diff --git a/src/agents/pi-embedded-runner/run.overflow-compaction.mocks.shared.ts b/src/agents/pi-embedded-runner/run.overflow-compaction.mocks.shared.ts
index dfc2bc0c961..5276bd1c0d6 100644
--- a/src/agents/pi-embedded-runner/run.overflow-compaction.mocks.shared.ts
+++ b/src/agents/pi-embedded-runner/run.overflow-compaction.mocks.shared.ts
@@ -210,12 +210,21 @@ vi.mock("../defaults.js", () => ({
 }));
 
 export const mockedCoerceToFailoverError = vi.fn();
-export const mockedDescribeFailoverError = vi.fn((err: unknown) => ({
-  message: err instanceof Error ? err.message : String(err),
-  reason: undefined,
-  status: undefined,
-  code: undefined,
-}));
+type MockFailoverErrorDescription = {
+  message: string;
+  reason: string | undefined;
+  status: number | undefined;
+  code: string | undefined;
+};
+
+export const mockedDescribeFailoverError = vi.fn(
+  (err: unknown): MockFailoverErrorDescription => ({
+    message: err instanceof Error ? err.message : String(err),
+    reason: undefined,
+    status: undefined,
+    code: undefined,
+  }),
+);
 export const mockedResolveFailoverStatus = vi.fn();
 
 vi.mock("../failover-error.js", () => ({
diff --git a/src/agents/pi-embedded-runner/run.overflow-compaction.test.ts b/src/agents/pi-embedded-runner/run.overflow-compaction.test.ts
index 8458e840e70..d18123a4ae2 100644
--- a/src/agents/pi-embedded-runner/run.overflow-compaction.test.ts
+++ b/src/agents/pi-embedded-runner/run.overflow-compaction.test.ts
@@ -301,7 +301,7 @@ describe("runEmbeddedPiAgent overflow compaction trigger routing", () => {
     await expect(
       runEmbeddedPiAgent({
         ...overflowBaseRunParams,
-        cfg: {
+        config: {
           agents: {
             defaults: {
               model: {