Abstract: Disclosed herein are methods and systems for user-interface-assisted composition construction. In an embodiment, a plurality of input fields, each having an argument-element type, is presented via a client-side user interface, initially arranged according to a predefined sequence. Textual inputs are received via the input fields, and corresponding argument-building-block elements are responsively presented via the client-side user interface according to a current arrangement on the client-side user interface of the input fields. Each presented argument-building-block element has the same argument-element type and the received textual input of the corresponding user-interface input field.