diff --git a/extensions/discord/src/monitor/thread-title.generate.test.ts b/extensions/discord/src/monitor/thread-title.generate.test.ts
index 396b9c28166..620009eead1 100644
--- a/extensions/discord/src/monitor/thread-title.generate.test.ts
+++ b/extensions/discord/src/monitor/thread-title.generate.test.ts
@@ -11,6 +11,16 @@ const extractAssistantTextMock = vi.fn<typeof agentRuntimeModule.extractAssistan
 
 let generateThreadTitle: typeof import("./thread-title.js").generateThreadTitle;
 
+function firstCompletionArgs(): Parameters<
+  typeof agentRuntimeModule.completeWithPreparedSimpleCompletionModel
+>[0] {
+  const firstCall = completeWithPreparedSimpleCompletionModelMock.mock.calls.at(0);
+  if (!firstCall) {
+    throw new Error("expected completion call");
+  }
+  return firstCall[0];
+}
+
 beforeAll(async () => {
   ({ generateThreadTitle } = await import("./thread-title.js"));
 });
@@ -162,10 +172,7 @@ describe("generateThreadTitle", () => {
 
     expect(result).toBe("Generated title");
     expect(completeWithPreparedSimpleCompletionModelMock).toHaveBeenCalledTimes(1);
-    const completionArgs = completeWithPreparedSimpleCompletionModelMock.mock.calls[0]?.[0];
-    if (!completionArgs) {
-      throw new Error("expected completion call");
-    }
+    const completionArgs = firstCompletionArgs();
     expect(completionArgs.context).toEqual({
       systemPrompt:
         "Generate a concise Discord thread title (3-6 words). Return only the title. Use channel context when provided and avoid redundant channel-name words unless needed for clarity.",