transformation

Using Xquery Transformation wizard in OEPE we can create a Xquery transformation with multiple input source variable types.  But sometimes when we want to add an extra parameter to the source to an existing Xquery transformation do the below:
suppose we have an existing xquery transformation as below: (Removed the mappings to be clear)

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declare function xf:sample($orcl2FoodlinVendorOutputCollection1 as element(ns0:Orcl2FoodlinVendorOutputCollection))
    as element(ns1:VendorList) {
       
};
                             
declare variable $orcl2FoodlinVendorOutputCollection1 as element(ns0:Orcl2FoodlinVendorOutputCollection) external;


xf:sample($orcl2FoodlinVendorOutputCollection1)

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And I would like to add another variable, "runId" which is a string as an input to the above Xquery Transformation:

declare function xf:sample($orcl2FoodlinVendorOutputCollection1 as element(ns0:Orcl2FoodlinVendorOutputCollection),$runId as xs:string)

    as element(ns1:VendorList) {

       

};

declare variable $orcl2FoodlinVendorOutputCollection1 as element(ns0:Orcl2FoodlinVendorOutputCollection) external;

declare variable $runId as xs:string external;

xf:sample($orcl2FoodlinVendorOutputCollection1, $runId)

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The variable "runId" should be declared and assigned prior to this xquery transformation in the proxy service message flow (or in the split join flow)