diff --git a/packages/server/src/server/agent/agent-manager.test.ts b/packages/server/src/server/agent/agent-manager.test.ts
index 221c928466..e4bc0eeda5 100644
--- a/packages/server/src/server/agent/agent-manager.test.ts
+++ b/packages/server/src/server/agent/agent-manager.test.ts
@@ -452,7 +452,7 @@ class TestAgentSession implements AgentSession {
 
   async respondToPermission(): Promise<void> {}
 
-  describePersistence() {
+  describePersistence(): AgentPersistenceHandle | null {
     return {
       provider: this.provider,
       sessionId: this.id,