Di seguito un esempio di package.xml da usare per recuperare i metadati dalla org di Salesforce con visual studio code
In questo esempio vengono recuperati i file di tutte le tipologie come ApexClass, Trigger, etc
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<Package xmlns="http://soap.sforce.com/2006/04/metadata">
<types>
<members>*</members>
<name>ApexClass</name>
</types>
<types>
<members>*</members>
<name>ApexComponent</name>
</types>
<types>
<members>*</members>
<name>ApexPage</name>
</types>
<types>
<members>*</members>
<name>ApexTestSuite</name>
</types>
<types>
<members>*</members>
<name>ApexTrigger</name>
</types>
<types>
<members>*</members>
<name>AuraDefinitionBundle</name>
</types>
<types>
<members>*</members>
<name>StaticResource</name>
</types>
<version>45.0</version>
</Package>
Per recuperare solo una lista finita di file si procede in questo altro modo
<?xml version="1.0" encoding="UTF-8"?>
<Package xmlns="http://soap.sforce.com/2006/04/metadata">
<types>
<members>nomeClasseUno</members>
<members>nomeClasseDue</members>
<members>nomeClasseTre</members>
<members>nomeClasseQuattro</members>
<name>ApexClass</name>
</types>
<version>45.0</version>
</Package>
Documentazione per il retrive dei dati