# 0001 — Comparison stack: classical, label-free, CPU-first

Decision (2026-08-21): structural comparison uses graph edit distance
(edit script = the loss vector, mechanically), Weisfeiler-Leman
refinement and spectral signatures (label-free fingerprints), and
permutation/rewiring nulls. networkx/scipy scale; artifacts parse to
~5–50 node graphs. No GNNs, no vector DB, no graph DB at bootstrap.

The GPU is the measurement apparatus, not the math engine: local qwen
(frozen, reproducible, cheap at volume) + frontier models as a second
instrument family (§30); embeddings only as the baseline to beat (§88).
Disk is unconstrained → full generation contexts are archived verbatim
(§50 resolved by storage abundance).

Wiring discipline inherited from riverbed: models propose, deterministic
code adjudicates. The kernel computes no similarity (ADR-0000).

Reconsider when: artifacts stop fitting in small graphs; GED cost
sensitivity tests show hand-set costs dominate results; or an experiment
needs behavior (simulation) rather than structure.

Researcher input 2026-08-21: "the thing is sufficiently described...
4090 + effectively infinite disk; slow is acceptable." Bottleneck moved
from review to experiment design; design note 0000 status changed to
STANDING UNLESS OBJECTED.