diff --git a/deploy/README.md b/deploy/README.md
index 5401247..1381864 100644
--- a/deploy/README.md
+++ b/deploy/README.md
@@ -114,9 +114,12 @@ semantic row.
 ## alert rules
 
 `prometheus/rules.yml` is the in-repo source for the Prometheus alert rules;
-the box's Prometheus reads its own copy from `/opt/stream-experiment/`, so a
-rule change here is not live until that copy is replaced and Prometheus
-reloaded. Validate with `promtool check rules deploy/prometheus/rules.yml`
+the box's Prometheus reads its own copy at `/opt/stream-experiment/rules.yml`
+(mounted to `/etc/prometheus/rules.yml`, listed under `rule_files` in
+`prometheus.yml`), so a rule change here is not live until that copy is
+replaced and Prometheus restarted (`docker compose up -d prometheus`; the
+container has no `--web.enable-lifecycle`, so there is no reload endpoint).
+Wired up 2026-08-29; before that the box had no rules loaded at all. Validate with `promtool check rules deploy/prometheus/rules.yml`
 (e.g. via `docker run --rm -v "$PWD/deploy/prometheus:/rules:ro" --entrypoint
 promtool prom/prometheus check rules /rules/rules.yml`). The rules have no
 notification route; they surface only in Prometheus/Grafana alert state.