diff --git a/docs/design/INDEX.md b/docs/design/INDEX.md
index d2e6ab4..633ea62 100644
--- a/docs/design/INDEX.md
+++ b/docs/design/INDEX.md
@@ -1996,7 +1996,17 @@ note; the `aura new` scaffolder followed in cycle 0103 — one command emits a
 buildable project whose blueprint runs through the merged vocabulary); of the
 two layers this paragraph used to name as sequencing-coupled, what remains
 open is the **composable-orchestration** thread (#109): topology-as-data is
-the substrate it stands on.
+the substrate it stands on. **Canonical project shape (#181, resolved
+2026-07-02):** the `aura new` templates (`scaffold.rs`) are the canonical
+authoring shape and evolve with the engine; the cycle-0102 `demo-project`
+fixture is an intentionally frozen known-good twin for the load-boundary
+tests. The two are deliberately **not** lockstep-guarded: no consumer requires
+them to match, each is e2e-guarded on its fitness for purpose (build →
+descriptor load → charter check → deterministic run — blueprint *wiring*
+content is pinned in neither, stated honestly), and an equality guard would
+convert every deliberate template improvement into forced churn of the frozen
+fixture — the same cross-purpose coupling that rules out regenerating the
+fixture from the scaffolder.
 
 **Op-script grammar (`aura graph build`, the #157 wire surface).** The construction
 op-script is a JSON **array of ops**, each object internally tagged by `"op"`,