diff --git a/codex-rs/tui/src/app_server_session.rs b/codex-rs/tui/src/app_server_session.rs
index a21b4c099d..fb8f80267f 100644
--- a/codex-rs/tui/src/app_server_session.rs
+++ b/codex-rs/tui/src/app_server_session.rs
@@ -1118,7 +1118,10 @@ fn sandbox_mode_from_permission_profile(
                     .network_sandbox_policy()
                     .is_enabled()
                     .then_some(codex_app_server_protocol::SandboxMode::DangerFullAccess)
-            } else if file_system_policy.can_write_path_with_cwd(cwd, cwd) {
+            } else if !file_system_policy
+                .get_writable_roots_with_cwd(cwd)
+                .is_empty()
+            {
                 Some(codex_app_server_protocol::SandboxMode::WorkspaceWrite)
             } else {
                 Some(codex_app_server_protocol::SandboxMode::ReadOnly)
@@ -1508,6 +1511,12 @@ mod tests {
     use codex_app_server_protocol::ThreadStatus;
     use codex_app_server_protocol::Turn;
     use codex_app_server_protocol::TurnStatus;
+    use codex_protocol::models::ManagedFileSystemPermissions;
+    use codex_protocol::permissions::FileSystemAccessMode;
+    use codex_protocol::permissions::FileSystemPath;
+    use codex_protocol::permissions::FileSystemSandboxEntry;
+    use codex_protocol::permissions::FileSystemSpecialPath;
+    use codex_protocol::permissions::NetworkSandboxPolicy;
     use codex_utils_absolute_path::test_support::PathBufExt;
     use codex_utils_absolute_path::test_support::test_path_buf;
     use pretty_assertions::assert_eq;
@@ -1600,6 +1609,35 @@ mod tests {
         assert_eq!(fork.permission_profile, None);
     }
 
+    #[test]
+    fn sandbox_mode_preserves_non_cwd_write_roots_for_remote_sessions() {
+        let cwd = test_path_buf("/workspace/project").abs();
+        let extra_root = test_path_buf("/workspace/cache").abs();
+        let permission_profile = PermissionProfile::Managed {
+            file_system: ManagedFileSystemPermissions::Restricted {
+                entries: vec![
+                    FileSystemSandboxEntry {
+                        path: FileSystemPath::Special {
+                            value: FileSystemSpecialPath::Root,
+                        },
+                        access: FileSystemAccessMode::Read,
+                    },
+                    FileSystemSandboxEntry {
+                        path: FileSystemPath::Path { path: extra_root },
+                        access: FileSystemAccessMode::Write,
+                    },
+                ],
+                glob_scan_max_depth: None,
+            },
+            network: NetworkSandboxPolicy::Restricted,
+        };
+
+        assert_eq!(
+            sandbox_mode_from_permission_profile(&permission_profile, cwd.as_path()),
+            Some(codex_app_server_protocol::SandboxMode::WorkspaceWrite)
+        );
+    }
+
     #[tokio::test]
     async fn thread_lifecycle_params_forward_explicit_remote_cwd_override_for_remote_sessions() {
         let temp_dir = tempfile::tempdir().expect("tempdir");