diff --git a/codex-rs/core/tests/suite/tool_harness.rs b/codex-rs/core/tests/suite/tool_harness.rs
index 5fc6c40577..a31c1355aa 100644
--- a/codex-rs/core/tests/suite/tool_harness.rs
+++ b/codex-rs/core/tests/suite/tool_harness.rs
@@ -515,7 +515,10 @@ async fn apply_patch_multi_environment_uses_remote_executor() -> anyhow::Result<
         !function_local_path.exists(),
         "function-call targeted patch should not write locally"
     );
-    let function_remote_contents = test.fs().read_file(&function_remote_path, None).await?;
+    let function_remote_contents = test
+        .fs()
+        .read_file(&function_remote_path, /*sandbox*/ None)
+        .await?;
     assert_eq!(
         String::from_utf8(function_remote_contents)?,
         "patched via remote function\n"
@@ -571,7 +574,10 @@ async fn apply_patch_multi_environment_uses_remote_executor() -> anyhow::Result<
         !freeform_local_path.exists(),
         "freeform targeted patch should not write locally"
     );
-    let freeform_remote_contents = test.fs().read_file(&freeform_remote_path, None).await?;
+    let freeform_remote_contents = test
+        .fs()
+        .read_file(&freeform_remote_path, /*sandbox*/ None)
+        .await?;
     assert_eq!(
         String::from_utf8(freeform_remote_contents)?,
         "patched via remote freeform\n"