I don't know if we do the same (I'm on AQA doing 2N - Russia 1917-29 for AS). My source question's structure follow like this:
No intro
Source A
Content paragraph - picking out content and linking it to contextual knowledge in relation to the question
Provenance paragraph - who produced the source, why, when etc. and the significance of this in relation to contextual knowledge and how valuable it is based on these things.
My teacher tells me to give a large amount of focus on provenance.
Source B
Same structure as Source A
Conclusion
Which source is most valuable taking into account provenance and content - can be one of them, or both, or neither and then explain why
Hope this helps!