Is there a way to set a default value to a function documentation text box for a custom connector?

I'm making a custom connector, but my user will use only one server (each user has is own server), so I'm wondering if there's a way to set a default value from code to the text box? (or any way to pass from a text file), so my user would not need to type the URL every time he uses the connector and star the authentication process?

SetupServerTemplate = type function (

     url as (
        Uri.Type meta [
            Documentation.FieldCaption = "Server URL",
            Documentation.FieldDescription = "The URL server"

        ]
    )
) as function meta [
    Documentation.Name = "My custom connector",
    Documentation.FieldDescription = "Connector to retrieve data from the server"
];

I have in mind that probable I can use something like: 
Source = File.Contents("C:\Users\TheUser\Documents\MyServer.txt"),
TheServer= Text.FromBinary(Source)

Documentation.AllowedValues = TheServer

But seems that is not possible to read files from a custom connector