diff --git a/src/agents/pi-embedded-runner.openai-tool-id-preservation.test.ts b/src/agents/pi-embedded-runner.openai-tool-id-preservation.test.ts
index b66ab02d404..04445c26590 100644
--- a/src/agents/pi-embedded-runner.openai-tool-id-preservation.test.ts
+++ b/src/agents/pi-embedded-runner.openai-tool-id-preservation.test.ts
@@ -63,12 +63,12 @@ describe("sanitizeSessionHistory openai tool id preservation", () => {
     {
       name: "strips fc ids when replayable reasoning metadata is missing",
       withReasoning: false,
-      expectedToolId: "call123",
+      expectedToolId: "call_123",
     },
     {
       name: "keeps canonical call_id|fc_id pairings when replayable reasoning is present",
       withReasoning: true,
-      expectedToolId: "call123fc123",
+      expectedToolId: "call_123|fc_123",
     },
   ])("$name", async ({ withReasoning, expectedToolId }) => {
     const result = await sanitizeSessionHistory({
@@ -121,7 +121,7 @@ describe("sanitizeSessionHistory openai tool id preservation", () => {
       isError?: boolean;
     };
     expect(toolResult.role).toBe("toolResult");
-    expect(toolResult.toolCallId).toBe("call123");
+    expect(toolResult.toolCallId).toBe("call_123");
     expect(toolResult.content?.[0]?.text).toBe("ok");
     expect(toolResult.isError).toBe(false);