Typically a shop drawing is not included in the construction contract because it is sent by a particular shop in response to the designer’s construction drawing describing intent. It may help to think of a shop drawing as a ‘specific response’ and the design intent drawing as a 'general call". Metaphorically, I might ‘call’ for a mustard for my sandwich, but before accepting the sandwich I might require the server to describe what brand of mustard and how much and where it will be placed on my bread before accepting it for consumption. If the shop drawing (waiter’s description of what the kitchen will provide) ‘response’ is adequate, I might accept it on behalf my design for a good sandwich! The mustard requirements are best identified when reviewing the menu and placing the order (bidding), and acceptance of the Dijon applied liberally on side of the toast under lettuce after the order is placed. Please let me know if this analogy makes sense for you or if you hunger for more information.