diff --git a/docs/agents/MERGE-STATE.md b/docs/agents/MERGE-STATE.md
index 230d6d97..b2ef0670 100644
--- a/docs/agents/MERGE-STATE.md
+++ b/docs/agents/MERGE-STATE.md
@@ -6,11 +6,26 @@ measuring it. Measured 2026-08-31:
 
 | branch | ahead of `main` | behind | `main` an ancestor? | files |
 |---|---|---|---|---|
-| `auto/build-ordinal-audit` (decoder) | **328** | **0** | **yes** — fast-forward | 327 |
+| `auto/build-ordinal-audit` (decoder) | **328**+ | **0** | **yes** — fast-forward | 327 |
 | `auto/port-p6-audio` (port) | **257** | **0** | **yes** — fast-forward | 58 |
 
 ✅ **Each is individually a fast-forward with nothing to resolve.**
 
+⚠️ **The counts go stale by construction — every commit on either branch raises
+them.** `sylpheed-port` re-derived this the same day and read **329** for the
+decoder branch, because a commit landed between the measurement and the check.
+**The counts are not the claim.** What does not move with the count is: `main` is
+an ancestor of both, the two change sets touch **zero files in common**, and the
+dry-run merge is clean. Re-derive with:
+
+```
+git rev-list --count origin/main..<branch>
+git merge-base --is-ancestor origin/main <branch>
+comm -12 <(git diff --name-only $(git merge-base A B)..A | sort) \
+         <(git diff --name-only $(git merge-base A B)..B | sort)
+git merge-tree --write-tree A B        # read-only
+```
+
 ✅ **And they do not conflict with each other.** From their merge base (`1b1a4df`,
 2026-08-29):