diff --git a/codex-rs/app-server-protocol/src/protocol/common.rs b/codex-rs/app-server-protocol/src/protocol/common.rs
index bd7fd8e28..83fa53b99 100644
--- a/codex-rs/app-server-protocol/src/protocol/common.rs
+++ b/codex-rs/app-server-protocol/src/protocol/common.rs
@@ -539,6 +539,7 @@ server_notification_definitions! {
     ReasoningSummaryPartAdded => "item/reasoning/summaryPartAdded" (v2::ReasoningSummaryPartAddedNotification),
     ReasoningTextDelta => "item/reasoning/textDelta" (v2::ReasoningTextDeltaNotification),
     ContextCompacted => "thread/compacted" (v2::ContextCompactedNotification),
+    DeprecationNotice => "deprecationNotice" (v2::DeprecationNoticeNotification),
 
     /// Notifies the user of world-writable directories on Windows, which cannot be protected by the sandbox.
     WindowsWorldWritableWarning => "windows/worldWritableWarning" (v2::WindowsWorldWritableWarningNotification),
diff --git a/codex-rs/app-server-protocol/src/protocol/v2.rs b/codex-rs/app-server-protocol/src/protocol/v2.rs
index 1d58cd1da..bd1ed62e7 100644
--- a/codex-rs/app-server-protocol/src/protocol/v2.rs
+++ b/codex-rs/app-server-protocol/src/protocol/v2.rs
@@ -1893,6 +1893,16 @@ pub struct AccountLoginCompletedNotification {
     pub error: Option<String>,
 }
 
+#[derive(Serialize, Deserialize, Debug, Clone, PartialEq, JsonSchema, TS)]
+#[serde(rename_all = "camelCase")]
+#[ts(export_to = "v2/")]
+pub struct DeprecationNoticeNotification {
+    /// Concise summary of what is deprecated.
+    pub summary: String,
+    /// Optional extra guidance, such as migration steps or rationale.
+    pub details: Option<String>,
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
diff --git a/codex-rs/app-server/src/bespoke_event_handling.rs b/codex-rs/app-server/src/bespoke_event_handling.rs
index dec9d8c08..f7e4f709e 100644
--- a/codex-rs/app-server/src/bespoke_event_handling.rs
+++ b/codex-rs/app-server/src/bespoke_event_handling.rs
@@ -15,6 +15,7 @@ use codex_app_server_protocol::CommandExecutionRequestApprovalParams;
 use codex_app_server_protocol::CommandExecutionRequestApprovalResponse;
 use codex_app_server_protocol::CommandExecutionStatus;
 use codex_app_server_protocol::ContextCompactedNotification;
+use codex_app_server_protocol::DeprecationNoticeNotification;
 use codex_app_server_protocol::ErrorNotification;
 use codex_app_server_protocol::ExecCommandApprovalParams;
 use codex_app_server_protocol::ExecCommandApprovalResponse;
@@ -283,6 +284,15 @@ pub(crate) async fn apply_bespoke_event_handling(
                 .send_server_notification(ServerNotification::ContextCompacted(notification))
                 .await;
         }
+        EventMsg::DeprecationNotice(event) => {
+            let notification = DeprecationNoticeNotification {
+                summary: event.summary,
+                details: event.details,
+            };
+            outgoing
+                .send_server_notification(ServerNotification::DeprecationNotice(notification))
+                .await;
+        }
         EventMsg::ReasoningContentDelta(event) => {
             let notification = ReasoningSummaryTextDeltaNotification {
                 thread_id: conversation_id.to_string(),