diff --git a/codex-rs/app-server/src/codex_message_processor.rs b/codex-rs/app-server/src/codex_message_processor.rs
index 6a1e6fbae801..6e81704752e1 100644
--- a/codex-rs/app-server/src/codex_message_processor.rs
+++ b/codex-rs/app-server/src/codex_message_processor.rs
@@ -4235,9 +4235,13 @@ impl CodexMessageProcessor {
                     thread_status,
                     /*has_live_in_progress_turn*/ false,
                 );
-                let permission_profile = thread_response_permission_profile(
-                    codex_thread.config_snapshot().await.permission_profile,
+                let config_snapshot = codex_thread.config_snapshot().await;
+                let sandbox = thread_response_sandbox_policy(
+                    &config_snapshot.permission_profile,
+                    config_snapshot.cwd.as_path(),
                 );
+                let permission_profile =
+                    thread_response_permission_profile(config_snapshot.permission_profile.clone());
 
                 let response = ThreadResumeResponse {
                     thread,
@@ -4248,7 +4252,7 @@ impl CodexMessageProcessor {
                     instruction_sources,
                     approval_policy: session_configured.approval_policy.into(),
                     approvals_reviewer: session_configured.approvals_reviewer.into(),
-                    sandbox: session_configured.sandbox_policy.into(),
+                    sandbox,
                     permission_profile,
                     reasoning_effort: session_configured.reasoning_effort,
                 };
@@ -4831,9 +4835,13 @@ impl CodexMessageProcessor {
                     .await,
                 /*has_in_progress_turn*/ false,
             );
-            let permission_profile = thread_response_permission_profile(
-                forked_thread.config_snapshot().await.permission_profile,
+            let config_snapshot = forked_thread.config_snapshot().await;
+            let sandbox = thread_response_sandbox_policy(
+                &config_snapshot.permission_profile,
+                config_snapshot.cwd.as_path(),
             );
+            let permission_profile =
+                thread_response_permission_profile(config_snapshot.permission_profile);
 
             let response = ThreadForkResponse {
                 thread: thread.clone(),
@@ -4844,7 +4852,7 @@ impl CodexMessageProcessor {
                 instruction_sources,
                 approval_policy: session_configured.approval_policy.into(),
                 approvals_reviewer: session_configured.approvals_reviewer.into(),
-                sandbox: session_configured.sandbox_policy.into(),
+                sandbox,
                 permission_profile,
                 reasoning_effort: session_configured.reasoning_effort,
             };
@@ -8091,13 +8099,14 @@ async fn handle_pending_thread_resume_request(
         service_tier,
         approval_policy,
         approvals_reviewer,
-        sandbox_policy,
+        sandbox_policy: _,
         permission_profile,
         cwd,
         reasoning_effort,
         ..
     } = pending.config_snapshot;
     let instruction_sources = pending.instruction_sources;
+    let sandbox = thread_response_sandbox_policy(&permission_profile, cwd.as_path());
     let permission_profile = thread_response_permission_profile(permission_profile);
 
     let response = ThreadResumeResponse {
@@ -8109,7 +8118,7 @@ async fn handle_pending_thread_resume_request(
         instruction_sources,
         approval_policy: approval_policy.into(),
         approvals_reviewer: approvals_reviewer.into(),
-        sandbox: sandbox_policy.into(),
+        sandbox,
         permission_profile,
         reasoning_effort,
     };
@@ -9240,6 +9249,20 @@ fn thread_response_permission_profile(
     Some(permission_profile.into())
 }
 
+fn thread_response_sandbox_policy(
+    permission_profile: &codex_protocol::models::PermissionProfile,
+    cwd: &Path,
+) -> codex_app_server_protocol::SandboxPolicy {
+    let file_system_policy = permission_profile.file_system_sandbox_policy();
+    let sandbox_policy = codex_sandboxing::compatibility_sandbox_policy_for_permission_profile(
+        permission_profile,
+        &file_system_policy,
+        permission_profile.network_sandbox_policy(),
+        cwd,
+    );
+    sandbox_policy.into()
+}
+
 fn requested_permissions_trust_project(overrides: &ConfigOverrides, cwd: &Path) -> bool {
     if matches!(
         overrides.sandbox_mode,
diff --git a/codex-rs/core/src/session/session.rs b/codex-rs/core/src/session/session.rs
index d4c0d337cf68..176865ee6cf1 100644
--- a/codex-rs/core/src/session/session.rs
+++ b/codex-rs/core/src/session/session.rs
@@ -867,7 +867,6 @@ impl Session {
             // Dispatch the SessionConfiguredEvent first and then report any errors.
             // If resuming, include converted initial messages in the payload so UIs can render them immediately.
             let initial_messages = initial_history.get_event_msgs();
-            let session_sandbox_policy = session_configuration.sandbox_policy();
             let events = std::iter::once(Event {
                 id: INITIAL_SUBMIT_ID.to_owned(),
                 msg: EventMsg::SessionConfigured(SessionConfiguredEvent {
@@ -879,8 +878,7 @@ impl Session {
                     service_tier: session_configuration.service_tier,
                     approval_policy: session_configuration.approval_policy.value(),
                     approvals_reviewer: session_configuration.approvals_reviewer,
-                    sandbox_policy: session_sandbox_policy.clone(),
-                    permission_profile: Some(session_configuration.permission_profile()),
+                    permission_profile: session_configuration.permission_profile(),
                     cwd: session_configuration.cwd.clone(),
                     reasoning_effort: session_configuration.collaboration_mode.reasoning_effort(),
                     history_log_id,
diff --git a/codex-rs/core/src/session/tests.rs b/codex-rs/core/src/session/tests.rs
index 283220e8fa2c..c9416ac2b46a 100644
--- a/codex-rs/core/src/session/tests.rs
+++ b/codex-rs/core/src/session/tests.rs
@@ -1527,17 +1527,12 @@ async fn session_configured_reports_permission_profile_for_external_sandbox() ->
 
     let test = builder.build(&server).await?;
 
-    assert_eq!(
-        test.session_configured.sandbox_policy,
-        expected_sandbox_policy
-    );
     let expected_permission_profile =
         codex_protocol::models::PermissionProfile::from_legacy_sandbox_policy(
             &expected_sandbox_policy,
         );
     assert_eq!(
-        test.session_configured.permission_profile,
-        Some(expected_permission_profile),
+        test.session_configured.permission_profile, expected_permission_profile,
         "ExternalSandbox is represented explicitly instead of as a lossy root-write profile"
     );
     Ok(())
diff --git a/codex-rs/exec/src/lib.rs b/codex-rs/exec/src/lib.rs
index 9e9d9bc148e1..fc3392db2fbf 100644
--- a/codex-rs/exec/src/lib.rs
+++ b/codex-rs/exec/src/lib.rs
@@ -1046,8 +1046,9 @@ fn session_configured_from_thread_response(
         service_tier,
         approval_policy,
         approvals_reviewer,
-        sandbox_policy,
-        permission_profile,
+        permission_profile: permission_profile.unwrap_or_else(|| {
+            PermissionProfile::from_legacy_sandbox_policy_for_cwd(&sandbox_policy, cwd.as_path())
+        }),
         cwd,
         reasoning_effort,
         history_log_id: 0,
diff --git a/codex-rs/exec/tests/event_processor_with_json_output.rs b/codex-rs/exec/tests/event_processor_with_json_output.rs
index 3a7b5d0fcc55..23dcd6733afa 100644
--- a/codex-rs/exec/tests/event_processor_with_json_output.rs
+++ b/codex-rs/exec/tests/event_processor_with_json_output.rs
@@ -28,9 +28,9 @@ use codex_app_server_protocol::TurnStartedNotification;
 use codex_app_server_protocol::TurnStatus;
 use codex_app_server_protocol::WebSearchAction as ApiWebSearchAction;
 use codex_protocol::ThreadId;
+use codex_protocol::models::PermissionProfile;
 use codex_protocol::models::WebSearchAction;
 use codex_protocol::protocol::AskForApproval;
-use codex_protocol::protocol::SandboxPolicy;
 use codex_protocol::protocol::SessionConfiguredEvent;
 use codex_utils_absolute_path::test_support::PathBufExt;
 use codex_utils_absolute_path::test_support::test_path_buf;
@@ -114,8 +114,7 @@ fn session_configured_produces_thread_started_event() {
         service_tier: None,
         approval_policy: AskForApproval::Never,
         approvals_reviewer: codex_protocol::config_types::ApprovalsReviewer::User,
-        sandbox_policy: SandboxPolicy::new_read_only_policy(),
-        permission_profile: None,
+        permission_profile: PermissionProfile::read_only(),
         cwd: test_path_buf("/tmp/project").abs(),
         reasoning_effort: None,
         history_log_id: 0,
diff --git a/codex-rs/mcp-server/src/outgoing_message.rs b/codex-rs/mcp-server/src/outgoing_message.rs
index 67ceb91dd819..78ef4cacffb8 100644
--- a/codex-rs/mcp-server/src/outgoing_message.rs
+++ b/codex-rs/mcp-server/src/outgoing_message.rs
@@ -231,10 +231,10 @@ mod tests {
 
     use anyhow::Result;
     use codex_protocol::ThreadId;
+    use codex_protocol::models::PermissionProfile;
     use codex_protocol::openai_models::ReasoningEffort;
     use codex_protocol::protocol::AskForApproval;
     use codex_protocol::protocol::EventMsg;
-    use codex_protocol::protocol::SandboxPolicy;
     use codex_protocol::protocol::SessionConfiguredEvent;
     use codex_utils_absolute_path::test_support::PathBufExt;
     use codex_utils_absolute_path::test_support::test_path_buf;
@@ -304,8 +304,7 @@ mod tests {
                 service_tier: None,
                 approval_policy: AskForApproval::Never,
                 approvals_reviewer: codex_protocol::config_types::ApprovalsReviewer::User,
-                sandbox_policy: SandboxPolicy::new_read_only_policy(),
-                permission_profile: None,
+                permission_profile: PermissionProfile::read_only(),
                 cwd: test_path_buf("/home/user/project").abs(),
                 reasoning_effort: Some(ReasoningEffort::default()),
                 history_log_id: 1,
@@ -349,8 +348,7 @@ mod tests {
             service_tier: None,
             approval_policy: AskForApproval::Never,
             approvals_reviewer: codex_protocol::config_types::ApprovalsReviewer::User,
-            sandbox_policy: SandboxPolicy::new_read_only_policy(),
-            permission_profile: None,
+            permission_profile: PermissionProfile::read_only(),
             cwd: test_path_buf("/home/user/project").abs(),
             reasoning_effort: Some(ReasoningEffort::default()),
             history_log_id: 1,
@@ -389,9 +387,7 @@ mod tests {
                 "model_provider_id": "test-provider",
                 "approval_policy": "never",
                 "approvals_reviewer": "user",
-                "sandbox_policy": {
-                    "type": "read-only"
-                },
+                "permission_profile": session_configured_event.permission_profile,
                 "cwd": test_path_buf("/home/user/project"),
                 "reasoning_effort": session_configured_event.reasoning_effort,
                 "history_log_id": session_configured_event.history_log_id,
@@ -419,8 +415,7 @@ mod tests {
             service_tier: None,
             approval_policy: AskForApproval::Never,
             approvals_reviewer: codex_protocol::config_types::ApprovalsReviewer::User,
-            sandbox_policy: SandboxPolicy::new_read_only_policy(),
-            permission_profile: None,
+            permission_profile: PermissionProfile::read_only(),
             cwd: test_path_buf("/home/user/project").abs(),
             reasoning_effort: Some(ReasoningEffort::default()),
             history_log_id: 1,
@@ -460,9 +455,7 @@ mod tests {
                 "model_provider_id": "test-provider",
                 "approval_policy": "never",
                 "approvals_reviewer": "user",
-                "sandbox_policy": {
-                    "type": "read-only"
-                },
+                "permission_profile": session_configured_event.permission_profile,
                 "cwd": test_path_buf("/home/user/project"),
                 "reasoning_effort": session_configured_event.reasoning_effort,
                 "history_log_id": session_configured_event.history_log_id,
diff --git a/codex-rs/protocol/src/protocol.rs b/codex-rs/protocol/src/protocol.rs
index 85ef863b81f0..c731dfae3a87 100644
--- a/codex-rs/protocol/src/protocol.rs
+++ b/codex-rs/protocol/src/protocol.rs
@@ -3541,7 +3541,7 @@ pub struct SessionNetworkProxyRuntime {
     pub socks_addr: String,
 }
 
-#[derive(Debug, Clone, Deserialize, Serialize, JsonSchema, TS)]
+#[derive(Debug, Clone, Serialize, JsonSchema, TS)]
 pub struct SessionConfiguredEvent {
     pub session_id: ThreadId,
     #[serde(skip_serializing_if = "Option::is_none")]
@@ -3569,16 +3569,8 @@ pub struct SessionConfiguredEvent {
     #[serde(default)]
     pub approvals_reviewer: ApprovalsReviewer,
 
-    /// Legacy sandbox projection for commands executed in the system.
-    ///
-    /// Consumers should prefer `permission_profile` when it is present. This
-    /// field remains available as a compatibility fallback for older emitters
-    /// and sessions that only expose legacy sandbox state.
-    pub sandbox_policy: SandboxPolicy,
-
     /// Canonical effective permissions for commands executed in the session.
-    #[serde(default, skip_serializing_if = "Option::is_none")]
-    pub permission_profile: Option<PermissionProfile>,
+    pub permission_profile: PermissionProfile,
 
     /// Working directory that should be treated as the *root* of the
     /// session.
@@ -3609,6 +3601,70 @@ pub struct SessionConfiguredEvent {
     pub rollout_path: Option<PathBuf>,
 }
 
+impl<'de> Deserialize<'de> for SessionConfiguredEvent {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: serde::Deserializer<'de>,
+    {
+        #[derive(Deserialize)]
+        struct Wire {
+            session_id: ThreadId,
+            forked_from_id: Option<ThreadId>,
+            #[serde(default)]
+            thread_name: Option<String>,
+            model: String,
+            model_provider_id: String,
+            service_tier: Option<ServiceTier>,
+            approval_policy: AskForApproval,
+            #[serde(default)]
+            approvals_reviewer: ApprovalsReviewer,
+            // `SessionConfiguredEvent` is persisted into rollout history. Older
+            // rollouts only have `sandbox_policy`, so accept it on deserialize
+            // and immediately project it into the canonical `permission_profile`.
+            sandbox_policy: Option<SandboxPolicy>,
+            permission_profile: Option<PermissionProfile>,
+            cwd: AbsolutePathBuf,
+            reasoning_effort: Option<ReasoningEffortConfig>,
+            history_log_id: u64,
+            history_entry_count: usize,
+            initial_messages: Option<Vec<EventMsg>>,
+            network_proxy: Option<SessionNetworkProxyRuntime>,
+            rollout_path: Option<PathBuf>,
+        }
+
+        let wire = Wire::deserialize(deserializer)?;
+        let permission_profile = match (wire.permission_profile, wire.sandbox_policy) {
+            (Some(permission_profile), _) => permission_profile,
+            (None, Some(sandbox_policy)) => PermissionProfile::from_legacy_sandbox_policy_for_cwd(
+                &sandbox_policy,
+                wire.cwd.as_path(),
+            ),
+            (None, None) => {
+                return Err(serde::de::Error::missing_field("permission_profile"));
+            }
+        };
+
+        Ok(Self {
+            session_id: wire.session_id,
+            forked_from_id: wire.forked_from_id,
+            thread_name: wire.thread_name,
+            model: wire.model,
+            model_provider_id: wire.model_provider_id,
+            service_tier: wire.service_tier,
+            approval_policy: wire.approval_policy,
+            approvals_reviewer: wire.approvals_reviewer,
+            permission_profile,
+            cwd: wire.cwd,
+            reasoning_effort: wire.reasoning_effort,
+            history_log_id: wire.history_log_id,
+            history_entry_count: wire.history_entry_count,
+            initial_messages: wire.initial_messages,
+            network_proxy: wire.network_proxy,
+            rollout_path: wire.rollout_path,
+        })
+    }
+}
+
 #[derive(Debug, Clone, Deserialize, Serialize, JsonSchema, TS)]
 pub struct ThreadNameUpdatedEvent {
     pub thread_id: ThreadId,
@@ -5088,6 +5144,7 @@ mod tests {
     fn serialize_event() -> Result<()> {
         let conversation_id = ThreadId::from_string("67e55044-10b1-426f-9247-bb680e5fe0c8")?;
         let rollout_file = NamedTempFile::new()?;
+        let permission_profile = PermissionProfile::read_only();
         let event = Event {
             id: "1234".to_string(),
             msg: EventMsg::SessionConfigured(SessionConfiguredEvent {
@@ -5099,8 +5156,7 @@ mod tests {
                 service_tier: None,
                 approval_policy: AskForApproval::Never,
                 approvals_reviewer: ApprovalsReviewer::User,
-                sandbox_policy: SandboxPolicy::new_read_only_policy(),
-                permission_profile: None,
+                permission_profile: permission_profile.clone(),
                 cwd: test_path_buf("/home/user/project").abs(),
                 reasoning_effort: Some(ReasoningEffortConfig::default()),
                 history_log_id: 0,
@@ -5120,9 +5176,7 @@ mod tests {
                 "model_provider_id": "openai",
                 "approval_policy": "never",
                 "approvals_reviewer": "user",
-                "sandbox_policy": {
-                    "type": "read-only"
-                },
+                "permission_profile": permission_profile,
                 "cwd": test_path_buf("/home/user/project"),
                 "reasoning_effort": "medium",
                 "history_log_id": 0,
@@ -5134,6 +5188,28 @@ mod tests {
         Ok(())
     }
 
+    #[test]
+    fn deserialize_legacy_session_configured_event_uses_sandbox_policy() -> Result<()> {
+        let cwd = test_path_buf("/home/user/project");
+        let value = json!({
+            "session_id": "67e55044-10b1-426f-9247-bb680e5fe0c8",
+            "model": "codex-mini-latest",
+            "model_provider_id": "openai",
+            "approval_policy": "never",
+            "approvals_reviewer": "user",
+            "sandbox_policy": {
+                "type": "read-only"
+            },
+            "cwd": cwd,
+            "history_log_id": 0,
+            "history_entry_count": 0,
+        });
+
+        let event: SessionConfiguredEvent = serde_json::from_value(value)?;
+        assert_eq!(event.permission_profile, PermissionProfile::read_only());
+        Ok(())
+    }
+
     #[test]
     fn vec_u8_as_base64_serialization_and_deserialization() -> Result<()> {
         let event = ExecCommandOutputDeltaEvent {
diff --git a/codex-rs/tui/src/app/config_persistence.rs b/codex-rs/tui/src/app/config_persistence.rs
index 9f6b63122636..316465537488 100644
--- a/codex-rs/tui/src/app/config_persistence.rs
+++ b/codex-rs/tui/src/app/config_persistence.rs
@@ -556,6 +556,7 @@ mod tests {
     use crate::app::test_support::app_enabled_in_effective_config;
     use crate::app::test_support::make_test_app;
     use crate::test_support::PathBufExt;
+    use codex_protocol::models::PermissionProfile;
     use codex_protocol::protocol::Event;
     use codex_protocol::protocol::EventMsg;
     use codex_protocol::protocol::SessionConfiguredEvent;
@@ -653,8 +654,7 @@ mod tests {
                 service_tier: None,
                 approval_policy: AskForApproval::Never,
                 approvals_reviewer: ApprovalsReviewer::User,
-                sandbox_policy: SandboxPolicy::new_read_only_policy(),
-                permission_profile: None,
+                permission_profile: PermissionProfile::read_only(),
                 cwd: next_cwd.clone().abs(),
                 reasoning_effort: None,
                 history_log_id: 0,
diff --git a/codex-rs/tui/src/app/tests.rs b/codex-rs/tui/src/app/tests.rs
index 8a08f8bf165d..6c82dac63853 100644
--- a/codex-rs/tui/src/app/tests.rs
+++ b/codex-rs/tui/src/app/tests.rs
@@ -3566,8 +3566,7 @@ async fn render_clear_ui_header_after_long_transcript_for_snapshot() -> String {
             service_tier: None,
             approval_policy: AskForApproval::Never,
             approvals_reviewer: ApprovalsReviewer::User,
-            sandbox_policy: SandboxPolicy::new_read_only_policy(),
-            permission_profile: None,
+            permission_profile: PermissionProfile::read_only(),
             cwd: test_path_buf("/tmp/project").abs(),
             reasoning_effort: Some(ReasoningEffortConfig::High),
             history_log_id: 0,
@@ -4317,8 +4316,7 @@ async fn backtrack_selection_with_duplicate_history_targets_unique_turn() {
             service_tier: None,
             approval_policy: AskForApproval::Never,
             approvals_reviewer: ApprovalsReviewer::User,
-            sandbox_policy: SandboxPolicy::new_read_only_policy(),
-            permission_profile: None,
+            permission_profile: PermissionProfile::read_only(),
             cwd: test_path_buf("/home/user/project").abs(),
             reasoning_effort: None,
             history_log_id: 0,
@@ -4381,8 +4379,7 @@ async fn backtrack_selection_with_duplicate_history_targets_unique_turn() {
             service_tier: None,
             approval_policy: AskForApproval::Never,
             approvals_reviewer: ApprovalsReviewer::User,
-            sandbox_policy: SandboxPolicy::new_read_only_policy(),
-            permission_profile: None,
+            permission_profile: PermissionProfile::read_only(),
             cwd: test_path_buf("/home/user/project").abs(),
             reasoning_effort: None,
             history_log_id: 0,
@@ -4475,8 +4472,7 @@ async fn backtrack_resubmit_preserves_data_image_urls_in_user_turn() {
             service_tier: None,
             approval_policy: AskForApproval::Never,
             approvals_reviewer: ApprovalsReviewer::User,
-            sandbox_policy: SandboxPolicy::new_read_only_policy(),
-            permission_profile: None,
+            permission_profile: PermissionProfile::read_only(),
             cwd: test_path_buf("/home/user/project").abs(),
             reasoning_effort: None,
             history_log_id: 0,
@@ -4859,8 +4855,7 @@ async fn new_session_requests_shutdown_for_previous_conversation() {
         service_tier: None,
         approval_policy: AskForApproval::Never,
         approvals_reviewer: ApprovalsReviewer::User,
-        sandbox_policy: SandboxPolicy::new_read_only_policy(),
-        permission_profile: None,
+        permission_profile: PermissionProfile::read_only(),
         cwd: test_path_buf("/home/user/project").abs(),
         reasoning_effort: None,
         history_log_id: 0,
@@ -4972,8 +4967,7 @@ async fn clear_only_ui_reset_preserves_chat_session_state() {
             service_tier: None,
             approval_policy: AskForApproval::Never,
             approvals_reviewer: ApprovalsReviewer::User,
-            sandbox_policy: SandboxPolicy::new_read_only_policy(),
-            permission_profile: None,
+            permission_profile: PermissionProfile::read_only(),
             cwd: test_path_buf("/tmp/project").abs(),
             reasoning_effort: None,
             history_log_id: 0,
diff --git a/codex-rs/tui/src/chatwidget.rs b/codex-rs/tui/src/chatwidget.rs
index f69eea4afce8..2b1871886038 100644
--- a/codex-rs/tui/src/chatwidget.rs
+++ b/codex-rs/tui/src/chatwidget.rs
@@ -142,12 +142,8 @@ use codex_protocol::items::AgentMessageContent;
 use codex_protocol::items::AgentMessageItem;
 use codex_protocol::items::UserMessageItem;
 use codex_protocol::models::MessagePhase;
-use codex_protocol::models::PermissionProfile;
-use codex_protocol::models::SandboxEnforcement;
 use codex_protocol::models::local_image_label_text;
 use codex_protocol::parse_command::ParsedCommand;
-use codex_protocol::permissions::FileSystemSandboxPolicy;
-use codex_protocol::permissions::NetworkSandboxPolicy;
 use codex_protocol::plan_tool::PlanItemArg as UpdatePlanItemArg;
 use codex_protocol::plan_tool::StepStatus as UpdatePlanItemStatus;
 #[cfg(test)]
@@ -1620,8 +1616,7 @@ fn thread_session_state_to_legacy_event(
         service_tier: session.service_tier,
         approval_policy: session.approval_policy,
         approvals_reviewer: session.approvals_reviewer,
-        sandbox_policy: session.sandbox_policy,
-        permission_profile: Some(session.permission_profile),
+        permission_profile: session.permission_profile,
         cwd: session.cwd,
         reasoning_effort: session.reasoning_effort,
         history_log_id: session.history_log_id,
@@ -2349,32 +2344,14 @@ impl ChatWidget {
             self.config.permissions.approval_policy =
                 Constrained::allow_only(event.approval_policy);
         }
-        let permission_sync = match event.permission_profile.clone() {
-            Some(permission_profile) => self
-                .config
-                .permissions
-                .set_permission_profile(permission_profile),
-            None => self
-                .config
-                .permissions
-                .set_legacy_sandbox_policy(event.sandbox_policy.clone(), event.cwd.as_path()),
-        };
+        let permission_sync = self
+            .config
+            .permissions
+            .set_permission_profile(event.permission_profile.clone());
         if let Err(err) = permission_sync {
             tracing::warn!(%err, "failed to sync permissions from SessionConfigured");
-            let permission_profile = event.permission_profile.clone().unwrap_or_else(|| {
-                let file_system_sandbox_policy =
-                    FileSystemSandboxPolicy::from_legacy_sandbox_policy_for_cwd(
-                        &event.sandbox_policy,
-                        event.cwd.as_path(),
-                    );
-                PermissionProfile::from_runtime_permissions_with_enforcement(
-                    SandboxEnforcement::from_legacy_sandbox_policy(&event.sandbox_policy),
-                    &file_system_sandbox_policy,
-                    NetworkSandboxPolicy::from(&event.sandbox_policy),
-                )
-            });
             self.config.permissions.permission_profile =
-                Constrained::allow_only(permission_profile);
+                Constrained::allow_only(event.permission_profile.clone());
         }
         self.config.approvals_reviewer = event.approvals_reviewer;
         self.status_line_project_root_name_cache = None;
diff --git a/codex-rs/tui/src/chatwidget/tests/composer_submission.rs b/codex-rs/tui/src/chatwidget/tests/composer_submission.rs
index 302c4ea38c1c..d21febaa8128 100644
--- a/codex-rs/tui/src/chatwidget/tests/composer_submission.rs
+++ b/codex-rs/tui/src/chatwidget/tests/composer_submission.rs
@@ -16,8 +16,7 @@ async fn submission_preserves_text_elements_and_local_images() {
         service_tier: None,
         approval_policy: AskForApproval::Never,
         approvals_reviewer: ApprovalsReviewer::User,
-        sandbox_policy: SandboxPolicy::new_read_only_policy(),
-        permission_profile: None,
+        permission_profile: PermissionProfile::read_only(),
         cwd: test_path_buf("/home/user/project").abs(),
         reasoning_effort: Some(ReasoningEffortConfig::default()),
         history_log_id: 0,
@@ -121,8 +120,7 @@ async fn submission_includes_configured_permission_profile() {
         service_tier: None,
         approval_policy: AskForApproval::Never,
         approvals_reviewer: ApprovalsReviewer::User,
-        sandbox_policy: SandboxPolicy::new_read_only_policy(),
-        permission_profile: Some(expected_permission_profile.clone()),
+        permission_profile: expected_permission_profile.clone(),
         cwd: test_path_buf("/home/user/project").abs(),
         reasoning_effort: Some(ReasoningEffortConfig::default()),
         history_log_id: 0,
@@ -172,10 +170,7 @@ async fn submission_keeps_profile_when_legacy_projection_is_external() {
         service_tier: None,
         approval_policy: AskForApproval::Never,
         approvals_reviewer: ApprovalsReviewer::User,
-        sandbox_policy: SandboxPolicy::ExternalSandbox {
-            network_access: codex_protocol::protocol::NetworkAccess::Restricted,
-        },
-        permission_profile: Some(expected_permission_profile.clone()),
+        permission_profile: expected_permission_profile.clone(),
         cwd: test_path_buf("/home/user/project").abs(),
         reasoning_effort: Some(ReasoningEffortConfig::default()),
         history_log_id: 0,
@@ -218,8 +213,7 @@ async fn submission_with_remote_and_local_images_keeps_local_placeholder_numberi
         service_tier: None,
         approval_policy: AskForApproval::Never,
         approvals_reviewer: ApprovalsReviewer::User,
-        sandbox_policy: SandboxPolicy::new_read_only_policy(),
-        permission_profile: None,
+        permission_profile: PermissionProfile::read_only(),
         cwd: test_path_buf("/home/user/project").abs(),
         reasoning_effort: Some(ReasoningEffortConfig::default()),
         history_log_id: 0,
@@ -314,8 +308,7 @@ async fn enter_with_only_remote_images_submits_user_turn() {
         service_tier: None,
         approval_policy: AskForApproval::Never,
         approvals_reviewer: ApprovalsReviewer::User,
-        sandbox_policy: SandboxPolicy::new_read_only_policy(),
-        permission_profile: None,
+        permission_profile: PermissionProfile::read_only(),
         cwd: test_path_buf("/home/user/project").abs(),
         reasoning_effort: Some(ReasoningEffortConfig::default()),
         history_log_id: 0,
@@ -380,8 +373,7 @@ async fn shift_enter_with_only_remote_images_does_not_submit_user_turn() {
         service_tier: None,
         approval_policy: AskForApproval::Never,
         approvals_reviewer: ApprovalsReviewer::User,
-        sandbox_policy: SandboxPolicy::new_read_only_policy(),
-        permission_profile: None,
+        permission_profile: PermissionProfile::read_only(),
         cwd: test_path_buf("/home/user/project").abs(),
         reasoning_effort: Some(ReasoningEffortConfig::default()),
         history_log_id: 0,
@@ -421,8 +413,7 @@ async fn enter_with_only_remote_images_does_not_submit_when_modal_is_active() {
         service_tier: None,
         approval_policy: AskForApproval::Never,
         approvals_reviewer: ApprovalsReviewer::User,
-        sandbox_policy: SandboxPolicy::new_read_only_policy(),
-        permission_profile: None,
+        permission_profile: PermissionProfile::read_only(),
         cwd: test_path_buf("/home/user/project").abs(),
         reasoning_effort: Some(ReasoningEffortConfig::default()),
         history_log_id: 0,
@@ -462,8 +453,7 @@ async fn enter_with_only_remote_images_does_not_submit_when_input_disabled() {
         service_tier: None,
         approval_policy: AskForApproval::Never,
         approvals_reviewer: ApprovalsReviewer::User,
-        sandbox_policy: SandboxPolicy::new_read_only_policy(),
-        permission_profile: None,
+        permission_profile: PermissionProfile::read_only(),
         cwd: test_path_buf("/home/user/project").abs(),
         reasoning_effort: Some(ReasoningEffortConfig::default()),
         history_log_id: 0,
@@ -506,8 +496,7 @@ async fn submission_prefers_selected_duplicate_skill_path() {
         service_tier: None,
         approval_policy: AskForApproval::Never,
         approvals_reviewer: ApprovalsReviewer::User,
-        sandbox_policy: SandboxPolicy::new_read_only_policy(),
-        permission_profile: None,
+        permission_profile: PermissionProfile::read_only(),
         cwd: test_path_buf("/home/user/project").abs(),
         reasoning_effort: Some(ReasoningEffortConfig::default()),
         history_log_id: 0,
diff --git a/codex-rs/tui/src/chatwidget/tests/exec_flow.rs b/codex-rs/tui/src/chatwidget/tests/exec_flow.rs
index 4d87914aa40a..ec1d03f9fc50 100644
--- a/codex-rs/tui/src/chatwidget/tests/exec_flow.rs
+++ b/codex-rs/tui/src/chatwidget/tests/exec_flow.rs
@@ -1004,8 +1004,7 @@ async fn bang_shell_enter_while_task_running_submits_run_user_shell_command() {
         service_tier: None,
         approval_policy: AskForApproval::Never,
         approvals_reviewer: ApprovalsReviewer::User,
-        sandbox_policy: SandboxPolicy::new_read_only_policy(),
-        permission_profile: None,
+        permission_profile: PermissionProfile::read_only(),
         cwd: test_path_buf("/home/user/project").abs(),
         reasoning_effort: Some(ReasoningEffortConfig::default()),
         history_log_id: 0,
diff --git a/codex-rs/tui/src/chatwidget/tests/history_replay.rs b/codex-rs/tui/src/chatwidget/tests/history_replay.rs
index 77f52524f47e..443cac0532d2 100644
--- a/codex-rs/tui/src/chatwidget/tests/history_replay.rs
+++ b/codex-rs/tui/src/chatwidget/tests/history_replay.rs
@@ -24,8 +24,7 @@ async fn resumed_initial_messages_render_history() {
         service_tier: None,
         approval_policy: AskForApproval::Never,
         approvals_reviewer: ApprovalsReviewer::User,
-        sandbox_policy: SandboxPolicy::new_read_only_policy(),
-        permission_profile: None,
+        permission_profile: codex_protocol::models::PermissionProfile::read_only(),
         cwd: test_path_buf("/home/user/project").abs(),
         reasoning_effort: Some(ReasoningEffortConfig::default()),
         history_log_id: 0,
@@ -138,8 +137,7 @@ async fn replayed_user_message_preserves_text_elements_and_local_images() {
         service_tier: None,
         approval_policy: AskForApproval::Never,
         approvals_reviewer: ApprovalsReviewer::User,
-        sandbox_policy: SandboxPolicy::new_read_only_policy(),
-        permission_profile: None,
+        permission_profile: codex_protocol::models::PermissionProfile::read_only(),
         cwd: test_path_buf("/home/user/project").abs(),
         reasoning_effort: Some(ReasoningEffortConfig::default()),
         history_log_id: 0,
@@ -200,8 +198,7 @@ async fn replayed_user_message_preserves_remote_image_urls() {
         service_tier: None,
         approval_policy: AskForApproval::Never,
         approvals_reviewer: ApprovalsReviewer::User,
-        sandbox_policy: SandboxPolicy::new_read_only_policy(),
-        permission_profile: None,
+        permission_profile: codex_protocol::models::PermissionProfile::read_only(),
         cwd: test_path_buf("/home/user/project").abs(),
         reasoning_effort: Some(ReasoningEffortConfig::default()),
         history_log_id: 0,
@@ -256,7 +253,6 @@ async fn session_configured_syncs_widget_config_permissions_and_cwd() {
         .expect("set sandbox policy");
     chat.config.cwd = test_path_buf("/home/user/main").abs();
 
-    let legacy_fallback_sandbox = SandboxPolicy::new_read_only_policy();
     let expected_cwd = test_path_buf("/home/user/sub-agent").abs();
     let expected_file_system_policy = FileSystemSandboxPolicy::restricted(vec![
         FileSystemSandboxEntry {
@@ -289,8 +285,7 @@ async fn session_configured_syncs_widget_config_permissions_and_cwd() {
         service_tier: None,
         approval_policy: AskForApproval::Never,
         approvals_reviewer: ApprovalsReviewer::User,
-        sandbox_policy: legacy_fallback_sandbox,
-        permission_profile: Some(expected_permission_profile.clone()),
+        permission_profile: expected_permission_profile.clone(),
         cwd: expected_cwd.clone(),
         reasoning_effort: Some(ReasoningEffortConfig::default()),
         history_log_id: 0,
@@ -355,8 +350,9 @@ async fn session_configured_external_sandbox_keeps_external_runtime_policy() {
         service_tier: None,
         approval_policy: AskForApproval::Never,
         approvals_reviewer: ApprovalsReviewer::User,
-        sandbox_policy: expected_sandbox.clone(),
-        permission_profile: None,
+        permission_profile: codex_protocol::models::PermissionProfile::External {
+            network: NetworkSandboxPolicy::Restricted,
+        },
         cwd: test_path_buf("/home/user/external").abs(),
         reasoning_effort: Some(ReasoningEffortConfig::default()),
         history_log_id: 0,
@@ -405,8 +401,7 @@ async fn replayed_user_message_with_only_remote_images_renders_history_cell() {
         service_tier: None,
         approval_policy: AskForApproval::Never,
         approvals_reviewer: ApprovalsReviewer::User,
-        sandbox_policy: SandboxPolicy::new_read_only_policy(),
-        permission_profile: None,
+        permission_profile: codex_protocol::models::PermissionProfile::read_only(),
         cwd: test_path_buf("/home/user/project").abs(),
         reasoning_effort: Some(ReasoningEffortConfig::default()),
         history_log_id: 0,
@@ -459,8 +454,7 @@ async fn replayed_user_message_with_only_local_images_does_not_render_history_ce
         service_tier: None,
         approval_policy: AskForApproval::Never,
         approvals_reviewer: ApprovalsReviewer::User,
-        sandbox_policy: SandboxPolicy::new_read_only_policy(),
-        permission_profile: None,
+        permission_profile: codex_protocol::models::PermissionProfile::read_only(),
         cwd: test_path_buf("/home/user/project").abs(),
         reasoning_effort: Some(ReasoningEffortConfig::default()),
         history_log_id: 0,
@@ -781,8 +775,7 @@ async fn replayed_reasoning_item_hides_raw_reasoning_when_disabled() {
             service_tier: None,
             approval_policy: AskForApproval::Never,
             approvals_reviewer: ApprovalsReviewer::User,
-            sandbox_policy: SandboxPolicy::new_read_only_policy(),
-            permission_profile: None,
+            permission_profile: codex_protocol::models::PermissionProfile::read_only(),
             cwd: test_project_path().abs(),
             reasoning_effort: None,
             history_log_id: 0,
@@ -829,8 +822,7 @@ async fn replayed_reasoning_item_shows_raw_reasoning_when_enabled() {
             service_tier: None,
             approval_policy: AskForApproval::Never,
             approvals_reviewer: ApprovalsReviewer::User,
-            sandbox_policy: SandboxPolicy::new_read_only_policy(),
-            permission_profile: None,
+            permission_profile: codex_protocol::models::PermissionProfile::read_only(),
             cwd: test_project_path().abs(),
             reasoning_effort: None,
             history_log_id: 0,
diff --git a/codex-rs/tui/src/chatwidget/tests/permissions.rs b/codex-rs/tui/src/chatwidget/tests/permissions.rs
index 388bc67f81c3..4666e680490b 100644
--- a/codex-rs/tui/src/chatwidget/tests/permissions.rs
+++ b/codex-rs/tui/src/chatwidget/tests/permissions.rs
@@ -483,8 +483,7 @@ async fn permissions_selection_marks_auto_review_current_after_session_configure
             service_tier: None,
             approval_policy: AskForApproval::OnRequest,
             approvals_reviewer: ApprovalsReviewer::AutoReview,
-            sandbox_policy: SandboxPolicy::new_workspace_write_policy(),
-            permission_profile: None,
+            permission_profile: PermissionProfile::workspace_write(),
             cwd: test_project_path().abs(),
             reasoning_effort: None,
             history_log_id: 0,
@@ -519,6 +518,13 @@ async fn permissions_selection_marks_auto_review_current_with_custom_workspace_w
         .set_enabled(Feature::GuardianApproval, /*enabled*/ true);
 
     let extra_root = test_path_buf("/tmp/guardian-approvals-extra").abs();
+    let cwd = test_project_path().abs();
+    let permission_profile = PermissionProfile::workspace_write_with(
+        &[extra_root],
+        codex_protocol::protocol::NetworkSandboxPolicy::Restricted,
+        /*exclude_tmpdir_env_var*/ false,
+        /*exclude_slash_tmp*/ false,
+    );
 
     chat.handle_codex_event(Event {
         id: "session-configured-custom-workspace".to_string(),
@@ -531,14 +537,8 @@ async fn permissions_selection_marks_auto_review_current_with_custom_workspace_w
             service_tier: None,
             approval_policy: AskForApproval::OnRequest,
             approvals_reviewer: ApprovalsReviewer::AutoReview,
-            sandbox_policy: SandboxPolicy::WorkspaceWrite {
-                writable_roots: vec![extra_root],
-                network_access: false,
-                exclude_tmpdir_env_var: false,
-                exclude_slash_tmp: false,
-            },
-            permission_profile: None,
-            cwd: test_project_path().abs(),
+            permission_profile,
+            cwd,
             reasoning_effort: None,
             history_log_id: 0,
             history_entry_count: 0,
diff --git a/codex-rs/tui/src/chatwidget/tests/plan_mode.rs b/codex-rs/tui/src/chatwidget/tests/plan_mode.rs
index 65f6ae0c310d..c6e1f73763a7 100644
--- a/codex-rs/tui/src/chatwidget/tests/plan_mode.rs
+++ b/codex-rs/tui/src/chatwidget/tests/plan_mode.rs
@@ -1059,8 +1059,7 @@ async fn submit_user_message_emits_structured_plugin_mentions_from_bindings() {
         service_tier: None,
         approval_policy: AskForApproval::Never,
         approvals_reviewer: ApprovalsReviewer::User,
-        sandbox_policy: SandboxPolicy::new_read_only_policy(),
-        permission_profile: None,
+        permission_profile: PermissionProfile::read_only(),
         cwd: test_path_buf("/home/user/project").abs(),
         reasoning_effort: Some(ReasoningEffortConfig::default()),
         history_log_id: 0,
@@ -1305,8 +1304,7 @@ async fn plan_slash_command_with_args_submits_prompt_in_plan_mode() {
         service_tier: None,
         approval_policy: AskForApproval::Never,
         approvals_reviewer: ApprovalsReviewer::User,
-        sandbox_policy: SandboxPolicy::new_read_only_policy(),
-        permission_profile: None,
+        permission_profile: PermissionProfile::read_only(),
         cwd: test_path_buf("/home/user/project").abs(),
         reasoning_effort: Some(ReasoningEffortConfig::default()),
         history_log_id: 0,
diff --git a/codex-rs/tui/src/chatwidget/tests/status_and_layout.rs b/codex-rs/tui/src/chatwidget/tests/status_and_layout.rs
index d7aefbe4b4fa..19890a5d3c44 100644
--- a/codex-rs/tui/src/chatwidget/tests/status_and_layout.rs
+++ b/codex-rs/tui/src/chatwidget/tests/status_and_layout.rs
@@ -1741,8 +1741,7 @@ async fn session_configured_clears_goal_status_footer() {
             service_tier: None,
             approval_policy: AskForApproval::Never,
             approvals_reviewer: ApprovalsReviewer::User,
-            sandbox_policy: SandboxPolicy::new_read_only_policy(),
-            permission_profile: None,
+            permission_profile: PermissionProfile::read_only(),
             cwd: test_path_buf("/home/user/project").abs(),
             reasoning_effort: Some(ReasoningEffortConfig::default()),
             history_log_id: 0,
diff --git a/codex-rs/tui/src/history_cell.rs b/codex-rs/tui/src/history_cell.rs
index 33e2f25c637f..af77b6ecb853 100644
--- a/codex-rs/tui/src/history_cell.rs
+++ b/codex-rs/tui/src/history_cell.rs
@@ -54,6 +54,8 @@ use codex_protocol::account::PlanType;
 use codex_protocol::mcp::Resource;
 #[cfg(test)]
 use codex_protocol::mcp::ResourceTemplate;
+use codex_protocol::models::ManagedFileSystemPermissions;
+use codex_protocol::models::PermissionProfile;
 use codex_protocol::models::WebSearchAction;
 use codex_protocol::models::local_image_label_text;
 use codex_protocol::openai_models::ReasoningEffort as ReasoningEffortConfig;
@@ -64,7 +66,6 @@ use codex_protocol::protocol::AskForApproval;
 use codex_protocol::protocol::FileChange;
 use codex_protocol::protocol::McpAuthStatus;
 use codex_protocol::protocol::McpInvocation;
-use codex_protocol::protocol::SandboxPolicy;
 use codex_protocol::protocol::SessionConfiguredEvent;
 use codex_protocol::request_user_input::RequestUserInputAnswer;
 use codex_protocol::request_user_input::RequestUserInputQuestion;
@@ -1240,7 +1241,7 @@ pub(crate) fn new_session_info(
         model,
         reasoning_effort,
         approval_policy,
-        sandbox_policy,
+        permission_profile,
         ..
     } = event;
     // Header box rendered as history (so it appears at the very top)
@@ -1251,7 +1252,7 @@ pub(crate) fn new_session_info(
         config.cwd.to_path_buf(),
         CODEX_CLI_VERSION,
     )
-    .with_yolo_mode(has_yolo_permissions(approval_policy, &sandbox_policy));
+    .with_yolo_mode(has_yolo_permissions(approval_policy, &permission_profile));
     let mut parts: Vec<Box<dyn HistoryCell>> = vec![Box::new(header)];
 
     if is_first_event {
@@ -1313,14 +1314,23 @@ pub(crate) fn new_session_info(
 pub(crate) fn is_yolo_mode(config: &Config) -> bool {
     has_yolo_permissions(
         config.permissions.approval_policy.value(),
-        &config
-            .permissions
-            .legacy_sandbox_policy(config.cwd.as_path()),
+        &config.permissions.permission_profile(),
     )
 }
 
-fn has_yolo_permissions(approval_policy: AskForApproval, sandbox_policy: &SandboxPolicy) -> bool {
-    approval_policy == AskForApproval::Never && *sandbox_policy == SandboxPolicy::DangerFullAccess
+fn has_yolo_permissions(
+    approval_policy: AskForApproval,
+    permission_profile: &PermissionProfile,
+) -> bool {
+    approval_policy == AskForApproval::Never
+        && matches!(
+            permission_profile,
+            PermissionProfile::Disabled
+                | PermissionProfile::Managed {
+                    file_system: ManagedFileSystemPermissions::Unrestricted,
+                    network: codex_protocol::protocol::NetworkSandboxPolicy::Enabled,
+                }
+        )
 }
 
 pub(crate) fn new_user_prompt(
@@ -2993,7 +3003,6 @@ mod tests {
     use codex_protocol::parse_command::ParsedCommand;
     use codex_protocol::protocol::AskForApproval;
     use codex_protocol::protocol::McpAuthStatus;
-    use codex_protocol::protocol::SandboxPolicy;
     use codex_protocol::protocol::SessionConfiguredEvent;
     use dirs::home_dir;
     use pretty_assertions::assert_eq;
@@ -3184,8 +3193,7 @@ mod tests {
             service_tier: None,
             approval_policy: AskForApproval::Never,
             approvals_reviewer: codex_protocol::config_types::ApprovalsReviewer::User,
-            sandbox_policy: SandboxPolicy::new_read_only_policy(),
-            permission_profile: None,
+            permission_profile: PermissionProfile::read_only(),
             cwd: test_path_buf("/tmp/project").abs(),
             reasoning_effort: None,
             history_log_id: 0,
@@ -4205,6 +4213,31 @@ mod tests {
         insta::assert_snapshot!(rendered);
     }
 
+    #[test]
+    fn yolo_mode_includes_managed_full_access_profiles() {
+        let permission_profile = PermissionProfile::Managed {
+            file_system: ManagedFileSystemPermissions::Unrestricted,
+            network: codex_protocol::protocol::NetworkSandboxPolicy::Enabled,
+        };
+
+        assert!(has_yolo_permissions(
+            AskForApproval::Never,
+            &permission_profile
+        ));
+    }
+
+    #[test]
+    fn yolo_mode_excludes_external_sandbox_profiles() {
+        let permission_profile = PermissionProfile::External {
+            network: codex_protocol::protocol::NetworkSandboxPolicy::Enabled,
+        };
+
+        assert!(!has_yolo_permissions(
+            AskForApproval::Never,
+            &permission_profile
+        ));
+    }
+
     #[test]
     fn session_header_directory_center_truncates() {
         let mut dir = home_dir().expect("home directory");