diff --git a/src/auto-reply/reply.ts b/src/auto-reply/reply.ts
index b1ab4b34e..3670118ae 100644
--- a/src/auto-reply/reply.ts
+++ b/src/auto-reply/reply.ts
@@ -767,7 +767,9 @@ export async function getReplyFromConfig(
       }
       if (sessionCfg && sessionStore && sessionKey) {
         const returnedSessionId = meta.agentMeta?.sessionId;
-        if (returnedSessionId && returnedSessionId !== sessionId) {
+        // TODO: remove once pi-mono persists stable session ids for custom --session paths.
+        const allowMetaSessionId = false;
+        if (allowMetaSessionId && returnedSessionId && returnedSessionId !== sessionId) {
           const entry = sessionEntry ??
             sessionStore[sessionKey] ?? {
               sessionId: returnedSessionId,