diff --git a/codex-rs/Cargo.lock b/codex-rs/Cargo.lock
index 6b5b5afdf..5a32a8e18 100644
--- a/codex-rs/Cargo.lock
+++ b/codex-rs/Cargo.lock
@@ -3776,7 +3776,6 @@ dependencies = [
  "chrono",
  "codex-file-search",
  "codex-git-utils",
- "codex-login",
  "codex-otel",
  "codex-protocol",
  "codex-state",
diff --git a/codex-rs/analytics/src/analytics_client_tests.rs b/codex-rs/analytics/src/analytics_client_tests.rs
index 38d953961..9f8df04b4 100644
--- a/codex-rs/analytics/src/analytics_client_tests.rs
+++ b/codex-rs/analytics/src/analytics_client_tests.rs
@@ -168,6 +168,17 @@ use std::sync::Arc;
 use std::sync::Mutex;
 use tokio::sync::mpsc;
 
+const TEST_PRODUCT_CLIENT_ID: &str = "codex_work_desktop";
+
+fn test_tracking_context(thread_id: &str, turn_id: &str) -> TrackEventsContext {
+    TrackEventsContext {
+        model_slug: "gpt-5".to_string(),
+        thread_id: thread_id.to_string(),
+        turn_id: turn_id.to_string(),
+        product_client_id: TEST_PRODUCT_CLIENT_ID.to_string(),
+    }
+}
+
 fn sample_thread_with_metadata(
     thread_id: &str,
     ephemeral: bool,
@@ -1024,11 +1035,7 @@ fn normalize_path_for_skill_id_repo_root_not_in_skill_path_uses_absolute_path()
 
 #[test]
 fn app_mentioned_event_serializes_expected_shape() {
-    let tracking = TrackEventsContext {
-        model_slug: "gpt-5".to_string(),
-        thread_id: "thread-1".to_string(),
-        turn_id: "turn-1".to_string(),
-    };
+    let tracking = test_tracking_context("thread-1", "turn-1");
     let event = TrackEventRequest::AppMentioned(CodexAppMentionedEventRequest {
         event_type: "codex_app_mentioned",
         event_params: codex_app_metadata(
@@ -1052,7 +1059,7 @@ fn app_mentioned_event_serializes_expected_shape() {
                 "thread_id": "thread-1",
                 "turn_id": "turn-1",
                 "app_name": "Calendar",
-                "product_client_id": originator().value,
+                "product_client_id": TEST_PRODUCT_CLIENT_ID,
                 "invoke_type": "explicit",
                 "model_slug": "gpt-5"
             }
@@ -1062,11 +1069,7 @@ fn app_mentioned_event_serializes_expected_shape() {
 
 #[test]
 fn app_used_event_serializes_expected_shape() {
-    let tracking = TrackEventsContext {
-        model_slug: "gpt-5".to_string(),
-        thread_id: "thread-2".to_string(),
-        turn_id: "turn-2".to_string(),
-    };
+    let tracking = test_tracking_context("thread-2", "turn-2");
     let event = TrackEventRequest::AppUsed(CodexAppUsedEventRequest {
         event_type: "codex_app_used",
         event_params: codex_app_metadata(
@@ -1090,7 +1093,7 @@ fn app_used_event_serializes_expected_shape() {
                 "thread_id": "thread-2",
                 "turn_id": "turn-2",
                 "app_name": "Google Drive",
-                "product_client_id": originator().value,
+                "product_client_id": TEST_PRODUCT_CLIENT_ID,
                 "invoke_type": "implicit",
                 "model_slug": "gpt-5"
             }
@@ -1381,16 +1384,8 @@ fn app_used_dedupe_is_keyed_by_turn_and_connector() {
         invocation_type: Some(InvocationType::Implicit),
     };
 
-    let turn_1 = TrackEventsContext {
-        model_slug: "gpt-5".to_string(),
-        thread_id: "thread-1".to_string(),
-        turn_id: "turn-1".to_string(),
-    };
-    let turn_2 = TrackEventsContext {
-        model_slug: "gpt-5".to_string(),
-        thread_id: "thread-1".to_string(),
-        turn_id: "turn-2".to_string(),
-    };
+    let turn_1 = test_tracking_context("thread-1", "turn-1");
+    let turn_2 = test_tracking_context("thread-1", "turn-2");
 
     assert_eq!(queue.should_enqueue_app_used(&turn_1, &app), true);
     assert_eq!(queue.should_enqueue_app_used(&turn_1, &app), false);
@@ -3009,11 +3004,7 @@ async fn subagent_tool_items_inherit_parent_connection_metadata() {
 
 #[test]
 fn plugin_used_event_serializes_expected_shape() {
-    let tracking = TrackEventsContext {
-        model_slug: "gpt-5".to_string(),
-        thread_id: "thread-3".to_string(),
-        turn_id: "turn-3".to_string(),
-    };
+    let tracking = test_tracking_context("thread-3", "turn-3");
     let event = TrackEventRequest::PluginUsed(CodexPluginUsedEventRequest {
         event_type: "codex_plugin_used",
         event_params: codex_plugin_used_metadata(&tracking, sample_plugin_metadata()),
@@ -3033,7 +3024,7 @@ fn plugin_used_event_serializes_expected_shape() {
                 "has_skills": true,
                 "mcp_server_count": 2,
                 "connector_ids": ["calendar", "drive"],
-                "product_client_id": originator().value,
+                "product_client_id": TEST_PRODUCT_CLIENT_ID,
                 "mcp_server_names": ["mcp-1", "mcp-2"],
                 "thread_id": "thread-3",
                 "turn_id": "turn-3",
@@ -3132,11 +3123,7 @@ fn plugin_management_event_keeps_plugin_id_local_when_remote_id_exists() {
 
 #[test]
 fn hook_run_event_serializes_expected_shape() {
-    let tracking = TrackEventsContext {
-        model_slug: "gpt-5".to_string(),
-        thread_id: "thread-3".to_string(),
-        turn_id: "turn-3".to_string(),
-    };
+    let tracking = test_tracking_context("thread-3", "turn-3");
     let event = TrackEventRequest::HookRun(CodexHookRunEventRequest {
         event_type: "codex_hook_run",
         event_params: codex_hook_run_metadata(
@@ -3158,6 +3145,7 @@ fn hook_run_event_serializes_expected_shape() {
             "event_params": {
                 "thread_id": "thread-3",
                 "turn_id": "turn-3",
+                "product_client_id": TEST_PRODUCT_CLIENT_ID,
                 "model_slug": "gpt-5",
                 "hook_name": "PreToolUse",
                 "hook_source": "user",
@@ -3169,11 +3157,7 @@ fn hook_run_event_serializes_expected_shape() {
 
 #[test]
 fn hook_run_metadata_maps_sources_and_statuses() {
-    let tracking = TrackEventsContext {
-        model_slug: "gpt-5".to_string(),
-        thread_id: "thread-1".to_string(),
-        turn_id: "turn-1".to_string(),
-    };
+    let tracking = test_tracking_context("thread-1", "turn-1");
 
     let system = serde_json::to_value(codex_hook_run_metadata(
         &tracking,
@@ -3224,11 +3208,7 @@ fn hook_run_metadata_maps_sources_and_statuses() {
 
 #[test]
 fn hook_run_metadata_maps_stopped_status() {
-    let tracking = TrackEventsContext {
-        model_slug: "gpt-5".to_string(),
-        thread_id: "thread-1".to_string(),
-        turn_id: "turn-1".to_string(),
-    };
+    let tracking = test_tracking_context("thread-1", "turn-1");
 
     let stopped = serde_json::to_value(codex_hook_run_metadata(
         &tracking,
@@ -3254,16 +3234,8 @@ fn plugin_used_dedupe_is_keyed_by_turn_and_plugin() {
     };
     let plugin = sample_plugin_metadata();
 
-    let turn_1 = TrackEventsContext {
-        model_slug: "gpt-5".to_string(),
-        thread_id: "thread-1".to_string(),
-        turn_id: "turn-1".to_string(),
-    };
-    let turn_2 = TrackEventsContext {
-        model_slug: "gpt-5".to_string(),
-        thread_id: "thread-1".to_string(),
-        turn_id: "turn-2".to_string(),
-    };
+    let turn_1 = test_tracking_context("thread-1", "turn-1");
+    let turn_2 = test_tracking_context("thread-1", "turn-2");
 
     assert_eq!(queue.should_enqueue_plugin_used(&turn_1, &plugin), true);
     assert_eq!(queue.should_enqueue_plugin_used(&turn_1, &plugin), false);
@@ -3274,11 +3246,7 @@ fn plugin_used_dedupe_is_keyed_by_turn_and_plugin() {
 async fn reducer_ingests_skill_invoked_fact() {
     let mut reducer = AnalyticsReducer::default();
     let mut events = Vec::new();
-    let tracking = TrackEventsContext {
-        model_slug: "gpt-5".to_string(),
-        thread_id: "thread-1".to_string(),
-        turn_id: "turn-1".to_string(),
-    };
+    let tracking = test_tracking_context("thread-1", "turn-1");
     let skill_path = PathBuf::from("/Users/abc/.codex/skills/doc/SKILL.md");
     let expected_skill_id = skill_id_for_local_skill(
         /*repo_url*/ None,
@@ -3311,7 +3279,7 @@ async fn reducer_ingests_skill_invoked_fact() {
             "skill_id": expected_skill_id,
             "skill_name": "doc",
             "event_params": {
-                "product_client_id": originator().value,
+                "product_client_id": TEST_PRODUCT_CLIENT_ID,
                 "skill_scope": "user",
                 "plugin_id": null,
                 "repo_url": null,
@@ -3328,11 +3296,7 @@ async fn reducer_ingests_skill_invoked_fact() {
 async fn reducer_includes_plugin_id_for_plugin_skill_invocations() {
     let mut reducer = AnalyticsReducer::default();
     let mut events = Vec::new();
-    let tracking = TrackEventsContext {
-        model_slug: "gpt-5".to_string(),
-        thread_id: "thread-1".to_string(),
-        turn_id: "turn-1".to_string(),
-    };
+    let tracking = test_tracking_context("thread-1", "turn-1");
     let skill_path =
         PathBuf::from("/Users/abc/.codex/plugins/cache/test/sample/skills/doc/SKILL.md");
 
@@ -3367,11 +3331,7 @@ async fn reducer_ingests_hook_run_fact() {
     reducer
         .ingest(
             AnalyticsFact::Custom(CustomAnalyticsFact::HookRun(HookRunInput {
-                tracking: TrackEventsContext {
-                    model_slug: "gpt-5".to_string(),
-                    thread_id: "thread-1".to_string(),
-                    turn_id: "turn-1".to_string(),
-                },
+                tracking: test_tracking_context("thread-1", "turn-1"),
                 hook: HookRunFact {
                     event_name: HookEventName::PostToolUse,
                     hook_source: HookSource::Unknown,
@@ -3394,11 +3354,7 @@ async fn reducer_ingests_hook_run_fact() {
 async fn reducer_ingests_app_and_plugin_facts() {
     let mut reducer = AnalyticsReducer::default();
     let mut events = Vec::new();
-    let tracking = TrackEventsContext {
-        model_slug: "gpt-5".to_string(),
-        thread_id: "thread-1".to_string(),
-        turn_id: "turn-1".to_string(),
-    };
+    let tracking = test_tracking_context("thread-1", "turn-1");
 
     reducer
         .ingest(
@@ -3441,6 +3397,18 @@ async fn reducer_ingests_app_and_plugin_facts() {
     assert_eq!(payload[0]["event_type"], "codex_app_mentioned");
     assert_eq!(payload[1]["event_type"], "codex_app_used");
     assert_eq!(payload[2]["event_type"], "codex_plugin_used");
+    assert_eq!(
+        payload[0]["event_params"]["product_client_id"],
+        TEST_PRODUCT_CLIENT_ID
+    );
+    assert_eq!(
+        payload[1]["event_params"]["product_client_id"],
+        TEST_PRODUCT_CLIENT_ID
+    );
+    assert_eq!(
+        payload[2]["event_params"]["product_client_id"],
+        TEST_PRODUCT_CLIENT_ID
+    );
 }
 
 #[tokio::test]
diff --git a/codex-rs/analytics/src/events.rs b/codex-rs/analytics/src/events.rs
index 2fe465c9b..1365e5406 100644
--- a/codex-rs/analytics/src/events.rs
+++ b/codex-rs/analytics/src/events.rs
@@ -773,6 +773,7 @@ pub(crate) struct CodexAppUsedEventRequest {
 pub(crate) struct CodexHookRunMetadata {
     pub(crate) thread_id: Option<String>,
     pub(crate) turn_id: Option<String>,
+    pub(crate) product_client_id: Option<String>,
     pub(crate) model_slug: Option<String>,
     pub(crate) hook_name: Option<String>,
     pub(crate) hook_source: Option<&'static str>,
@@ -1030,13 +1031,20 @@ pub(crate) fn codex_app_metadata(
         thread_id: Some(tracking.thread_id.clone()),
         turn_id: Some(tracking.turn_id.clone()),
         app_name: app.app_name,
-        product_client_id: Some(originator().value),
+        product_client_id: Some(tracking.product_client_id.clone()),
         invoke_type: app.invocation_type,
         model_slug: Some(tracking.model_slug.clone()),
     }
 }
 
 pub(crate) fn codex_plugin_metadata(plugin: PluginTelemetryMetadata) -> CodexPluginMetadata {
+    codex_plugin_metadata_with_product_client_id(plugin, originator().value)
+}
+
+fn codex_plugin_metadata_with_product_client_id(
+    plugin: PluginTelemetryMetadata,
+    product_client_id: String,
+) -> CodexPluginMetadata {
     let PluginTelemetryMetadata {
         plugin_id,
         remote_plugin_id,
@@ -1062,7 +1070,7 @@ pub(crate) fn codex_plugin_metadata(plugin: PluginTelemetryMetadata) -> CodexPlu
                 .map(|connector_id| connector_id.0)
                 .collect()
         }),
-        product_client_id: Some(originator().value),
+        product_client_id: Some(product_client_id),
     }
 }
 
@@ -1139,7 +1147,10 @@ pub(crate) fn codex_plugin_used_metadata(
         .as_ref()
         .map(|summary| summary.mcp_server_names.clone());
     CodexPluginUsedMetadata {
-        plugin: codex_plugin_metadata(plugin),
+        plugin: codex_plugin_metadata_with_product_client_id(
+            plugin,
+            tracking.product_client_id.clone(),
+        ),
         mcp_server_names,
         thread_id: Some(tracking.thread_id.clone()),
         turn_id: Some(tracking.turn_id.clone()),
@@ -1154,6 +1165,7 @@ pub(crate) fn codex_hook_run_metadata(
     CodexHookRunMetadata {
         thread_id: Some(tracking.thread_id.clone()),
         turn_id: Some(tracking.turn_id.clone()),
+        product_client_id: Some(tracking.product_client_id.clone()),
         model_slug: Some(tracking.model_slug.clone()),
         hook_name: Some(analytics_hook_event_name(hook.event_name).to_owned()),
         hook_source: Some(analytics_hook_source(hook.hook_source)),
diff --git a/codex-rs/analytics/src/facts.rs b/codex-rs/analytics/src/facts.rs
index 026c2e876..4505c0c69 100644
--- a/codex-rs/analytics/src/facts.rs
+++ b/codex-rs/analytics/src/facts.rs
@@ -41,17 +41,20 @@ pub struct TrackEventsContext {
     pub model_slug: String,
     pub thread_id: String,
     pub turn_id: String,
+    pub product_client_id: String,
 }
 
 pub fn build_track_events_context(
     model_slug: String,
     thread_id: String,
     turn_id: String,
+    product_client_id: String,
 ) -> TrackEventsContext {
     TrackEventsContext {
         model_slug,
         thread_id,
         turn_id,
+        product_client_id,
     }
 }
 
diff --git a/codex-rs/analytics/src/reducer.rs b/codex-rs/analytics/src/reducer.rs
index b647984df..666e756d3 100644
--- a/codex-rs/analytics/src/reducer.rs
+++ b/codex-rs/analytics/src/reducer.rs
@@ -729,7 +729,7 @@ impl AnalyticsReducer {
                         turn_id: Some(tracking.turn_id.clone()),
                         invoke_type: Some(invocation.invocation_type),
                         model_slug: Some(tracking.model_slug.clone()),
-                        product_client_id: Some(originator().value),
+                        product_client_id: Some(tracking.product_client_id.clone()),
                         repo_url,
                         skill_scope: Some(skill_scope.to_string()),
                         plugin_id: invocation.plugin_id,
diff --git a/codex-rs/app-server/src/request_processors/external_agent_session_import.rs b/codex-rs/app-server/src/request_processors/external_agent_session_import.rs
index dfa2ea94f..77b9bfcbf 100644
--- a/codex-rs/app-server/src/request_processors/external_agent_session_import.rs
+++ b/codex-rs/app-server/src/request_processors/external_agent_session_import.rs
@@ -207,6 +207,7 @@ impl ExternalAgentSessionImporter {
             parent_thread_id: None,
             source: source.clone(),
             thread_source: None,
+            originator: codex_login::default_client::originator().value,
             base_instructions: BaseInstructions {
                 text: config
                     .base_instructions
diff --git a/codex-rs/app-server/src/request_processors/thread_processor_tests.rs b/codex-rs/app-server/src/request_processors/thread_processor_tests.rs
index 1f5ae12f4..3f7cbc9d0 100644
--- a/codex-rs/app-server/src/request_processors/thread_processor_tests.rs
+++ b/codex-rs/app-server/src/request_processors/thread_processor_tests.rs
@@ -781,6 +781,7 @@ mod thread_processor_behavior_tests {
             forked_from_thread_id: None,
             parent_thread_id: None,
             thread_source: None,
+            originator: "test_originator".to_string(),
         };
 
         assert_eq!(
diff --git a/codex-rs/app-server/tests/suite/conversation_summary.rs b/codex-rs/app-server/tests/suite/conversation_summary.rs
index d4d0cf061..7f964d314 100644
--- a/codex-rs/app-server/tests/suite/conversation_summary.rs
+++ b/codex-rs/app-server/tests/suite/conversation_summary.rs
@@ -128,6 +128,7 @@ async fn get_conversation_summary_by_thread_id_reads_pathless_store_thread() ->
             parent_thread_id: None,
             source: SessionSource::Cli,
             thread_source: None,
+            originator: "test_originator".to_string(),
             base_instructions: BaseInstructions::default(),
             dynamic_tools: Vec::new(),
             multi_agent_version: None,
diff --git a/codex-rs/app-server/tests/suite/v2/remote_thread_store.rs b/codex-rs/app-server/tests/suite/v2/remote_thread_store.rs
index 1a6d1eb4f..717fe228f 100644
--- a/codex-rs/app-server/tests/suite/v2/remote_thread_store.rs
+++ b/codex-rs/app-server/tests/suite/v2/remote_thread_store.rs
@@ -154,6 +154,7 @@ async fn thread_delete_with_non_local_thread_store_does_not_create_local_persist
             parent_thread_id: None,
             source: SessionSource::Cli,
             thread_source: None,
+            originator: "test_originator".to_string(),
             base_instructions: BaseInstructions::default(),
             dynamic_tools: Vec::new(),
             multi_agent_version: None,
diff --git a/codex-rs/app-server/tests/suite/v2/thread_read.rs b/codex-rs/app-server/tests/suite/v2/thread_read.rs
index 0b4f101c0..3e39070a7 100644
--- a/codex-rs/app-server/tests/suite/v2/thread_read.rs
+++ b/codex-rs/app-server/tests/suite/v2/thread_read.rs
@@ -1364,6 +1364,7 @@ async fn seed_pathless_store_thread(
             parent_thread_id: None,
             source: ProtocolSessionSource::Cli,
             thread_source: None,
+            originator: "test_originator".to_string(),
             base_instructions: BaseInstructions::default(),
             dynamic_tools: Vec::new(),
             multi_agent_version: None,
diff --git a/codex-rs/app-server/tests/suite/v2/thread_unarchive.rs b/codex-rs/app-server/tests/suite/v2/thread_unarchive.rs
index db8b60d16..708d4bdfb 100644
--- a/codex-rs/app-server/tests/suite/v2/thread_unarchive.rs
+++ b/codex-rs/app-server/tests/suite/v2/thread_unarchive.rs
@@ -215,6 +215,7 @@ async fn thread_unarchive_preserves_pathless_store_metadata() -> Result<()> {
             parent_thread_id: None,
             source: SessionSource::Cli,
             thread_source: None,
+            originator: "test_originator".to_string(),
             base_instructions: BaseInstructions::default(),
             dynamic_tools: Vec::new(),
             multi_agent_version: None,
diff --git a/codex-rs/core/src/agent/control_tests.rs b/codex-rs/core/src/agent/control_tests.rs
index e37e9b04d..225fd4ba9 100644
--- a/codex-rs/core/src/agent/control_tests.rs
+++ b/codex-rs/core/src/agent/control_tests.rs
@@ -9,7 +9,9 @@ use crate::config::ConfigBuilder;
 use crate::context::ContextualUserFragment;
 use crate::context::SubagentNotification;
 use crate::init_state_db;
+use crate::thread_manager::StartThreadOptions;
 use assert_matches::assert_matches;
+use codex_extension_api::ExtensionDataInit;
 use codex_features::Feature;
 use codex_login::CodexAuth;
 use codex_protocol::AgentPath;
@@ -21,7 +23,9 @@ use codex_protocol::models::ResponseItem;
 use codex_protocol::protocol::CompactedItem;
 use codex_protocol::protocol::ErrorEvent;
 use codex_protocol::protocol::EventMsg;
+use codex_protocol::protocol::InitialHistory;
 use codex_protocol::protocol::InterAgentCommunication;
+use codex_protocol::protocol::RolloutItem;
 use codex_protocol::protocol::SessionSource;
 use codex_protocol::protocol::SubAgentSource;
 use codex_protocol::protocol::TurnAbortReason;
@@ -139,6 +143,33 @@ impl AgentControlHarness {
     }
 }
 
+async fn persisted_originator(thread: &CodexThread) -> String {
+    thread.ensure_rollout_materialized().await;
+    thread
+        .flush_rollout()
+        .await
+        .expect("thread rollout should flush");
+    let stored_thread = thread
+        .read_thread(
+            /*include_archived*/ true, /*include_history*/ true,
+        )
+        .await
+        .expect("thread should be readable");
+    let history = stored_thread.history.expect("history should be loaded");
+    history
+        .items
+        .iter()
+        .find_map(|item| match item {
+            RolloutItem::SessionMeta(meta_line) => Some(meta_line.meta.originator.clone()),
+            RolloutItem::ResponseItem(_)
+            | RolloutItem::InterAgentCommunication(_)
+            | RolloutItem::EventMsg(_)
+            | RolloutItem::Compacted(_)
+            | RolloutItem::TurnContext(_) => None,
+        })
+        .expect("session metadata should be persisted")
+}
+
 fn has_subagent_notification(history_items: &[ResponseItem]) -> bool {
     history_items.iter().any(|item| {
         let ResponseItem::Message { role, content, .. } = item else {
@@ -2199,6 +2230,83 @@ async fn spawn_thread_subagent_gets_random_nickname_in_session_source() {
     assert_eq!(agent_role, Some("explorer".to_string()));
 }
 
+#[tokio::test]
+async fn spawn_thread_subagents_persist_parent_originator_across_new_and_truncated_fork() {
+    let harness = AgentControlHarness::new().await;
+    let parent = harness
+        .manager
+        .start_thread_with_options(StartThreadOptions {
+            config: harness.config.clone(),
+            initial_history: InitialHistory::New,
+            session_source: None,
+            thread_source: None,
+            dynamic_tools: Vec::new(),
+            metrics_service_name: Some("codex_work_desktop".to_string()),
+            multi_agent_mode: None,
+            parent_trace: None,
+            environments: Vec::new(),
+            thread_extension_init: ExtensionDataInit::default(),
+            supports_openai_form_elicitation: false,
+        })
+        .await
+        .expect("parent thread should start");
+    let parent_originator = persisted_originator(&parent.thread).await;
+    assert_eq!(parent_originator, "codex_work_desktop");
+
+    let child_thread_id = harness
+        .control
+        .spawn_agent(
+            harness.config.clone(),
+            text_input("hello child"),
+            Some(SessionSource::SubAgent(SubAgentSource::ThreadSpawn {
+                parent_thread_id: parent.thread_id,
+                depth: 1,
+                agent_path: None,
+                agent_nickname: None,
+                agent_role: Some("explorer".to_string()),
+            })),
+        )
+        .await
+        .expect("child spawn should succeed");
+
+    let child_thread = harness
+        .manager
+        .get_thread(child_thread_id)
+        .await
+        .expect("child thread should be registered");
+    let child_originator = persisted_originator(&child_thread).await;
+    assert_eq!(child_originator, parent_originator);
+
+    let child = harness
+        .control
+        .spawn_agent_with_metadata(
+            harness.config.clone(),
+            text_input("hello forked child"),
+            Some(SessionSource::SubAgent(SubAgentSource::ThreadSpawn {
+                parent_thread_id: parent.thread_id,
+                depth: 1,
+                agent_path: None,
+                agent_nickname: None,
+                agent_role: Some("explorer".to_string()),
+            })),
+            SpawnAgentOptions {
+                fork_parent_spawn_call_id: Some("spawn-call-last-n".to_string()),
+                fork_mode: Some(SpawnAgentForkMode::LastNTurns(1)),
+                ..Default::default()
+            },
+        )
+        .await
+        .expect("forked child spawn should succeed");
+
+    let child_thread = harness
+        .manager
+        .get_thread(child.thread_id)
+        .await
+        .expect("child thread should be registered");
+    let child_originator = persisted_originator(&child_thread).await;
+    assert_eq!(child_originator, parent_originator);
+}
+
 #[tokio::test]
 async fn spawn_thread_subagent_uses_role_specific_nickname_candidates() {
     let mut harness = AgentControlHarness::new().await;
diff --git a/codex-rs/core/src/client.rs b/codex-rs/core/src/client.rs
index 9e240e968..67a940dc9 100644
--- a/codex-rs/core/src/client.rs
+++ b/codex-rs/core/src/client.rs
@@ -186,6 +186,7 @@ struct ModelClientState {
     provider: SharedModelProvider,
     auth_env_telemetry: AuthEnvTelemetry,
     session_source: SessionSource,
+    originator: String,
     model_verbosity: Option<VerbosityConfig>,
     enable_request_compression: bool,
     include_timing_metrics: bool,
@@ -387,6 +388,7 @@ impl ModelClient {
         thread_id: ThreadId,
         provider_info: ModelProviderInfo,
         session_source: SessionSource,
+        originator: String,
         model_verbosity: Option<VerbosityConfig>,
         enable_request_compression: bool,
         include_timing_metrics: bool,
@@ -408,6 +410,7 @@ impl ModelClient {
                 provider: model_provider,
                 auth_env_telemetry,
                 session_source,
+                originator,
                 model_verbosity,
                 enable_request_compression,
                 include_timing_metrics,
@@ -565,6 +568,7 @@ impl ModelClient {
             self.state.beta_features_header.as_deref(),
             turn_state.as_ref(),
         ));
+        add_originator_header(&mut extra_headers, self.state.originator.as_str());
         extra_headers.extend(self.build_responses_compatibility_headers(responses_metadata));
         extra_headers.extend(build_session_headers(
             Some(responses_metadata.session_id.to_string()),
@@ -676,6 +680,7 @@ impl ModelClient {
 
     fn build_subagent_headers(&self) -> ApiHeaderMap {
         let mut extra_headers = ApiHeaderMap::new();
+        add_originator_header(&mut extra_headers, self.state.originator.as_str());
         if let Some(subagent) = subagent_header_value(&self.state.session_source)
             && let Ok(val) = HeaderValue::from_str(&subagent)
         {
@@ -997,6 +1002,7 @@ impl ModelClient {
             self.state.beta_features_header.as_deref(),
             /*turn_state*/ None,
         );
+        add_originator_header(&mut headers, self.state.originator.as_str());
         if let Ok(header_value) = HeaderValue::from_str(&responses_metadata.thread_id) {
             headers.insert("x-client-request-id", header_value);
         }
@@ -1064,6 +1070,7 @@ impl ModelClientSession {
                     self.client.state.beta_features_header.as_deref(),
                     Some(&self.turn_state),
                 );
+                add_originator_header(&mut headers, self.client.state.originator.as_str());
                 headers.extend(
                     self.client
                         .build_responses_compatibility_headers(responses_metadata),
@@ -1791,6 +1798,22 @@ fn build_responses_headers(
     headers
 }
 
+pub(crate) fn add_originator_header(headers: &mut ApiHeaderMap, originator: &str) {
+    let default_originator = codex_login::default_client::originator();
+    if originator == default_originator.value.as_str() {
+        return;
+    }
+
+    match HeaderValue::from_str(originator) {
+        Ok(header_value) => {
+            headers.insert("originator", header_value);
+        }
+        Err(err) => {
+            warn!("ignoring invalid thread originator header value: {err}");
+        }
+    }
+}
+
 fn add_responses_lite_header(headers: &mut ApiHeaderMap, use_responses_lite: bool) {
     if use_responses_lite {
         headers.insert(
diff --git a/codex-rs/core/src/client_tests.rs b/codex-rs/core/src/client_tests.rs
index 9df7d4d01..8d58fec9b 100644
--- a/codex-rs/core/src/client_tests.rs
+++ b/codex-rs/core/src/client_tests.rs
@@ -75,6 +75,7 @@ fn test_model_client(session_source: SessionSource) -> ModelClient {
         thread_id,
         provider,
         session_source,
+        "test_originator".to_string(),
         /*model_verbosity*/ None,
         /*enable_request_compression*/ false,
         /*include_timing_metrics*/ false,
@@ -298,6 +299,10 @@ fn build_subagent_headers_sets_internal_memory_consolidation_label() {
         .get(X_OPENAI_SUBAGENT_HEADER)
         .and_then(|value| value.to_str().ok());
     assert_eq!(value, Some("memory_consolidation"));
+    assert_eq!(
+        headers.get("originator"),
+        Some(&http::HeaderValue::from_static("test_originator"))
+    );
 }
 
 #[test]
@@ -606,6 +611,7 @@ fn model_client_with_counting_attestation(
         ThreadId::new(),
         provider,
         SessionSource::Exec,
+        "test_originator".to_string(),
         /*model_verbosity*/ None,
         /*enable_request_compression*/ false,
         /*include_timing_metrics*/ false,
diff --git a/codex-rs/core/src/codex_delegate.rs b/codex-rs/core/src/codex_delegate.rs
index 9f5b867f7..640e1f8df 100644
--- a/codex-rs/core/src/codex_delegate.rs
+++ b/codex-rs/core/src/codex_delegate.rs
@@ -103,6 +103,7 @@ pub(crate) async fn run_codex_thread_interactive(
         forked_from_thread_id,
         parent_thread_id: Some(parent_session.thread_id),
         thread_source: Some(ThreadSource::Subagent),
+        originator: parent_ctx.originator.clone(),
         agent_control: parent_session.services.agent_control.clone(),
         dynamic_tools: Vec::new(),
         metrics_service_name: None,
diff --git a/codex-rs/core/src/codex_thread.rs b/codex-rs/core/src/codex_thread.rs
index a522cd62a..dccfd4a76 100644
--- a/codex-rs/core/src/codex_thread.rs
+++ b/codex-rs/core/src/codex_thread.rs
@@ -77,6 +77,7 @@ pub struct ThreadConfigSnapshot {
     pub forked_from_thread_id: Option<ThreadId>,
     pub parent_thread_id: Option<ThreadId>,
     pub thread_source: Option<ThreadSource>,
+    pub originator: String,
 }
 
 /// Explains why `CodexThread::try_start_turn_if_idle` rejected an automatic
diff --git a/codex-rs/core/src/hook_runtime.rs b/codex-rs/core/src/hook_runtime.rs
index 12627e2d5..342e4d4b8 100644
--- a/codex-rs/core/src/hook_runtime.rs
+++ b/codex-rs/core/src/hook_runtime.rs
@@ -685,6 +685,7 @@ fn hook_run_analytics_payload(
                 .turn_id
                 .clone()
                 .unwrap_or_else(|| turn_context.sub_id.clone()),
+            turn_context.originator.clone(),
         ),
         HookRunFact {
             event_name: completed.run.event_name,
diff --git a/codex-rs/core/src/mcp_tool_call.rs b/codex-rs/core/src/mcp_tool_call.rs
index c7187c18f..085fd496d 100644
--- a/codex-rs/core/src/mcp_tool_call.rs
+++ b/codex-rs/core/src/mcp_tool_call.rs
@@ -971,6 +971,7 @@ async fn maybe_track_codex_app_used(
         turn_context.model_info.slug.clone(),
         sess.thread_id.to_string(),
         turn_context.sub_id.clone(),
+        turn_context.originator.clone(),
     );
     sess.services.analytics_events_client.track_app_used(
         tracking,
diff --git a/codex-rs/core/src/realtime_conversation.rs b/codex-rs/core/src/realtime_conversation.rs
index 667939f10..43ecc3e57 100644
--- a/codex-rs/core/src/realtime_conversation.rs
+++ b/codex-rs/core/src/realtime_conversation.rs
@@ -1,4 +1,5 @@
 use crate::client::ModelClient;
+use crate::client::add_originator_header;
 use crate::realtime_context::build_realtime_startup_context;
 use crate::realtime_context::truncate_realtime_text_to_token_budget;
 use crate::realtime_prompt::prepare_realtime_backend_prompt;
@@ -775,6 +776,7 @@ async fn prepare_realtime_start(
     let session_config =
         build_realtime_session_config(sess, &params, version, configured_voice).await?;
     let requested_realtime_session_id = session_config.session_id.clone();
+    let originator = sess.originator().await;
     let extra_headers = match transport {
         ConversationStartTransport::Websocket => {
             let realtime_api_key = realtime_api_key(auth.as_ref(), &provider)?;
@@ -782,6 +784,7 @@ async fn prepare_realtime_start(
                 requested_realtime_session_id.as_deref(),
                 Some(realtime_api_key.as_str()),
                 version,
+                originator.as_str(),
             )?
         }
         ConversationStartTransport::Webrtc { .. } => {
@@ -789,6 +792,7 @@ async fn prepare_realtime_start(
                 requested_realtime_session_id.as_deref(),
                 /*api_key*/ None,
                 version,
+                originator.as_str(),
             )?
         }
     };
@@ -1171,6 +1175,7 @@ fn realtime_request_headers(
     realtime_session_id: Option<&str>,
     api_key: Option<&str>,
     version: RealtimeWsVersion,
+    originator: &str,
 ) -> CodexResult<Option<HeaderMap>> {
     let mut headers = HeaderMap::new();
 
@@ -1191,6 +1196,8 @@ fn realtime_request_headers(
         headers.insert(AUTHORIZATION, auth_value);
     }
 
+    add_originator_header(&mut headers, originator);
+
     Ok(Some(headers))
 }
 
diff --git a/codex-rs/core/src/realtime_conversation_tests.rs b/codex-rs/core/src/realtime_conversation_tests.rs
index 55525774b..51425e4c3 100644
--- a/codex-rs/core/src/realtime_conversation_tests.rs
+++ b/codex-rs/core/src/realtime_conversation_tests.rs
@@ -149,10 +149,14 @@ async fn clears_active_handoff_explicitly() {
 
 #[test]
 fn uses_quicksilver_alpha_header_for_realtime_v1() {
-    let headers =
-        realtime_request_headers(Some("session_1"), Some("sk-test"), RealtimeWsVersion::V1)
-            .expect("headers")
-            .expect("headers");
+    let headers = realtime_request_headers(
+        Some("session_1"),
+        Some("sk-test"),
+        RealtimeWsVersion::V1,
+        "codex_work_desktop",
+    )
+    .expect("headers")
+    .expect("headers");
 
     assert_eq!(
         headers
@@ -164,10 +168,39 @@ fn uses_quicksilver_alpha_header_for_realtime_v1() {
 
 #[test]
 fn omits_quicksilver_alpha_header_for_realtime_v2() {
-    let headers =
-        realtime_request_headers(Some("session_1"), Some("sk-test"), RealtimeWsVersion::V2)
-            .expect("headers")
-            .expect("headers");
+    let headers = realtime_request_headers(
+        Some("session_1"),
+        Some("sk-test"),
+        RealtimeWsVersion::V2,
+        "codex_work_desktop",
+    )
+    .expect("headers")
+    .expect("headers");
 
     assert!(headers.get("openai-alpha").is_none());
 }
+
+#[test]
+fn realtime_headers_include_only_non_default_originator() {
+    let default_originator = codex_login::default_client::originator();
+    for (originator, expected_header) in [
+        ("codex_work_desktop", Some("codex_work_desktop")),
+        (default_originator.value.as_str(), None),
+    ] {
+        let headers = realtime_request_headers(
+            Some("session_1"),
+            Some("sk-test"),
+            RealtimeWsVersion::V2,
+            originator,
+        )
+        .expect("headers")
+        .expect("headers");
+
+        assert_eq!(
+            headers
+                .get("originator")
+                .and_then(|value| value.to_str().ok()),
+            expected_header
+        );
+    }
+}
diff --git a/codex-rs/core/src/session/mod.rs b/codex-rs/core/src/session/mod.rs
index d94ca7f34..9db1df044 100644
--- a/codex-rs/core/src/session/mod.rs
+++ b/codex-rs/core/src/session/mod.rs
@@ -73,7 +73,6 @@ use codex_hooks::HooksConfig;
 use codex_login::AuthManager;
 use codex_login::CodexAuth;
 use codex_login::auth_env_telemetry::collect_auth_env_telemetry;
-use codex_login::default_client::originator;
 use codex_mcp::McpConnectionManager;
 use codex_mcp::McpResourceClient;
 use codex_mcp::McpRuntimeContext;
@@ -433,6 +432,7 @@ pub(crate) struct CodexSpawnArgs {
     pub(crate) forked_from_thread_id: Option<ThreadId>,
     pub(crate) parent_thread_id: Option<ThreadId>,
     pub(crate) thread_source: Option<ThreadSource>,
+    pub(crate) originator: String,
     pub(crate) agent_control: AgentControl,
     pub(crate) dynamic_tools: Vec<DynamicToolSpec>,
     pub(crate) metrics_service_name: Option<String>,
@@ -522,6 +522,7 @@ impl Codex {
             forked_from_thread_id,
             parent_thread_id,
             thread_source,
+            originator,
             agent_control,
             dynamic_tools,
             metrics_service_name,
@@ -654,6 +655,7 @@ impl Codex {
             forked_from_thread_id,
             parent_thread_id,
             thread_source,
+            originator,
             dynamic_tools,
             user_shell_override,
         };
@@ -3913,7 +3915,7 @@ pub(crate) fn emit_subagent_session_started(
         forked_from_thread_id: thread_config
             .forked_from_thread_id
             .map(|thread_id| thread_id.to_string()),
-        product_client_id: client_name.clone(),
+        product_client_id: thread_config.originator.clone(),
         client_name,
         client_version,
         model: thread_config.model,
diff --git a/codex-rs/core/src/session/review.rs b/codex-rs/core/src/session/review.rs
index 8986ffd05..c55afbf14 100644
--- a/codex-rs/core/src/session/review.rs
+++ b/codex-rs/core/src/session/review.rs
@@ -118,6 +118,7 @@ pub(super) async fn spawn_review_thread(
         reasoning_summary,
         session_source,
         parent_thread_id: parent_turn_context.parent_thread_id,
+        originator: parent_turn_context.originator.clone(),
         environments: parent_turn_context.environments.clone(),
         available_models,
         unified_exec_shell_mode,
diff --git a/codex-rs/core/src/session/session.rs b/codex-rs/core/src/session/session.rs
index ee62155a8..af64e0bef 100644
--- a/codex-rs/core/src/session/session.rs
+++ b/codex-rs/core/src/session/session.rs
@@ -106,6 +106,8 @@ pub(crate) struct SessionConfiguration {
     pub(super) parent_thread_id: Option<ThreadId>,
     /// Optional analytics source classification for this thread.
     pub(super) thread_source: Option<ThreadSource>,
+    /// Effective originator used for this thread's Responses requests and analytics events.
+    pub(super) originator: String,
     pub(super) dynamic_tools: Vec<DynamicToolSpec>,
     pub(super) user_shell_override: Option<shell::Shell>,
 }
@@ -198,6 +200,7 @@ impl SessionConfiguration {
             forked_from_thread_id: self.forked_from_thread_id,
             parent_thread_id: self.parent_thread_id,
             thread_source: self.thread_source.clone(),
+            originator: self.originator.clone(),
         }
     }
 
@@ -473,6 +476,11 @@ impl Session {
         self.services.agent_control.session_id()
     }
 
+    pub(crate) async fn originator(&self) -> String {
+        let state = self.state.lock().await;
+        state.session_configuration.originator.clone()
+    }
+
     #[instrument(name = "session_init", level = "info", skip_all)]
     #[allow(clippy::too_many_arguments)]
     pub(crate) async fn new(
@@ -581,6 +589,7 @@ impl Session {
                             parent_thread_id,
                             source: session_source,
                             thread_source: session_configuration.thread_source.clone(),
+                            originator: session_configuration.originator.clone(),
                             base_instructions: BaseInstructions {
                                 text: session_configuration.base_instructions.clone(),
                             },
@@ -756,7 +765,7 @@ impl Session {
             let auth_mode = auth.map(CodexAuth::auth_mode).map(TelemetryAuthMode::from);
             let account_id = auth.and_then(CodexAuth::get_account_id);
             let account_email = auth.and_then(CodexAuth::get_account_email);
-            let originator = originator().value;
+            let originator = session_configuration.originator.clone();
             let terminal_type = user_agent();
             let session_model = session_configuration.collaboration_mode.model().to_string();
             let auth_env_telemetry = collect_auth_env_telemetry(
@@ -1057,6 +1066,7 @@ impl Session {
                     thread_id,
                     session_configuration.provider.clone(),
                     session_configuration.session_source.clone(),
+                    session_configuration.originator.clone(),
                     config.model_verbosity,
                     config.features.enabled(Feature::EnableRequestCompression),
                     config.features.enabled(Feature::RuntimeMetrics),
diff --git a/codex-rs/core/src/session/tests.rs b/codex-rs/core/src/session/tests.rs
index 1ebb069f0..685005b40 100644
--- a/codex-rs/core/src/session/tests.rs
+++ b/codex-rs/core/src/session/tests.rs
@@ -479,6 +479,7 @@ fn test_model_client_session() -> crate::client::ModelClientSession {
         thread_id,
         ModelProviderInfo::create_openai_provider(/* base_url */ /*base_url*/ None),
         codex_protocol::protocol::SessionSource::Exec,
+        "test_originator".to_string(),
         /*model_verbosity*/ None,
         /*enable_request_compression*/ false,
         /*include_timing_metrics*/ false,
@@ -3485,6 +3486,7 @@ async fn set_rate_limits_retains_previous_credits() {
         forked_from_thread_id: None,
         parent_thread_id: None,
         thread_source: None,
+        originator: "test_originator".to_string(),
         dynamic_tools: Vec::new(),
         user_shell_override: None,
     };
@@ -3592,6 +3594,7 @@ async fn set_rate_limits_updates_plan_type_when_present() {
         forked_from_thread_id: None,
         parent_thread_id: None,
         thread_source: None,
+        originator: "test_originator".to_string(),
         dynamic_tools: Vec::new(),
         user_shell_override: None,
     };
@@ -3841,6 +3844,7 @@ async fn attach_thread_persistence(session: &mut Session) -> PathBuf {
             parent_thread_id: None,
             source: SessionSource::Exec,
             thread_source: None,
+            originator: "test_originator".to_string(),
             base_instructions: BaseInstructions::default(),
             dynamic_tools: Vec::new(),
             multi_agent_version: None,
@@ -4122,13 +4126,14 @@ pub(crate) async fn make_session_configuration_for_tests() -> SessionConfigurati
         forked_from_thread_id: None,
         parent_thread_id: None,
         thread_source: None,
+        originator: "test_originator".to_string(),
         dynamic_tools: Vec::new(),
         user_shell_override: None,
     }
 }
 
 #[tokio::test]
-async fn emit_subagent_session_started_includes_fork_lineage_from_session_configuration() {
+async fn emit_subagent_session_started_includes_fork_lineage_and_originator() {
     use wiremock::Mock;
     use wiremock::MockServer;
     use wiremock::ResponseTemplate;
@@ -4204,6 +4209,10 @@ async fn emit_subagent_session_started_includes_fork_lineage_from_session_config
         event["event_params"]["forked_from_thread_id"],
         forked_from_thread_id.to_string()
     );
+    assert_eq!(
+        event["event_params"]["app_server_client"]["product_client_id"],
+        "test_originator"
+    );
 }
 
 async fn resolved_environments_for_configuration(
@@ -4989,6 +4998,7 @@ async fn session_new_fails_when_zsh_fork_enabled_without_packaged_zsh() {
         forked_from_thread_id: None,
         parent_thread_id: None,
         thread_source: None,
+        originator: "test_originator".to_string(),
         dynamic_tools: Vec::new(),
         user_shell_override: None,
     };
@@ -5118,6 +5128,7 @@ pub(crate) async fn make_session_and_context() -> (Session, TurnContext) {
         forked_from_thread_id: None,
         parent_thread_id: None,
         thread_source: None,
+        originator: "test_originator".to_string(),
         dynamic_tools: Vec::new(),
         user_shell_override: None,
     };
@@ -5220,6 +5231,7 @@ pub(crate) async fn make_session_and_context() -> (Session, TurnContext) {
             thread_id,
             session_configuration.provider.clone(),
             session_configuration.session_source.clone(),
+            session_configuration.originator.clone(),
             config.model_verbosity,
             config.features.enabled(Feature::EnableRequestCompression),
             config.features.enabled(Feature::RuntimeMetrics),
@@ -5364,6 +5376,7 @@ async fn make_session_with_config_and_rx(
         forked_from_thread_id: None,
         parent_thread_id: None,
         thread_source: None,
+        originator: "test_originator".to_string(),
         dynamic_tools: Vec::new(),
         user_shell_override: None,
     };
@@ -5471,6 +5484,7 @@ async fn make_session_with_history_source_and_agent_control_and_rx(
         forked_from_thread_id: None,
         parent_thread_id: None,
         thread_source: None,
+        originator: "test_originator".to_string(),
         dynamic_tools: Vec::new(),
         user_shell_override: None,
     };
@@ -6713,6 +6727,7 @@ async fn shutdown_complete_does_not_append_to_thread_store_after_shutdown() {
             parent_thread_id: None,
             source: SessionSource::Exec,
             thread_source: None,
+            originator: "test_originator".to_string(),
             base_instructions: BaseInstructions::default(),
             dynamic_tools: Vec::new(),
             multi_agent_version: None,
@@ -7194,6 +7209,7 @@ where
         forked_from_thread_id: None,
         parent_thread_id: None,
         thread_source: None,
+        originator: "test_originator".to_string(),
         dynamic_tools,
         user_shell_override: None,
     };
@@ -7295,6 +7311,7 @@ where
             thread_id,
             session_configuration.provider.clone(),
             session_configuration.session_source.clone(),
+            session_configuration.originator.clone(),
             config.model_verbosity,
             config.features.enabled(Feature::EnableRequestCompression),
             config.features.enabled(Feature::RuntimeMetrics),
diff --git a/codex-rs/core/src/session/tests/guardian_tests.rs b/codex-rs/core/src/session/tests/guardian_tests.rs
index e61578929..6f23cb096 100644
--- a/codex-rs/core/src/session/tests/guardian_tests.rs
+++ b/codex-rs/core/src/session/tests/guardian_tests.rs
@@ -733,6 +733,7 @@ async fn guardian_subagent_does_not_inherit_parent_exec_policy_rules() {
         forked_from_thread_id: None,
         parent_thread_id: None,
         thread_source: None,
+        originator: "test_originator".to_string(),
         agent_control: AgentControl::default(),
         dynamic_tools: Vec::new(),
         metrics_service_name: None,
diff --git a/codex-rs/core/src/session/turn.rs b/codex-rs/core/src/session/turn.rs
index 397dd17b6..42c072dd0 100644
--- a/codex-rs/core/src/session/turn.rs
+++ b/codex-rs/core/src/session/turn.rs
@@ -526,6 +526,7 @@ async fn build_skills_and_plugins(
         turn_context.model_info.slug.clone(),
         sess.thread_id.to_string(),
         turn_context.sub_id.clone(),
+        turn_context.originator.clone(),
     );
     let loaded_plugins = sess
         .services
diff --git a/codex-rs/core/src/session/turn_context.rs b/codex-rs/core/src/session/turn_context.rs
index fdd9df5d5..da526d491 100644
--- a/codex-rs/core/src/session/turn_context.rs
+++ b/codex-rs/core/src/session/turn_context.rs
@@ -113,6 +113,7 @@ pub struct TurnContext {
     pub(crate) reasoning_summary: ReasoningSummaryConfig,
     pub(crate) session_source: SessionSource,
     pub(crate) parent_thread_id: Option<ThreadId>,
+    pub(crate) originator: String,
     pub(crate) environments: TurnEnvironmentSnapshot,
     /// The session's absolute working directory. All relative paths provided
     /// by the model as well as sandbox policies are resolved against this path
@@ -265,6 +266,7 @@ impl TurnContext {
             reasoning_summary: self.reasoning_summary,
             session_source: self.session_source.clone(),
             parent_thread_id: self.parent_thread_id,
+            originator: self.originator.clone(),
             environments: self.environments.clone(),
             #[allow(deprecated)]
             cwd: self.cwd.clone(),
@@ -548,6 +550,7 @@ impl Session {
             reasoning_summary,
             session_source,
             parent_thread_id: session_configuration.parent_thread_id,
+            originator: session_configuration.originator.clone(),
             environments,
             #[allow(deprecated)]
             cwd,
diff --git a/codex-rs/core/src/skills.rs b/codex-rs/core/src/skills.rs
index 2c1ba8245..7b5d87b26 100644
--- a/codex-rs/core/src/skills.rs
+++ b/codex-rs/core/src/skills.rs
@@ -102,6 +102,7 @@ pub(crate) async fn maybe_emit_implicit_skill_invocation(
                 turn_context.model_info.slug.clone(),
                 sess.thread_id.to_string(),
                 turn_context.sub_id.clone(),
+                turn_context.originator.clone(),
             ),
             vec![invocation],
         );
diff --git a/codex-rs/core/src/thread_manager.rs b/codex-rs/core/src/thread_manager.rs
index 816df89c3..75a02d999 100644
--- a/codex-rs/core/src/thread_manager.rs
+++ b/codex-rs/core/src/thread_manager.rs
@@ -29,6 +29,8 @@ use codex_extension_api::empty_extension_registry;
 use codex_features::Feature;
 use codex_login::AuthManager;
 use codex_login::CodexAuth;
+use codex_login::default_client::CODEX_INTERNAL_ORIGINATOR_OVERRIDE_ENV_VAR;
+use codex_login::default_client::originator;
 use codex_model_provider::create_model_provider;
 use codex_model_provider_info::ModelProviderInfo;
 use codex_model_provider_info::OPENAI_PROVIDER_ID;
@@ -192,6 +194,28 @@ pub struct StartThreadOptions {
     pub supports_openai_form_elicitation: bool,
 }
 
+fn originator_from_service_name(service_name: Option<&str>) -> Option<String> {
+    let service_name = service_name?.trim();
+    if service_name.eq_ignore_ascii_case("codex_work_desktop") {
+        return Some("codex_work_desktop".to_string());
+    }
+    None
+}
+
+fn effective_originator_value(
+    metrics_service_name: Option<&str>,
+    env_originator: Option<String>,
+    persisted_originator: Option<String>,
+    inherited_originator: Option<String>,
+    default_originator: String,
+) -> String {
+    originator_from_service_name(metrics_service_name)
+        .or(persisted_originator)
+        .or(inherited_originator)
+        .or(env_originator)
+        .unwrap_or(default_originator)
+}
+
 pub(crate) struct ResumeThreadWithHistoryOptions {
     pub(crate) config: Config,
     pub(crate) initial_history: InitialHistory,
@@ -1220,6 +1244,64 @@ impl ThreadManagerState {
         }
     }
 
+    async fn inherited_originator_for_parent_thread(
+        &self,
+        session_source: &SessionSource,
+        parent_thread_id: Option<ThreadId>,
+        forked_from_thread_id: Option<ThreadId>,
+    ) -> Option<String> {
+        let inherited_thread_id = match session_source {
+            SessionSource::SubAgent(SubAgentSource::ThreadSpawn {
+                parent_thread_id, ..
+            }) => Some(*parent_thread_id),
+            _ => parent_thread_id.or(forked_from_thread_id),
+        };
+        let thread = self.get_thread(inherited_thread_id?).await.ok()?;
+        let originator = thread.config_snapshot().await.originator;
+        (!originator.is_empty()).then_some(originator)
+    }
+
+    async fn effective_originator(
+        &self,
+        initial_history: &InitialHistory,
+        metrics_service_name: Option<&str>,
+        session_source: &SessionSource,
+        parent_thread_id: Option<ThreadId>,
+        forked_from_thread_id: Option<ThreadId>,
+    ) -> String {
+        let persisted_originator = initial_history.get_session_originator();
+        let inherited_originator = match initial_history {
+            InitialHistory::New | InitialHistory::Cleared => {
+                self.inherited_originator_for_parent_thread(
+                    session_source,
+                    parent_thread_id,
+                    forked_from_thread_id,
+                )
+                .await
+            }
+            InitialHistory::Forked(_) if persisted_originator.is_none() => {
+                self.inherited_originator_for_parent_thread(
+                    session_source,
+                    parent_thread_id,
+                    forked_from_thread_id,
+                )
+                .await
+            }
+            InitialHistory::Resumed(_) | InitialHistory::Forked(_) => None,
+        };
+
+        let env_originator = std::env::var(CODEX_INTERNAL_ORIGINATOR_OVERRIDE_ENV_VAR)
+            .is_ok()
+            .then(|| originator().value);
+        effective_originator_value(
+            metrics_service_name,
+            env_originator,
+            persisted_originator,
+            inherited_originator,
+            originator().value,
+        )
+    }
+
     /// Spawn a new thread with no history using a provided config.
     pub(crate) async fn spawn_new_thread(
         &self,
@@ -1466,6 +1548,15 @@ impl ThreadManagerState {
                 forked_from_thread_id,
             )
             .await;
+        let originator = self
+            .effective_originator(
+                &initial_history,
+                metrics_service_name.as_deref(),
+                &session_source,
+                parent_thread_id,
+                forked_from_thread_id,
+            )
+            .await;
         let CodexSpawnOk {
             codex, thread_id, ..
         } = Box::pin(Codex::spawn(CodexSpawnArgs {
@@ -1484,6 +1575,7 @@ impl ThreadManagerState {
             forked_from_thread_id,
             parent_thread_id,
             thread_source,
+            originator,
             agent_control,
             dynamic_tools,
             metrics_service_name,
diff --git a/codex-rs/core/src/thread_manager_tests.rs b/codex-rs/core/src/thread_manager_tests.rs
index 990c5ca5d..e6b222f6b 100644
--- a/codex-rs/core/src/thread_manager_tests.rs
+++ b/codex-rs/core/src/thread_manager_tests.rs
@@ -68,6 +68,41 @@ fn developer_interrupted_marker() -> ResponseItem {
         .expect("developer interrupted marker should be enabled")
 }
 
+#[test]
+fn effective_originator_prefers_thread_scoped_sources_before_env_originator() {
+    for (metrics_service_name, persisted_originator, inherited_originator, expected_originator) in [
+        (
+            Some("codex_work_desktop"),
+            Some("persisted_originator"),
+            Some("inherited_originator"),
+            "codex_work_desktop",
+        ),
+        (
+            None,
+            Some("persisted_originator"),
+            Some("inherited_originator"),
+            "persisted_originator",
+        ),
+        (
+            None,
+            None,
+            Some("inherited_originator"),
+            "inherited_originator",
+        ),
+    ] {
+        assert_eq!(
+            effective_originator_value(
+                metrics_service_name,
+                Some("Codex Desktop".to_string()),
+                persisted_originator.map(str::to_string),
+                inherited_originator.map(str::to_string),
+                "codex_cli_rs".to_string(),
+            ),
+            expected_originator
+        );
+    }
+}
+
 #[test]
 fn truncates_before_requested_user_message() {
     let items = [
diff --git a/codex-rs/core/tests/responses_headers.rs b/codex-rs/core/tests/responses_headers.rs
index 2f323e0dd..7e213991c 100644
--- a/codex-rs/core/tests/responses_headers.rs
+++ b/codex-rs/core/tests/responses_headers.rs
@@ -123,6 +123,7 @@ async fn responses_stream_includes_subagent_header_on_review() {
         thread_id,
         provider.clone(),
         session_source.clone(),
+        "test_originator".to_string(),
         config.model_verbosity,
         /*enable_request_compression*/ false,
         /*include_timing_metrics*/ false,
@@ -255,6 +256,7 @@ async fn responses_stream_includes_subagent_header_on_other() {
         thread_id,
         provider.clone(),
         session_source.clone(),
+        "test_originator".to_string(),
         config.model_verbosity,
         /*enable_request_compression*/ false,
         /*include_timing_metrics*/ false,
@@ -373,6 +375,7 @@ async fn responses_respects_model_info_overrides_from_config() {
         thread_id,
         provider.clone(),
         session_source.clone(),
+        "test_originator".to_string(),
         config.model_verbosity,
         /*enable_request_compression*/ false,
         /*include_timing_metrics*/ false,
diff --git a/codex-rs/core/tests/suite/client.rs b/codex-rs/core/tests/suite/client.rs
index aa2026be1..98303d09b 100644
--- a/codex-rs/core/tests/suite/client.rs
+++ b/codex-rs/core/tests/suite/client.rs
@@ -1223,6 +1223,7 @@ async fn send_provider_auth_request(server: &MockServer, auth: ModelProviderAuth
         thread_id,
         provider,
         SessionSource::Exec,
+        "test_originator".to_string(),
         config.model_verbosity,
         /*enable_request_compression*/ false,
         /*include_timing_metrics*/ false,
@@ -2835,6 +2836,7 @@ async fn azure_responses_request_includes_store_and_reasoning_ids() {
         thread_id,
         provider.clone(),
         SessionSource::Exec,
+        "test_originator".to_string(),
         config.model_verbosity,
         /*enable_request_compression*/ false,
         /*include_timing_metrics*/ false,
diff --git a/codex-rs/core/tests/suite/client_websockets.rs b/codex-rs/core/tests/suite/client_websockets.rs
index d35714ea4..b1b731a08 100755
--- a/codex-rs/core/tests/suite/client_websockets.rs
+++ b/codex-rs/core/tests/suite/client_websockets.rs
@@ -2192,6 +2192,7 @@ async fn websocket_harness_with_provider_options(
         thread_id,
         provider.clone(),
         SessionSource::Exec,
+        "test_originator".to_string(),
         config.model_verbosity,
         /*enable_request_compression*/ false,
         runtime_metrics_enabled,
diff --git a/codex-rs/core/tests/suite/rollout_list_find.rs b/codex-rs/core/tests/suite/rollout_list_find.rs
index 1461c1af3..c8b10b24e 100644
--- a/codex-rs/core/tests/suite/rollout_list_find.rs
+++ b/codex-rs/core/tests/suite/rollout_list_find.rs
@@ -188,6 +188,7 @@ async fn find_locates_rollout_file_written_by_recorder() -> std::io::Result<()>
             /*parent_thread_id*/ None,
             SessionSource::Exec,
             /*thread_source*/ None,
+            "test_originator".to_string(),
             BaseInstructions::default(),
             Vec::new(),
         ),
diff --git a/codex-rs/memories/write/src/runtime.rs b/codex-rs/memories/write/src/runtime.rs
index 0835e1552..bd86d8313 100644
--- a/codex-rs/memories/write/src/runtime.rs
+++ b/codex-rs/memories/write/src/runtime.rs
@@ -75,6 +75,38 @@ pub(crate) struct MemoryStartupContext {
     session_telemetry: SessionTelemetry,
 }
 
+fn build_session_telemetry(
+    auth_manager: &AuthManager,
+    thread_id: ThreadId,
+    config: &Config,
+    source: SessionSource,
+    model: &str,
+    originator: String,
+) -> SessionTelemetry {
+    let auth = auth_manager.auth_cached();
+    let auth = auth.as_ref();
+    let auth_mode = auth.map(CodexAuth::auth_mode).map(TelemetryAuthMode::from);
+    let account_id = auth.and_then(CodexAuth::get_account_id);
+    let account_email = auth.and_then(CodexAuth::get_account_email);
+    let auth_env_telemetry = collect_auth_env_telemetry(
+        &config.model_provider,
+        auth_manager.codex_api_key_env_enabled(),
+    );
+    SessionTelemetry::new(
+        thread_id,
+        model,
+        model,
+        account_id,
+        account_email,
+        auth_mode,
+        originator,
+        config.otel.log_user_prompt,
+        user_agent(),
+        source,
+    )
+    .with_auth_env(auth_env_telemetry.to_otel_metadata())
+}
+
 impl MemoryStartupContext {
     pub(crate) fn new(
         thread_manager: Arc<ThreadManager>,
@@ -129,29 +161,15 @@ impl MemoryStartupContext {
         source: SessionSource,
         provider: SharedModelProvider,
     ) -> Self {
-        let auth = auth_manager.auth_cached();
-        let auth = auth.as_ref();
-        let auth_mode = auth.map(CodexAuth::auth_mode).map(TelemetryAuthMode::from);
-        let account_id = auth.and_then(CodexAuth::get_account_id);
-        let account_email = auth.and_then(CodexAuth::get_account_email);
         let model = config.model.as_deref().unwrap_or("unknown");
-        let auth_env_telemetry = collect_auth_env_telemetry(
-            &config.model_provider,
-            auth_manager.codex_api_key_env_enabled(),
-        );
-        let session_telemetry = SessionTelemetry::new(
+        let session_telemetry = build_session_telemetry(
+            &auth_manager,
             thread_id,
-            model,
-            model,
-            account_id,
-            account_email,
-            auth_mode,
-            originator().value,
-            config.otel.log_user_prompt,
-            user_agent(),
+            config,
             source,
-        )
-        .with_auth_env(auth_env_telemetry.to_otel_metadata());
+            model,
+            originator().value,
+        );
 
         Self {
             thread_id,
@@ -205,10 +223,14 @@ impl MemoryStartupContext {
 
         StageOneRequestContext {
             model_info,
-            session_telemetry: self
-                .session_telemetry
-                .clone()
-                .with_model(model_name, model_name),
+            session_telemetry: build_session_telemetry(
+                &self.auth_manager,
+                self.thread_id,
+                config,
+                config_snapshot.session_source,
+                model_name,
+                config_snapshot.originator,
+            ),
             reasoning_effort: Some(reasoning_effort),
             reasoning_summary,
             service_tier: config_snapshot.service_tier,
@@ -231,6 +253,7 @@ impl MemoryStartupContext {
             self.thread_id,
             config.model_provider.clone(),
             session_source.clone(),
+            config_snapshot.originator,
             config.model_verbosity,
             config.features.enabled(Feature::EnableRequestCompression),
             config.features.enabled(Feature::RuntimeMetrics),
diff --git a/codex-rs/protocol/src/protocol.rs b/codex-rs/protocol/src/protocol.rs
index b625392e5..a5ff55d47 100644
--- a/codex-rs/protocol/src/protocol.rs
+++ b/codex-rs/protocol/src/protocol.rs
@@ -2609,11 +2609,33 @@ impl InitialHistory {
             .and_then(|meta| meta.thread_source.clone())
     }
 
+    pub fn get_session_originator(&self) -> Option<String> {
+        self.get_session_meta()
+            .map(|meta| meta.originator.clone())
+            .filter(|originator| !originator.is_empty())
+    }
+
     pub fn get_resumed_parent_thread_id(&self) -> Option<ThreadId> {
         self.get_resumed_session_meta()
             .and_then(|meta| meta.parent_thread_id)
     }
 
+    fn get_session_meta(&self) -> Option<&SessionMeta> {
+        match self {
+            InitialHistory::New | InitialHistory::Cleared => None,
+            InitialHistory::Resumed(resumed) => {
+                resumed.history.iter().find_map(|item| match item {
+                    RolloutItem::SessionMeta(meta_line) => Some(&meta_line.meta),
+                    _ => None,
+                })
+            }
+            InitialHistory::Forked(items) => items.iter().find_map(|item| match item {
+                RolloutItem::SessionMeta(meta_line) => Some(&meta_line.meta),
+                _ => None,
+            }),
+        }
+    }
+
     fn get_resumed_session_meta(&self) -> Option<&SessionMeta> {
         match self {
             InitialHistory::New | InitialHistory::Cleared | InitialHistory::Forked(_) => None,
diff --git a/codex-rs/rollout/Cargo.toml b/codex-rs/rollout/Cargo.toml
index edc905968..838081bb5 100644
--- a/codex-rs/rollout/Cargo.toml
+++ b/codex-rs/rollout/Cargo.toml
@@ -17,7 +17,6 @@ anyhow = { workspace = true }
 chrono = { workspace = true, features = ["serde"] }
 codex-file-search = { workspace = true }
 codex-git-utils = { workspace = true }
-codex-login = { workspace = true }
 codex-otel = { workspace = true }
 codex-protocol = { workspace = true }
 codex-state = { workspace = true }
diff --git a/codex-rs/rollout/src/lib.rs b/codex-rs/rollout/src/lib.rs
index 804b8ac10..3c103750c 100644
--- a/codex-rs/rollout/src/lib.rs
+++ b/codex-rs/rollout/src/lib.rs
@@ -16,10 +16,6 @@ pub(crate) mod session_index;
 mod sqlite_metrics;
 pub mod state_db;
 
-pub(crate) mod default_client {
-    pub use codex_login::default_client::*;
-}
-
 pub(crate) use codex_protocol::protocol;
 
 pub const SESSIONS_SUBDIR: &str = "sessions";
diff --git a/codex-rs/rollout/src/recorder.rs b/codex-rs/rollout/src/recorder.rs
index 53bf115d8..dad7f8bc3 100644
--- a/codex-rs/rollout/src/recorder.rs
+++ b/codex-rs/rollout/src/recorder.rs
@@ -46,7 +46,6 @@ use super::list::parse_timestamp_uuid_from_filename;
 use super::metadata;
 use super::session_index::find_thread_names_by_ids;
 use crate::config::RolloutConfigView;
-use crate::default_client::originator;
 use crate::state_db;
 use crate::state_db::StateDbHandle;
 use codex_git_utils::collect_git_info;
@@ -89,6 +88,7 @@ pub enum RolloutRecorderParams {
         parent_thread_id: Option<ThreadId>,
         source: Box<SessionSource>,
         thread_source: Option<ThreadSource>,
+        originator: String,
         base_instructions: BaseInstructions,
         dynamic_tools: Vec<DynamicToolSpec>,
         multi_agent_version: Option<MultiAgentVersion>,
@@ -161,12 +161,14 @@ fn clone_io_error(err: &IoError) -> IoError {
 }
 
 impl RolloutRecorderParams {
+    #[allow(clippy::too_many_arguments)]
     pub fn new(
         conversation_id: ThreadId,
         forked_from_id: Option<ThreadId>,
         parent_thread_id: Option<ThreadId>,
         source: SessionSource,
         thread_source: Option<ThreadSource>,
+        originator: String,
         base_instructions: BaseInstructions,
         dynamic_tools: Vec<DynamicToolSpec>,
     ) -> Self {
@@ -177,6 +179,7 @@ impl RolloutRecorderParams {
             parent_thread_id,
             source: Box::new(source),
             thread_source,
+            originator,
             base_instructions,
             dynamic_tools,
             multi_agent_version: None,
@@ -726,6 +729,7 @@ impl RolloutRecorder {
                 parent_thread_id,
                 source,
                 thread_source,
+                originator,
                 base_instructions,
                 dynamic_tools,
                 multi_agent_version,
@@ -751,7 +755,7 @@ impl RolloutRecorder {
                     parent_thread_id,
                     timestamp,
                     cwd: config.cwd().to_path_buf(),
-                    originator: originator().value,
+                    originator,
                     cli_version: env!("CARGO_PKG_VERSION").to_string(),
                     agent_nickname: source.get_nickname(),
                     agent_role: source.get_agent_role(),
diff --git a/codex-rs/rollout/src/recorder_tests.rs b/codex-rs/rollout/src/recorder_tests.rs
index 23618cb81..4b72ff767 100644
--- a/codex-rs/rollout/src/recorder_tests.rs
+++ b/codex-rs/rollout/src/recorder_tests.rs
@@ -385,6 +385,7 @@ async fn recorder_materializes_on_flush_with_pending_items() -> std::io::Result<
             /*parent_thread_id*/ None,
             SessionSource::Exec,
             /*thread_source*/ None,
+            "test_originator".to_string(),
             BaseInstructions::default(),
             Vec::new(),
         )
@@ -477,6 +478,7 @@ async fn persist_reports_filesystem_error_and_retries_buffered_items() -> std::i
             /*parent_thread_id*/ None,
             SessionSource::Exec,
             /*thread_source*/ None,
+            "test_originator".to_string(),
             BaseInstructions::default(),
             Vec::new(),
         ),
diff --git a/codex-rs/thread-store/src/in_memory.rs b/codex-rs/thread-store/src/in_memory.rs
index d7d85c3cf..8cd801c9c 100644
--- a/codex-rs/thread-store/src/in_memory.rs
+++ b/codex-rs/thread-store/src/in_memory.rs
@@ -118,6 +118,7 @@ mod tests {
                     parent_thread_id,
                     source: SessionSource::Exec,
                     thread_source: None,
+                    originator: "test_originator".to_string(),
                     base_instructions: BaseInstructions::default(),
                     dynamic_tools: Vec::new(),
                     multi_agent_version: None,
@@ -242,6 +243,7 @@ impl InMemoryThreadStore {
             agent_nickname: params.source.get_nickname(),
             agent_role: params.source.get_agent_role(),
             agent_path: params.source.get_agent_path().map(Into::into),
+            originator: params.originator.clone(),
             source: params.source.clone(),
             thread_source: params.thread_source.clone(),
             model_provider: Some(params.metadata.model_provider.clone()),
diff --git a/codex-rs/thread-store/src/local/create_thread.rs b/codex-rs/thread-store/src/local/create_thread.rs
index 36c3cdc13..eba6a5a6a 100644
--- a/codex-rs/thread-store/src/local/create_thread.rs
+++ b/codex-rs/thread-store/src/local/create_thread.rs
@@ -33,6 +33,7 @@ pub(super) async fn create_thread(
             params.parent_thread_id,
             params.source,
             params.thread_source,
+            params.originator,
             params.base_instructions,
             params.dynamic_tools,
         )
diff --git a/codex-rs/thread-store/src/local/mod.rs b/codex-rs/thread-store/src/local/mod.rs
index d0a4d6518..51e622fc5 100644
--- a/codex-rs/thread-store/src/local/mod.rs
+++ b/codex-rs/thread-store/src/local/mod.rs
@@ -1130,6 +1130,7 @@ mod tests {
             parent_thread_id: None,
             source: SessionSource::Exec,
             thread_source: None,
+            originator: "test_originator".to_string(),
             base_instructions: BaseInstructions::default(),
             dynamic_tools: Vec::new(),
             multi_agent_version: None,
diff --git a/codex-rs/thread-store/src/types.rs b/codex-rs/thread-store/src/types.rs
index c18f39882..feea814f9 100644
--- a/codex-rs/thread-store/src/types.rs
+++ b/codex-rs/thread-store/src/types.rs
@@ -79,6 +79,8 @@ pub struct CreateThreadParams {
     pub source: SessionSource,
     /// Optional analytics source classification for this thread.
     pub thread_source: Option<ThreadSource>,
+    /// Effective originator used for this thread's Responses requests and analytics events.
+    pub originator: String,
     /// Base instructions persisted in session metadata.
     pub base_instructions: BaseInstructions,
     /// Dynamic tools available to the thread at startup.