diff --git a/src/headless-events.ts b/src/headless-events.ts
index 8a64e96c0..4710db020 100644
--- a/src/headless-events.ts
+++ b/src/headless-events.ts
@@ -174,10 +174,13 @@ export function isMilestoneReadyNotification(
 ): boolean {
 	if (event.type !== "extension_ui_request" || event.method !== "notify")
 		return false;
-	// Structured: approval_request+blocking is the milestone-ready signal.
 	const meta = getEventMetadata(event);
-	if (meta?.kind === "approval_request" && meta.blocking === true) return true;
-	// Fallback: legacy text heuristics.
+	if (meta !== undefined) {
+		// Metadata present: it is the authoritative source. Do not fall back to
+		// text matching — the emitter declared the event kind explicitly.
+		return meta.kind === "approval_request" && meta.blocking === true;
+	}
+	// No metadata — fall back to legacy text heuristics.
 	return isMilestoneReadyText(String(event.message ?? ""));
 }