diff --git a/packages/core/src/agents/agent-tool.ts b/packages/core/src/agents/agent-tool.ts
index 2258bfb43a..8bbe654fd4 100644
--- a/packages/core/src/agents/agent-tool.ts
+++ b/packages/core/src/agents/agent-tool.ts
@@ -166,7 +166,7 @@ class DelegateInvocation extends BaseToolInvocation<
       );
     }
 
-    const useSession = this.context.config.isAgentSessionEnabled();
+    const useSession = this.context.config.isAgentSessionSubagentEnabled();
     const options = this.onAgentEvent
       ? { onAgentEvent: this.onAgentEvent }
       : undefined;