diff --git a/packages/core/test/session-runner-tool-events.test.ts b/packages/core/test/session-runner-tool-events.test.ts
index 1bfbe20557..1cdc71788a 100644
--- a/packages/core/test/session-runner-tool-events.test.ts
+++ b/packages/core/test/session-runner-tool-events.test.ts
@@ -182,7 +182,7 @@ test("binary failure emits no success event", async () => {
 test("success event data can carry a provider-executed result", () => {
   const decoded = Schema.decodeUnknownSync(SessionEvent.Tool.Success.data)({
     sessionID,
-    messageID: SessionMessage.ID.create(),
+    assistantMessageID: SessionMessage.ID.create(),
     callID: "call-old",
     structured: { type: "media", mime: "image/png" },
     content: [{ type: "file", uri: `data:image/png;base64,${base64}`, mime: "image/png" }],