Putting the evidence in the prompt did not fix a small reader. In the preprint, two thirds of the errors on the development split happened with the gold session already loaded. 86% on LoCoMo using the Mem0-paper judge (2-conversation sample) is a separate measured figure. It is not a comparison with Mem0.
I kept seeing memory demos reported as one accuracy number. That hides whether the retriever failed or the reader failed. The preprint Evidence in Context Is Not Enough splits those cases for a small reader. It is not peer reviewed.
The evidence was often already there
On the development split, two thirds of the errors happened with the gold evidence session already loaded. The answers were not cut off for length. The common misses were abstaining while the fact was present, and picking a near-duplicate from another session. Several camping trips, several paintings. The sibling looks plausible.
What I tried that did not hold
Fine-tuning, asking the model to quote first, a self-check retry, an instruction to stop abstaining, rewritten notes, and retrieval re-scoring did not beat the baseline under gates I wrote before measuring. A second retrieval pass looked better on the development split and did not hold on other conversations.
The change that held was in the notes. Resolving “yesterday” to a calendar date, and keeping the original wording, improved a held-out sample before I froze the baseline. Changing the reader did less than changing what the note said.
Read the number as noisy
86% on LoCoMo using the Mem0-paper judge (2-conversation sample) is a measured figure from that setup. It is not the paper’s strict-judge split, and it is not a claim that Archilas beats Mem0. One added prompt line changed 20 of 233 answers. I treat a swing of about five questions as noise. These numbers are not comparable to published LoCoMo scores that use different readers and judges.
The product side of this is simpler: keep the date on the note, and mark the older decision when a newer one replaces it. That write-up is Decisions change.