diff --git a/run/critic.go b/run/critic.go
index 5b7d2a3..bf0ff7b 100644
--- a/run/critic.go
+++ b/run/critic.go
@@ -75,6 +75,13 @@ func (b *criticBinding) recordStep(iter int) {
 	}
 }
 
+// recordToolStart forwards a tool call to the critic. NOTE: majordomo's step
+// observer only fires AFTER an iteration completes, so this currently lands
+// post-tool, not at dispatch — the activity clock is refreshed once per
+// iteration, not mid-tool. A single very long tool call (e.g. a 30-min render)
+// therefore won't refresh the clock until it returns; a host that runs such
+// tools should feed interim progress to its Critic (mort's InstallProgressBridge
+// pattern). A true pre-dispatch refresh needs a majordomo hook (follow-up).
 func (b *criticBinding) recordToolStart(name, args string) {
 	if b != nil {
 		b.h.RecordToolStart(name, args)