diff --git a/03-DESIGN/01-to-be/47-milestones/G-20-lead-answers.md b/03-DESIGN/01-to-be/47-milestones/G-20-lead-answers.md
index c8f97d42..37135cfa 100644
--- a/03-DESIGN/01-to-be/47-milestones/G-20-lead-answers.md
+++ b/03-DESIGN/01-to-be/47-milestones/G-20-lead-answers.md
@@ -110,3 +110,7 @@ names the principle that settles it, and is cited as "design 47 G A-n".
   `views.Reader` holding the module's writer and adopted, as A-26. A single ask that is no follower (mesh-build-go's
   manifest ask, the tool runner's ask) writes and clears its `first-view-unanswered` finding itself through
   `Writer.Write` and `Writer.Clear` with the contract's `Finding`; mesh-sdk exports no helper for it.
+- **A-29** (§686, A-3; principle 7, shared code lives in mesh-sdk) A part whose findings are raised as they happen, not
+  judged afresh, uses one mesh-sdk form of the writer that observes from its own state: it seeds what it holds from the
+  state's keys before it starts, keeps them under its own lock, and its `Observe` answers them, so no part writes that
+  adapter (the watchman's copy moves there; the assigner, builder and indexer use it).