diff --git a/codex-rs/core/src/session/session.rs b/codex-rs/core/src/session/session.rs
index c944907274..5194f85186 100644
--- a/codex-rs/core/src/session/session.rs
+++ b/codex-rs/core/src/session/session.rs
@@ -351,10 +351,8 @@ impl SessionConfiguration {
         current_environments: &[TurnEnvironmentSelection],
     ) -> ConstraintResult<Self> {
         let mut next_configuration = self.clone();
-        let current_sandbox_policy = self.sandbox_policy(current_environments);
         let current_file_system_sandbox_policy =
             self.file_system_sandbox_policy(current_environments);
-        let current_network_sandbox_policy = self.network_sandbox_policy();
         let file_system_policy_has_rebindable_project_root_write =
             current_file_system_sandbox_policy
                 .entries
@@ -437,35 +435,37 @@ impl SessionConfiguration {
                         network_sandbox_policy,
                     ),
                 )?;
-        } else if cwd_changed
-            && file_system_policy_has_rebindable_project_root_write
-            && current_file_system_sandbox_policy.is_semantically_equivalent_to(
+        } else if cwd_changed && file_system_policy_has_rebindable_project_root_write {
+            // Compatibility projection can resolve filesystem paths. Only compute it
+            // when a cwd-bound legacy policy might need rebinding.
+            let current_sandbox_policy = self.sandbox_policy(current_environments);
+            if current_file_system_sandbox_policy.is_semantically_equivalent_to(
                 &FileSystemSandboxPolicy::from_legacy_sandbox_policy_preserving_deny_entries(
                     &current_sandbox_policy,
                     self.cwd(),
                     &current_file_system_sandbox_policy,
                 ),
                 self.cwd(),
-            )
-        {
-            // Preserve richer split policies across cwd-only updates; only
-            // rederive when the session is already using a structurally
-            // cwd-bound legacy bridge.
-            let file_system_sandbox_policy =
-                FileSystemSandboxPolicy::from_legacy_sandbox_policy_preserving_deny_entries(
-                    &current_sandbox_policy,
-                    next_configuration.cwd(),
-                    &current_file_system_sandbox_policy,
-                );
-            next_configuration
-                .permission_profile_state
-                .set_legacy_permission_profile(
-                    PermissionProfile::from_runtime_permissions_with_enforcement(
-                        SandboxEnforcement::from_legacy_sandbox_policy(&current_sandbox_policy),
-                        &file_system_sandbox_policy,
-                        current_network_sandbox_policy,
-                    ),
-                )?;
+            ) {
+                // Preserve richer split policies across cwd-only updates; only
+                // rederive when the session is already using a structurally
+                // cwd-bound legacy bridge.
+                let file_system_sandbox_policy =
+                    FileSystemSandboxPolicy::from_legacy_sandbox_policy_preserving_deny_entries(
+                        &current_sandbox_policy,
+                        next_configuration.cwd(),
+                        &current_file_system_sandbox_policy,
+                    );
+                next_configuration
+                    .permission_profile_state
+                    .set_legacy_permission_profile(
+                        PermissionProfile::from_runtime_permissions_with_enforcement(
+                            SandboxEnforcement::from_legacy_sandbox_policy(&current_sandbox_policy),
+                            &file_system_sandbox_policy,
+                            self.network_sandbox_policy(),
+                        ),
+                    )?;
+            }
         }
         if let Some(app_server_client_name) = updates.app_server_client_name.clone() {
             next_configuration.app_server_client_name = Some(app_server_client_name);
diff --git a/codex-rs/core/src/session/tests.rs b/codex-rs/core/src/session/tests.rs
index 95566b13a3..1637cb5d9b 100644
--- a/codex-rs/core/src/session/tests.rs
+++ b/codex-rs/core/src/session/tests.rs
@@ -5328,6 +5328,55 @@ async fn resolved_environments_for_configuration(
     (environment_manager, turn_environments.snapshot().await)
 }
 
+#[tokio::test]
+async fn session_configuration_apply_client_metadata_preserves_permissions() {
+    let mut configuration = make_session_configuration_for_tests().await;
+    let workspace = tempfile::tempdir().expect("create workspace");
+    let cwd = workspace.path().abs();
+    configuration.legacy_fallback_cwd = cwd.clone();
+    let permission_profile = PermissionProfile::from_runtime_permissions_with_enforcement(
+        SandboxEnforcement::Managed,
+        &FileSystemSandboxPolicy::restricted(vec![
+            FileSystemSandboxEntry::new(
+                FileSystemPath::Path {
+                    path: cwd.join("writable").into(),
+                },
+                FileSystemAccessMode::Write,
+            ),
+            FileSystemSandboxEntry::new(
+                FileSystemPath::Path {
+                    path: cwd.join("writable/private").into(),
+                },
+                FileSystemAccessMode::Deny,
+            ),
+        ]),
+        NetworkSandboxPolicy::Restricted,
+    );
+    configuration
+        .set_permission_profile_for_tests(permission_profile)
+        .expect("set custom permission profile");
+    let expected = configuration.thread_settings_snapshot(&[]);
+    let updated = configuration
+        .apply(
+            &SessionSettingsUpdate {
+                app_server_client_name: Some("codex-tui".to_string()),
+                app_server_client_version: Some("1.0.0".to_string()),
+                ..Default::default()
+            },
+            &[],
+        )
+        .expect("update client metadata");
+
+    assert_eq!(updated.thread_settings_snapshot(&[]), expected);
+    assert_eq!(
+        (
+            updated.app_server_client_name,
+            updated.app_server_client_version
+        ),
+        (Some("codex-tui".to_string()), Some("1.0.0".to_string())),
+    );
+}
+
 #[tokio::test]
 async fn session_configuration_apply_preserves_profile_file_system_policy_on_cwd_only_update() {
     let mut session_configuration = make_session_configuration_for_tests().await;