Paper 5 · Question 47

A: A rolling window drops the isolation discussion once it ages out, which is most of three months.

B: A running summary can say the theme came up and lose the actual conclusion the user is asking for.

C: Semantic search over conversation history is the only approach that scales to three months of discussion while being able to surface specific relevant exchanges on demand. Rolling window (A) would discard most of the history. Progressive summarization (B) compresses discussions into abstractions that lose the specific conclusions users are asking about. XML tags (D) require restructuring all past content and don't solve the retrieval problem at this scale.

D: Tags help only if every past conclusion was marked at the time. They do not retrieve an old exchange, and they do not shrink 85K tokens.