diff --git a/wechat-mp.mjs b/wechat-mp.mjs
index 3e35a90..16ef1e2 100644
--- a/wechat-mp.mjs
+++ b/wechat-mp.mjs
@@ -1701,6 +1701,9 @@ export function createWechatMpService({
     // `/agent/start` already persists the owning user and goosed node via the
     // portal proxy. Re-registering here without the node can overwrite the
     // correct mapping back to node 0 in multi-goosed production.
+    if (!startAgentSession && typeof userAuth.registerAgentSession === 'function') {
+      await userAuth.registerAgentSession(userId, sessionId);
+    }
     await reconcileAgentSession(
       (pathname, init) => fetchForSession(sessionId, pathname, init),
       sessionId,