diff --git a/test/scripts/test-parallel.test.ts b/test/scripts/test-parallel.test.ts
index bbf7d8b202c..d97080171bc 100644
--- a/test/scripts/test-parallel.test.ts
+++ b/test/scripts/test-parallel.test.ts
@@ -88,6 +88,7 @@ function runPlannerPlan(args: string[], envOverrides: NodeJS.ProcessEnv = {}): s
     cwd: REPO_ROOT,
     env: createPlannerEnv(envOverrides),
     encoding: "utf8",
+    stdio: ["pipe", "pipe", "pipe"],
   });
 }
 
diff --git a/test/scripts/test-planner.executor-fallback.test.ts b/test/scripts/test-planner.executor-fallback.test.ts
index 150f0c0be29..7f4e5a71f9a 100644
--- a/test/scripts/test-planner.executor-fallback.test.ts
+++ b/test/scripts/test-planner.executor-fallback.test.ts
@@ -1,8 +1,15 @@
 import { EventEmitter } from "node:events";
 import { PassThrough } from "node:stream";
-import { afterEach, describe, expect, it, vi } from "vitest";
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 import { importFreshModule } from "../helpers/import-fresh.js";
 
+beforeEach(() => {
+  vi.spyOn(console, "log").mockImplementation(() => {});
+  vi.spyOn(console, "error").mockImplementation(() => {});
+  vi.spyOn(process.stdout, "write").mockImplementation(() => true);
+  vi.spyOn(process.stderr, "write").mockImplementation(() => true);
+});
+
 afterEach(() => {
   vi.useRealTimers();
   vi.restoreAllMocks();