recall-strategylisted
Install: claude install-skill Ybx-jp/thalamus
# Recall Strategy — Spend Context Where It Earns
Every token a retrieval renders rides along in **every later call of this
session**. The eval loop prices this: **33.8% of injected
retrieval tokens are judged unused, 95% CI [27.2, 40.5]** with sessions as the
sampling unit — and once corrected for a judge that calls ~59% of *unrelated*
tokens used, only about **17.5% of injected tokens are demonstrably earned**.
The waste is fan-out: worst recalls returned 50–81 nodes at 28–40% use, best
returned 3–5 at 66–80% (the fan-out counts hold; the used-rates measured
alongside them were withdrawn). The reader now enforces a match floor and a
detail cap, but query shape is still yours. Cost-tiered retrieval is the field's
answer too (BudgetMem, arXiv 2602.06025): pay for depth only where the query
earns it.
## The ladder — cheapest rung that answers
**Query before you build.** Before designing a new node type, a new precomputed
layer, or a new summary artifact, ask whether an existing traversal already
answers it. The schema expresses more than most designs assume: `Exchange` holds
the question its citation edges answered, `Trace -RETURNS-> {used}` holds
retrieval utility, `DERIVED_FROM` reaches retained bytes. Records the system
already writes are usually *better* evidence than anything precomputed, because
they capture what was actually used rather than what someone anticipated — a
whole contribution-summary layer was withdrawn once someone ran the traversal
that already answered