Scenarios.cs

public record Person([FromRoute][Required][StringLength(1, 8)] string id);

public record Person
{
    public Person(string id) => Id = id;
    
    [FromRoute][Required][StringLength(1, 8)] 
    public string Id { get; init; }
}

public class Person
{
    public Person(string id) => UserId = id;
    
    [FromRoute][Required][StringLength(1, 8)] 
    public string UserId { get; }
}

public class Person
{
    private string _id;

    public Person([JsonProperty("UserId")][MaxLength(4)] string id) => _id = id;
}

public class Person
{
    public Person([Required][StringLength(1, 8)] string id) => UserId = int.Parse(id);
    
    [Range(1, 9999)]
    public int UserId { get; }
}