diff --git a/codex-rs/tui/src/app/tests.rs b/codex-rs/tui/src/app/tests.rs
index 67dfa50da5..17953d538f 100644
--- a/codex-rs/tui/src/app/tests.rs
+++ b/codex-rs/tui/src/app/tests.rs
@@ -2211,7 +2211,6 @@ async fn inactive_thread_approval_bubbles_into_active_view() -> Result<()> {
             /*capacity*/ 1,
             ThreadSessionState {
                 approval_policy: AskForApproval::OnRequest,
-                sandbox_policy: SandboxPolicy::new_workspace_write_policy(),
                 permission_profile: PermissionProfile::workspace_write(),
                 rollout_path: Some(test_path_buf("/tmp/agent-rollout.jsonl")),
                 ..test_thread_session(agent_thread_id, test_path_buf("/tmp/agent"))
@@ -2371,7 +2370,6 @@ async fn side_defers_subagent_approval_overlay_until_side_exits() -> Result<()>
             /*capacity*/ 4,
             ThreadSessionState {
                 approval_policy: AskForApproval::OnRequest,
-                sandbox_policy: SandboxPolicy::new_workspace_write_policy(),
                 permission_profile: PermissionProfile::workspace_write(),
                 rollout_path: Some(test_path_buf("/tmp/agent-rollout.jsonl")),
                 ..test_thread_session(agent_thread_id, test_path_buf("/tmp/agent"))
@@ -2663,7 +2661,6 @@ async fn inactive_thread_approval_badge_clears_after_turn_completion_notificatio
             /*capacity*/ 4,
             ThreadSessionState {
                 approval_policy: AskForApproval::OnRequest,
-                sandbox_policy: SandboxPolicy::new_workspace_write_policy(),
                 permission_profile: PermissionProfile::workspace_write(),
                 rollout_path: Some(test_path_buf("/tmp/agent-rollout.jsonl")),
                 ..test_thread_session(agent_thread_id, test_path_buf("/tmp/agent"))
@@ -2717,7 +2714,6 @@ async fn inactive_thread_started_notification_initializes_replay_session() -> Re
         ThreadId::from_string("00000000-0000-0000-0000-000000000202").expect("valid thread");
     let primary_session = ThreadSessionState {
         approval_policy: AskForApproval::OnRequest,
-        sandbox_policy: SandboxPolicy::new_workspace_write_policy(),
         permission_profile: PermissionProfile::workspace_write(),
         ..test_thread_session(main_thread_id, test_path_buf("/tmp/main"))
     };
@@ -2742,7 +2738,7 @@ async fn inactive_thread_started_notification_initializes_replay_session() -> Re
         current_date: None,
         timezone: None,
         approval_policy: primary_session.approval_policy,
-        sandbox_policy: primary_session.sandbox_policy.clone(),
+        sandbox_policy: SandboxPolicy::new_workspace_write_policy(),
         permission_profile: None,
         network: None,
         file_system_sandbox_policy: None,
@@ -2830,7 +2826,6 @@ async fn inactive_thread_started_notification_preserves_primary_model_when_path_
         ThreadId::from_string("00000000-0000-0000-0000-000000000302").expect("valid thread");
     let primary_session = ThreadSessionState {
         approval_policy: AskForApproval::OnRequest,
-        sandbox_policy: SandboxPolicy::new_workspace_write_policy(),
         permission_profile: PermissionProfile::workspace_write(),
         ..test_thread_session(main_thread_id, test_path_buf("/tmp/main"))
     };
@@ -2899,7 +2894,6 @@ async fn thread_read_session_state_does_not_reuse_primary_permission_profile() {
         ThreadId::from_string("00000000-0000-0000-0000-000000000402").expect("valid thread");
     let primary_session = ThreadSessionState {
         approval_policy: AskForApproval::OnRequest,
-        sandbox_policy: SandboxPolicy::new_workspace_write_policy(),
         permission_profile: PermissionProfile::workspace_write(),
         ..test_thread_session(main_thread_id, test_path_buf("/tmp/main"))
     };
@@ -3805,7 +3799,6 @@ fn test_thread_session(thread_id: ThreadId, cwd: PathBuf) -> ThreadSessionState
         service_tier: None,
         approval_policy: AskForApproval::Never,
         approvals_reviewer: ApprovalsReviewer::User,
-        sandbox_policy: SandboxPolicy::new_read_only_policy(),
         permission_profile: PermissionProfile::read_only(),
         cwd: cwd.abs(),
         instruction_source_paths: Vec::new(),
diff --git a/codex-rs/tui/src/app/thread_events.rs b/codex-rs/tui/src/app/thread_events.rs
index d73c39dfea..10fc370f58 100644
--- a/codex-rs/tui/src/app/thread_events.rs
+++ b/codex-rs/tui/src/app/thread_events.rs
@@ -335,7 +335,6 @@ mod tests {
     use codex_config::types::ApprovalsReviewer;
     use codex_protocol::models::PermissionProfile;
     use codex_protocol::protocol::AskForApproval;
-    use codex_protocol::protocol::SandboxPolicy;
     use pretty_assertions::assert_eq;
     use std::path::PathBuf;
 
@@ -350,7 +349,6 @@ mod tests {
             service_tier: None,
             approval_policy: AskForApproval::Never,
             approvals_reviewer: ApprovalsReviewer::User,
-            sandbox_policy: SandboxPolicy::new_read_only_policy(),
             permission_profile: PermissionProfile::read_only(),
             cwd: cwd.abs(),
             instruction_source_paths: Vec::new(),
diff --git a/codex-rs/tui/src/app/thread_session_state.rs b/codex-rs/tui/src/app/thread_session_state.rs
index 9a30101fc2..71b847d819 100644
--- a/codex-rs/tui/src/app/thread_session_state.rs
+++ b/codex-rs/tui/src/app/thread_session_state.rs
@@ -14,10 +14,6 @@ impl App {
 
         let approval_policy = self.config.permissions.approval_policy.value();
         let approvals_reviewer = self.config.approvals_reviewer;
-        let sandbox_policy = self
-            .config
-            .permissions
-            .legacy_sandbox_policy(self.config.cwd.as_path());
         let permission_profile = self
             .chat_widget
             .config_ref()
@@ -26,7 +22,6 @@ impl App {
         let update_session = |session: &mut ThreadSessionState| {
             session.approval_policy = approval_policy;
             session.approvals_reviewer = approvals_reviewer;
-            session.sandbox_policy = sandbox_policy.clone();
             session.permission_profile = permission_profile.clone();
         };
 
@@ -49,7 +44,6 @@ impl App {
         thread_id: ThreadId,
         thread: &Thread,
     ) -> ThreadSessionState {
-        let sandbox_policy = self.active_legacy_sandbox_policy_for_cwd(thread.cwd.as_path());
         let mut session = self
             .primary_session_configured
             .clone()
@@ -63,7 +57,6 @@ impl App {
                 service_tier: self.chat_widget.current_service_tier(),
                 approval_policy: self.config.permissions.approval_policy.value(),
                 approvals_reviewer: self.config.approvals_reviewer,
-                sandbox_policy,
                 permission_profile: self
                     .active_legacy_permission_profile_for_cwd(thread.cwd.as_path()),
                 cwd: thread.cwd.clone(),
@@ -78,7 +71,6 @@ impl App {
         session.thread_name = thread.name.clone();
         session.model_provider_id = thread.model_provider.clone();
         session.cwd = thread.cwd.clone();
-        session.sandbox_policy = self.active_legacy_sandbox_policy_for_cwd(thread.cwd.as_path());
         session.permission_profile =
             self.active_legacy_permission_profile_for_cwd(thread.cwd.as_path());
         session.instruction_source_paths = Vec::new();
@@ -140,7 +132,6 @@ mod tests {
             service_tier: None,
             approval_policy: AskForApproval::Never,
             approvals_reviewer: ApprovalsReviewer::User,
-            sandbox_policy: SandboxPolicy::new_read_only_policy(),
             permission_profile: PermissionProfile::read_only(),
             cwd: cwd.abs(),
             instruction_source_paths: Vec::new(),
@@ -162,7 +153,7 @@ mod tests {
         let main_session = test_thread_session(main_thread_id, test_path_buf("/tmp/main"));
         let side_session = ThreadSessionState {
             approval_policy: AskForApproval::OnRequest,
-            sandbox_policy: SandboxPolicy::new_workspace_write_policy(),
+            permission_profile: PermissionProfile::workspace_write(),
             ..test_thread_session(side_thread_id, test_path_buf("/tmp/side"))
         };
 
@@ -214,7 +205,6 @@ mod tests {
         let expected_main_session = ThreadSessionState {
             approval_policy: AskForApproval::OnRequest,
             approvals_reviewer: ApprovalsReviewer::AutoReview,
-            sandbox_policy: expected_sandbox_policy,
             permission_profile: expected_permission_profile,
             ..main_session
         };
@@ -317,7 +307,7 @@ mod tests {
         let read_thread_id =
             ThreadId::from_string("00000000-0000-0000-0000-000000000405").expect("valid thread");
         let primary_session = ThreadSessionState {
-            permission_profile: PermissionProfile::legacy_workspace_write_template(),
+            permission_profile: PermissionProfile::workspace_write(),
             ..test_thread_session(primary_thread_id, test_path_buf("/tmp/primary"))
         };
         let read_thread = Thread {
@@ -356,7 +346,6 @@ mod tests {
             &expected_sandbox_policy,
             read_thread.cwd.as_path(),
         );
-        assert_eq!(session.sandbox_policy, expected_sandbox_policy);
         assert_eq!(session.permission_profile, expected_permission_profile);
         assert_ne!(
             session.permission_profile,
diff --git a/codex-rs/tui/src/app_server_session.rs b/codex-rs/tui/src/app_server_session.rs
index 5a33896dd3..0d38449db9 100644
--- a/codex-rs/tui/src/app_server_session.rs
+++ b/codex-rs/tui/src/app_server_session.rs
@@ -156,9 +156,6 @@ pub(crate) struct ThreadSessionState {
     pub(crate) service_tier: Option<codex_protocol::config_types::ServiceTier>,
     pub(crate) approval_policy: AskForApproval,
     pub(crate) approvals_reviewer: codex_protocol::config_types::ApprovalsReviewer,
-    /// Legacy sandbox projection kept only for compatibility fields that have
-    /// not migrated to `PermissionProfile` yet.
-    pub(crate) sandbox_policy: SandboxPolicy,
     /// Canonical active permissions for this session. Legacy app-server
     /// responses are converted to a profile at ingestion time using the
     /// response cwd so cached sessions do not reinterpret cwd-bound grants.
@@ -1420,7 +1417,6 @@ async fn thread_session_state_from_thread_response(
         service_tier,
         approval_policy,
         approvals_reviewer,
-        sandbox_policy,
         permission_profile,
         cwd,
         instruction_source_paths,