In RakuAST::Doc::Block§

See primary documentation in context for method add-config.

$block.add-config(
  'allow',
  RakuAST::QuotedString.new(
    processors => <words val>,
    segments   => (
      RakuAST::StrLiteral.new("B C"),
    )
  )
);

Takes a key and a value to add to the configuration. Value is expected to be either a string or a RakuAST object.