diff --git a/src/auto-reply/reply/session-transcript-replay.test.ts b/src/auto-reply/reply/session-transcript-replay.test.ts
index 34961b862fd..581d777efd8 100644
--- a/src/auto-reply/reply/session-transcript-replay.test.ts
+++ b/src/auto-reply/reply/session-transcript-replay.test.ts
@@ -9,6 +9,27 @@ import {
 
 const j = (obj: unknown): string => `${JSON.stringify(obj)}\n`;
 
+type ReplayRecord = {
+  type?: string;
+  id?: string;
+  message?: {
+    role?: string;
+    content?: string;
+  };
+};
+
+async function readJsonlRecords(filePath: string): Promise<ReplayRecord[]> {
+  const records: ReplayRecord[] = [];
+  const raw = await fs.readFile(filePath, "utf8");
+  for (const line of raw.split(/\r?\n/)) {
+    if (line.trim().length === 0) {
+      continue;
+    }
+    records.push(JSON.parse(line) as ReplayRecord);
+  }
+  return records;
+}
+
 describe("replayRecentUserAssistantMessages", () => {
   let root = "";
   beforeEach(async () => {
@@ -37,14 +58,11 @@ describe("replayRecentUserAssistantMessages", () => {
     await fs.writeFile(source, lines.join(""), "utf8");
 
     expect(await call(source, target)).toBe(DEFAULT_REPLAY_MAX_MESSAGES);
-    const records = (await fs.readFile(target, "utf8"))
-      .split(/\r?\n/)
-      .filter((line) => line.trim().length > 0)
-      .map((line) => JSON.parse(line));
+    const records = await readJsonlRecords(target);
     expect(records[0]).toMatchObject({ type: "session", id: "new-session" });
     expect(records).toHaveLength(1 + DEFAULT_REPLAY_MAX_MESSAGES);
     for (const r of records.slice(1)) {
-      expect(["user", "assistant"]).toContain(r.message.role);
+      expect(["user", "assistant"]).toContain(r.message?.role);
     }
     expect(await call(path.join(root, "missing.jsonl"), path.join(root, "out.jsonl"))).toBe(0);
 
@@ -69,13 +87,10 @@ describe("replayRecentUserAssistantMessages", () => {
     await fs.writeFile(source, lines.join(""), "utf8");
 
     expect(await call(source, target)).toBe(DEFAULT_REPLAY_MAX_MESSAGES - 1);
-    const records = (await fs.readFile(target, "utf8"))
-      .split(/\r?\n/)
-      .filter((line) => line.trim().length > 0)
-      .map((line) => JSON.parse(line));
+    const records = await readJsonlRecords(target);
     expect(records.reduce((count, r) => count + (r.type === "session" ? 1 : 0), 0)).toBe(1);
     expect(records[0]).toMatchObject({ id: "existing" });
-    expect(records[1].message.role).toBe("user");
+    expect(records[1].message?.role).toBe("user");
   });
 
   it("coalesces same-role runs so replayed records strictly alternate", async () => {
@@ -95,17 +110,14 @@ describe("replayRecentUserAssistantMessages", () => {
     );
 
     expect(await call(source, target)).toBe(4);
-    const records = (await fs.readFile(target, "utf8"))
-      .split(/\r?\n/)
-      .filter((line) => line.trim().length > 0)
-      .map((line) => JSON.parse(line));
-    expect(records.slice(1).map((r) => r.message.role)).toEqual([
+    const records = await readJsonlRecords(target);
+    expect(records.slice(1).map((r) => r.message?.role)).toEqual([
       "user",
       "assistant",
       "user",
       "assistant",
     ]);
-    expect(records.slice(1).map((r) => r.message.content)).toEqual([
+    expect(records.slice(1).map((r) => r.message?.content)).toEqual([
       "latest user",
       "latest assistant",
       "follow-up",