When describing the document, is it required to describe the entire document, or can I only describe the part of the document that is relevant to the argument that I am going to make?
Describing the entirety of the document will most likely take too long and in my humble opinion wouldn’t achieve what the point wants from an answer. The points for using the documents are in relation to your argument.
Use the evidence to prove your thesis. Most CB docs will be clean and clear cut. However, some docs can prove more than one valid points and yes can counteract themselves. CB loves when students use the same doc twice. However, you should still plan on using either 2 or 4 unique docs to earn the rubric points.