Usage frequency
A retrieval-priority input tracking how often a memory has been retrieved in recent sessions. Combined with reinforcement signal and goal relevance to compute retrieval priority. High usage frequency partially suppresses the novelty bonus to prevent frequently-retrieved memories from accumulating an additional novelty credit.
Usage frequency is tracked per memory and used in two distinct ways in the retrieval pipeline. First, it contributes positively to retrieval priority (weighted at 15%): memories that are retrieved frequently prove their usefulness repeatedly and deserve to remain accessible. Second, it suppresses the novelty bonus: the novelty scoring function computes a combined novelty as 70% raw novelty plus 30% inverse usage frequency. This prevents a frequently-retrieved memory from receiving a novelty credit even when its raw novelty score is high - ensuring that the novelty channel rewards genuinely new or underexplored memories rather than just ones that happen to score high on the raw novelty formula. This interaction is by design: usage frequency and novelty are complementary signals that together prevent attentional fixation on the same high-priority memories while still allowing heavily-used memories to maintain strong retrieval priority.