diff --git a/codex-rs/analytics/src/accepted_line_events.rs b/codex-rs/analytics/src/accepted_line_events.rs
new file mode 100644
index 0000000000..9e9bcb2419
--- /dev/null
+++ b/codex-rs/analytics/src/accepted_line_events.rs
@@ -0,0 +1,112 @@
+use crate::accepted_lines::fingerprint_hash;
+use crate::events::CodexAcceptedLineFingerprintsEventParams;
+use crate::events::CodexAcceptedLineFingerprintsEventRequest;
+use crate::events::TrackEventRequest;
+use crate::facts::AcceptedLineFingerprint;
+use codex_git_utils::canonicalize_git_remote_url;
+use codex_git_utils::get_git_remote_urls_assume_git_repo;
+use std::path::Path;
+
+const ACCEPTED_LINE_FINGERPRINT_EVENT_TARGET_BYTES: usize = 2 * 1024 * 1024;
+const ACCEPTED_LINE_FINGERPRINT_EVENT_FIXED_BYTES: usize = 1024;
+
+pub(crate) struct AcceptedLineFingerprintEventInput {
+    pub(crate) event_type: &'static str,
+    pub(crate) turn_id: String,
+    pub(crate) thread_id: String,
+    pub(crate) product_surface: Option<String>,
+    pub(crate) model_slug: Option<String>,
+    pub(crate) completed_at: u64,
+    pub(crate) repo_hash: Option<String>,
+    pub(crate) accepted_added_lines: u64,
+    pub(crate) accepted_deleted_lines: u64,
+    pub(crate) line_fingerprints: Vec<AcceptedLineFingerprint>,
+}
+
+pub(crate) fn accepted_line_fingerprint_event_requests(
+    input: AcceptedLineFingerprintEventInput,
+) -> Vec<TrackEventRequest> {
+    let chunks = accepted_line_fingerprint_chunks(input.line_fingerprints);
+    chunks
+        .into_iter()
+        .enumerate()
+        .map(|(index, line_fingerprints)| {
+            let is_first_chunk = index == 0;
+            TrackEventRequest::AcceptedLineFingerprints(Box::new(
+                CodexAcceptedLineFingerprintsEventRequest {
+                    event_type: "codex_accepted_line_fingerprints",
+                    event_params: CodexAcceptedLineFingerprintsEventParams {
+                        event_type: input.event_type,
+                        turn_id: input.turn_id.clone(),
+                        thread_id: input.thread_id.clone(),
+                        product_surface: input.product_surface.clone(),
+                        model_slug: input.model_slug.clone(),
+                        completed_at: input.completed_at,
+                        repo_hash: input.repo_hash.clone(),
+                        accepted_added_lines: if is_first_chunk {
+                            input.accepted_added_lines
+                        } else {
+                            0
+                        },
+                        accepted_deleted_lines: if is_first_chunk {
+                            input.accepted_deleted_lines
+                        } else {
+                            0
+                        },
+                        line_fingerprints,
+                    },
+                },
+            ))
+        })
+        .collect()
+}
+
+pub async fn accepted_line_repo_hash_for_cwd(cwd: &Path) -> Option<String> {
+    let remotes = get_git_remote_urls_assume_git_repo(cwd).await?;
+    remotes
+        .get("origin")
+        .or_else(|| remotes.values().next())
+        .map(|remote_url| {
+            let canonical_remote_url =
+                canonicalize_git_remote_url(remote_url).unwrap_or_else(|| remote_url.to_string());
+            fingerprint_hash("repo", &canonical_remote_url)
+        })
+}
+
+fn accepted_line_fingerprint_chunks(
+    line_fingerprints: Vec<AcceptedLineFingerprint>,
+) -> Vec<Vec<AcceptedLineFingerprint>> {
+    if line_fingerprints.is_empty() {
+        return vec![Vec::new()];
+    }
+
+    let mut chunks = Vec::new();
+    let mut current = Vec::new();
+    let mut current_bytes = ACCEPTED_LINE_FINGERPRINT_EVENT_FIXED_BYTES;
+
+    for fingerprint in line_fingerprints {
+        let item_bytes = accepted_line_fingerprint_json_bytes(&fingerprint);
+        let separator_bytes = usize::from(!current.is_empty());
+        if !current.is_empty()
+            && current_bytes + separator_bytes + item_bytes
+                > ACCEPTED_LINE_FINGERPRINT_EVENT_TARGET_BYTES
+        {
+            chunks.push(current);
+            current = Vec::new();
+            current_bytes = ACCEPTED_LINE_FINGERPRINT_EVENT_FIXED_BYTES;
+        }
+        current_bytes += usize::from(!current.is_empty()) + item_bytes;
+        current.push(fingerprint);
+    }
+
+    if !current.is_empty() {
+        chunks.push(current);
+    }
+    chunks
+}
+
+fn accepted_line_fingerprint_json_bytes(fingerprint: &AcceptedLineFingerprint) -> usize {
+    // {"path_hash":"...","line_hash":"..."} plus one byte of array comma
+    // accounted for by the caller when needed.
+    32 + fingerprint.path_hash.len() + fingerprint.line_hash.len()
+}
diff --git a/codex-rs/analytics/src/accepted_lines.rs b/codex-rs/analytics/src/accepted_lines.rs
new file mode 100644
index 0000000000..c7fdb6f3c7
--- /dev/null
+++ b/codex-rs/analytics/src/accepted_lines.rs
@@ -0,0 +1,188 @@
+use crate::facts::AcceptedLineFingerprint;
+use sha1::Digest;
+
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub struct AcceptedLineFingerprintSummary {
+    pub accepted_added_lines: u64,
+    pub accepted_deleted_lines: u64,
+    pub line_fingerprints: Vec<AcceptedLineFingerprint>,
+}
+
+pub fn accepted_line_fingerprints_from_unified_diff(
+    unified_diff: &str,
+) -> AcceptedLineFingerprintSummary {
+    let mut current_path: Option<String> = None;
+    let mut in_hunk = false;
+    let mut accepted_added_lines = 0;
+    let mut accepted_deleted_lines = 0;
+    let mut line_fingerprints = Vec::new();
+
+    for line in unified_diff.lines() {
+        if line.starts_with("diff --git ") {
+            current_path = None;
+            in_hunk = false;
+            continue;
+        }
+
+        if line.starts_with("@@ ") {
+            in_hunk = true;
+            continue;
+        }
+
+        if !in_hunk && let Some(path) = line.strip_prefix("+++ ") {
+            current_path = normalize_diff_path(path);
+            continue;
+        }
+
+        if !in_hunk && line.starts_with("--- ") {
+            continue;
+        }
+
+        if let Some(added_line) = line.strip_prefix('+') {
+            accepted_added_lines += 1;
+            if let Some(path) = current_path.as_deref()
+                && let Some(normalized_line) = normalize_effective_line(added_line)
+            {
+                line_fingerprints.push(AcceptedLineFingerprint {
+                    path_hash: fingerprint_hash("path", path),
+                    line_hash: fingerprint_hash("line", &normalized_line),
+                });
+            }
+            continue;
+        }
+
+        if line.starts_with('-') {
+            accepted_deleted_lines += 1;
+        }
+    }
+
+    AcceptedLineFingerprintSummary {
+        accepted_added_lines,
+        accepted_deleted_lines,
+        line_fingerprints,
+    }
+}
+
+pub fn fingerprint_hash(domain: &str, value: &str) -> String {
+    let mut hasher = sha1::Sha1::new();
+    hasher.update(b"file-line-v1\0");
+    hasher.update(domain.as_bytes());
+    hasher.update(b"\0");
+    hasher.update(value.as_bytes());
+    format!("{:x}", hasher.finalize())
+}
+
+fn normalize_diff_path(path: &str) -> Option<String> {
+    let path = path.trim();
+    if path == "/dev/null" {
+        return None;
+    }
+
+    Some(
+        path.strip_prefix("b/")
+            .or_else(|| path.strip_prefix("a/"))
+            .unwrap_or(path)
+            .to_string(),
+    )
+}
+
+fn normalize_effective_line(line: &str) -> Option<String> {
+    let normalized = line.split_whitespace().collect::<Vec<_>>().join(" ");
+    if normalized.len() <= 3 {
+        return None;
+    }
+    if !normalized
+        .chars()
+        .any(|ch| ch.is_alphanumeric() || ch == '_')
+    {
+        return None;
+    }
+    Some(normalized)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn parses_counts_and_effective_added_fingerprints() {
+        let diff = "\
+diff --git a/src/lib.rs b/src/lib.rs
+index 1111111..2222222
+--- a/src/lib.rs
++++ b/src/lib.rs
+@@ -1,3 +1,5 @@
+-old line
++fn useful() {
++}
++    return user.id;
+ context
+";
+
+        let summary = accepted_line_fingerprints_from_unified_diff(diff);
+
+        assert_eq!(
+            summary,
+            AcceptedLineFingerprintSummary {
+                accepted_added_lines: 3,
+                accepted_deleted_lines: 1,
+                line_fingerprints: vec![
+                    AcceptedLineFingerprint {
+                        path_hash: fingerprint_hash("path", "src/lib.rs"),
+                        line_hash: fingerprint_hash("line", "fn useful() {"),
+                    },
+                    AcceptedLineFingerprint {
+                        path_hash: fingerprint_hash("path", "src/lib.rs"),
+                        line_hash: fingerprint_hash("line", "return user.id;"),
+                    },
+                ],
+            }
+        );
+    }
+
+    #[test]
+    fn skips_added_file_metadata_headers() {
+        let diff = "\
+diff --git a/new.py b/new.py
+new file mode 100644
+index 0000000..1111111
+--- /dev/null
++++ b/new.py
+@@ -0,0 +1 @@
++print('hello')
+";
+
+        let summary = accepted_line_fingerprints_from_unified_diff(diff);
+
+        assert_eq!(summary.accepted_added_lines, 1);
+        assert_eq!(summary.accepted_deleted_lines, 0);
+        assert_eq!(summary.line_fingerprints.len(), 1);
+    }
+
+    #[test]
+    fn parses_hunk_lines_that_look_like_file_headers() {
+        let diff = "\
+diff --git a/src/lib.rs b/src/lib.rs
+index 1111111..2222222
+--- a/src/lib.rs
++++ b/src/lib.rs
+@@ -1,2 +1,2 @@
+--- old value
++++ new value
+";
+
+        let summary = accepted_line_fingerprints_from_unified_diff(diff);
+
+        assert_eq!(
+            summary,
+            AcceptedLineFingerprintSummary {
+                accepted_added_lines: 1,
+                accepted_deleted_lines: 1,
+                line_fingerprints: vec![AcceptedLineFingerprint {
+                    path_hash: fingerprint_hash("path", "src/lib.rs"),
+                    line_hash: fingerprint_hash("line", "++ new value"),
+                }],
+            }
+        );
+    }
+}
diff --git a/codex-rs/analytics/src/analytics_client_tests.rs b/codex-rs/analytics/src/analytics_client_tests.rs
index 880adfc254..462b89c64a 100644
--- a/codex-rs/analytics/src/analytics_client_tests.rs
+++ b/codex-rs/analytics/src/analytics_client_tests.rs
@@ -1,5 +1,7 @@
 use crate::client::AnalyticsEventsQueue;
 use crate::events::AppServerRpcTransport;
+use crate::events::CodexAcceptedLineFingerprintsEventParams;
+use crate::events::CodexAcceptedLineFingerprintsEventRequest;
 use crate::events::CodexAppMentionedEventRequest;
 use crate::events::CodexAppServerClientMetadata;
 use crate::events::CodexAppUsedEventRequest;
@@ -28,6 +30,7 @@ use crate::events::codex_hook_run_metadata;
 use crate::events::codex_plugin_metadata;
 use crate::events::codex_plugin_used_metadata;
 use crate::events::subagent_thread_started_event_request;
+use crate::facts::AcceptedLineFingerprint;
 use crate::facts::AnalyticsFact;
 use crate::facts::AnalyticsJsonRpcError;
 use crate::facts::AppInvocation;
@@ -89,6 +92,7 @@ use codex_app_server_protocol::ThreadStartResponse;
 use codex_app_server_protocol::ThreadStatus as AppServerThreadStatus;
 use codex_app_server_protocol::Turn;
 use codex_app_server_protocol::TurnCompletedNotification;
+use codex_app_server_protocol::TurnDiffUpdatedNotification;
 use codex_app_server_protocol::TurnError as AppServerTurnError;
 use codex_app_server_protocol::TurnStartParams;
 use codex_app_server_protocol::TurnStartedNotification;
@@ -827,6 +831,206 @@ fn app_used_event_serializes_expected_shape() {
     );
 }
 
+#[test]
+fn accepted_line_fingerprints_event_serializes_expected_shape() {
+    let event = TrackEventRequest::AcceptedLineFingerprints(Box::new(
+        CodexAcceptedLineFingerprintsEventRequest {
+            event_type: "codex_accepted_line_fingerprints",
+            event_params: CodexAcceptedLineFingerprintsEventParams {
+                event_type: "codex.accepted_line_fingerprints",
+                turn_id: "turn-1".to_string(),
+                thread_id: "thread-1".to_string(),
+                product_surface: Some("codex".to_string()),
+                model_slug: Some("gpt-5.1-codex".to_string()),
+                completed_at: 1710000000,
+                repo_hash: Some("repo-hash-1".to_string()),
+                accepted_added_lines: 42,
+                accepted_deleted_lines: 40,
+                line_fingerprints: vec![AcceptedLineFingerprint {
+                    path_hash: "path-hash-1".to_string(),
+                    line_hash: "line-hash-1".to_string(),
+                }],
+            },
+        },
+    ));
+
+    let payload = serde_json::to_value(&event).expect("serialize accepted line fingerprints event");
+
+    assert_eq!(
+        payload,
+        json!({
+            "event_type": "codex_accepted_line_fingerprints",
+            "event_params": {
+                "event_type": "codex.accepted_line_fingerprints",
+                "turn_id": "turn-1",
+                "thread_id": "thread-1",
+                "product_surface": "codex",
+                "model_slug": "gpt-5.1-codex",
+                "completed_at": 1710000000,
+                "repo_hash": "repo-hash-1",
+                "accepted_added_lines": 42,
+                "accepted_deleted_lines": 40,
+                "line_fingerprints": [
+                    {
+                        "path_hash": "path-hash-1",
+                        "line_hash": "line-hash-1"
+                    }
+                ]
+            }
+        })
+    );
+}
+
+#[tokio::test]
+async fn reducer_chunks_large_accepted_line_fingerprint_events_without_repeating_counts() {
+    let mut reducer = AnalyticsReducer::default();
+    let mut events = Vec::new();
+
+    ingest_turn_prerequisites(
+        &mut reducer,
+        &mut events,
+        /*include_initialize*/ true,
+        /*include_resolved_config*/ true,
+        /*include_started*/ true,
+        /*include_token_usage*/ true,
+    )
+    .await;
+    events.clear();
+
+    let mut diff = "\
+diff --git a/src/lib.rs b/src/lib.rs
+index 1111111..2222222
+--- a/src/lib.rs
++++ b/src/lib.rs
+@@ -0,0 +1,20000 @@
+"
+    .to_string();
+    for index in 0..20_000 {
+        diff.push_str(&format!("+let value_{index} = {index};\n"));
+    }
+
+    reducer
+        .ingest(
+            AnalyticsFact::Notification(Box::new(ServerNotification::TurnDiffUpdated(
+                TurnDiffUpdatedNotification {
+                    thread_id: "thread-2".to_string(),
+                    turn_id: "turn-2".to_string(),
+                    diff,
+                },
+            ))),
+            &mut events,
+        )
+        .await;
+    assert!(events.is_empty());
+
+    reducer
+        .ingest(
+            AnalyticsFact::Notification(Box::new(sample_turn_completed_notification(
+                "thread-2",
+                "turn-2",
+                AppServerTurnStatus::Completed,
+                /*codex_error_info*/ None,
+            ))),
+            &mut events,
+        )
+        .await;
+
+    let accepted_line_events = events
+        .iter()
+        .filter_map(|event| match event {
+            TrackEventRequest::AcceptedLineFingerprints(event) => Some(event),
+            _ => None,
+        })
+        .collect::<Vec<_>>();
+    assert!(accepted_line_events.len() > 1);
+    let mut total_fingerprints = 0;
+    for (index, event) in accepted_line_events.iter().enumerate() {
+        assert_eq!(event.event_params.turn_id, "turn-2");
+        assert_eq!(event.event_params.thread_id, "thread-2");
+        total_fingerprints += event.event_params.line_fingerprints.len();
+        if index == 0 {
+            assert_eq!(event.event_params.accepted_added_lines, 20_000);
+            assert_eq!(event.event_params.accepted_deleted_lines, 0);
+        } else {
+            assert_eq!(event.event_params.accepted_added_lines, 0);
+            assert_eq!(event.event_params.accepted_deleted_lines, 0);
+        }
+        assert!(serde_json::to_vec(event).expect("serialize chunk").len() < 2_100_000);
+    }
+    assert_eq!(total_fingerprints, 20_000);
+}
+
+#[tokio::test]
+async fn reducer_emits_accepted_line_fingerprints_once_from_latest_turn_diff_on_completion() {
+    let mut reducer = AnalyticsReducer::default();
+    let mut events = Vec::new();
+
+    ingest_turn_prerequisites(
+        &mut reducer,
+        &mut events,
+        /*include_initialize*/ true,
+        /*include_resolved_config*/ true,
+        /*include_started*/ true,
+        /*include_token_usage*/ true,
+    )
+    .await;
+    events.clear();
+
+    for line in ["let old_value = 1;", "let latest_value = 2;"] {
+        let diff = format!(
+            "\
+diff --git a/src/lib.rs b/src/lib.rs
+index 1111111..2222222
+--- a/src/lib.rs
++++ b/src/lib.rs
+@@ -0,0 +1 @@
++{line}
+"
+        );
+        reducer
+            .ingest(
+                AnalyticsFact::Notification(Box::new(ServerNotification::TurnDiffUpdated(
+                    TurnDiffUpdatedNotification {
+                        thread_id: "thread-2".to_string(),
+                        turn_id: "turn-2".to_string(),
+                        diff,
+                    },
+                ))),
+                &mut events,
+            )
+            .await;
+    }
+    assert!(events.is_empty());
+
+    reducer
+        .ingest(
+            AnalyticsFact::Notification(Box::new(sample_turn_completed_notification(
+                "thread-2",
+                "turn-2",
+                AppServerTurnStatus::Completed,
+                /*codex_error_info*/ None,
+            ))),
+            &mut events,
+        )
+        .await;
+
+    let accepted_line_events = events
+        .iter()
+        .filter_map(|event| match event {
+            TrackEventRequest::AcceptedLineFingerprints(event) => Some(event),
+            _ => None,
+        })
+        .collect::<Vec<_>>();
+    assert_eq!(accepted_line_events.len(), 1);
+    let event = accepted_line_events[0];
+    assert_eq!(event.event_params.accepted_added_lines, 1);
+    assert_eq!(event.event_params.line_fingerprints.len(), 1);
+    assert_eq!(
+        event.event_params.line_fingerprints[0].line_hash,
+        crate::fingerprint_hash("line", "let latest_value = 2;")
+    );
+}
+
 #[test]
 fn compaction_event_serializes_expected_shape() {
     let event = TrackEventRequest::Compaction(Box::new(CodexCompactionEventRequest {
diff --git a/codex-rs/analytics/src/client.rs b/codex-rs/analytics/src/client.rs
index 6d6d446560..1f2a7015c6 100644
--- a/codex-rs/analytics/src/client.rs
+++ b/codex-rs/analytics/src/client.rs
@@ -30,6 +30,7 @@ use codex_app_server_protocol::ServerNotification;
 use codex_app_server_protocol::ServerRequest;
 use codex_app_server_protocol::ServerResponse;
 use codex_login::AuthManager;
+use codex_login::CodexAuth;
 use codex_login::default_client::create_client;
 use codex_plugin::PluginTelemetryMetadata;
 use std::collections::HashSet;
@@ -351,6 +352,7 @@ impl AnalyticsEventsClient {
             notification,
             ServerNotification::TurnStarted(_)
                 | ServerNotification::TurnCompleted(_)
+                | ServerNotification::TurnDiffUpdated(_)
                 | ServerNotification::ItemStarted(_)
                 | ServerNotification::ItemCompleted(_)
                 | ServerNotification::ItemGuardianApprovalReviewStarted(_)
@@ -370,6 +372,7 @@ async fn send_track_events(
     if events.is_empty() {
         return;
     }
+
     let Some(auth) = auth_manager.auth().await else {
         return;
     };
@@ -379,12 +382,45 @@ async fn send_track_events(
 
     let base_url = base_url.trim_end_matches('/');
     let url = format!("{base_url}/codex/analytics-events/events");
+    for events in track_event_request_batches(events) {
+        send_track_events_request(&auth, &url, events).await;
+    }
+}
+
+fn track_event_request_batches(events: Vec<TrackEventRequest>) -> Vec<Vec<TrackEventRequest>> {
+    let mut batches = Vec::new();
+    let mut current_batch = Vec::new();
+
+    for event in events {
+        if event.should_send_in_isolated_request() {
+            if !current_batch.is_empty() {
+                batches.push(current_batch);
+                current_batch = Vec::new();
+            }
+            batches.push(vec![event]);
+        } else {
+            current_batch.push(event);
+        }
+    }
+
+    if !current_batch.is_empty() {
+        batches.push(current_batch);
+    }
+
+    batches
+}
+
+async fn send_track_events_request(auth: &CodexAuth, url: &str, events: Vec<TrackEventRequest>) {
+    if events.is_empty() {
+        return;
+    }
+
     let payload = TrackEventsRequest { events };
 
     let response = create_client()
-        .post(&url)
+        .post(url)
         .timeout(ANALYTICS_EVENTS_TIMEOUT)
-        .headers(codex_model_provider::auth_provider_from_auth(&auth).to_auth_headers())
+        .headers(codex_model_provider::auth_provider_from_auth(auth).to_auth_headers())
         .header("Content-Type", "application/json")
         .json(&payload)
         .send()
diff --git a/codex-rs/analytics/src/client_tests.rs b/codex-rs/analytics/src/client_tests.rs
index 3021d558d6..2ddc21e477 100644
--- a/codex-rs/analytics/src/client_tests.rs
+++ b/codex-rs/analytics/src/client_tests.rs
@@ -1,6 +1,14 @@
 use super::AnalyticsEventsClient;
 use super::AnalyticsEventsQueue;
+use super::track_event_request_batches;
+use crate::events::CodexAcceptedLineFingerprintsEventParams;
+use crate::events::CodexAcceptedLineFingerprintsEventRequest;
+use crate::events::SkillInvocationEventParams;
+use crate::events::SkillInvocationEventRequest;
+use crate::events::TrackEventRequest;
+use crate::facts::AcceptedLineFingerprint;
 use crate::facts::AnalyticsFact;
+use crate::facts::InvocationType;
 use codex_app_server_protocol::ApprovalsReviewer as AppServerApprovalsReviewer;
 use codex_app_server_protocol::AskForApproval as AppServerAskForApproval;
 use codex_app_server_protocol::ClientRequest;
@@ -31,6 +39,47 @@ use std::sync::Mutex;
 use tokio::sync::mpsc;
 use tokio::sync::mpsc::error::TryRecvError;
 
+fn sample_accepted_line_fingerprint_event(thread_id: &str) -> TrackEventRequest {
+    TrackEventRequest::AcceptedLineFingerprints(Box::new(
+        CodexAcceptedLineFingerprintsEventRequest {
+            event_type: "codex_accepted_line_fingerprints",
+            event_params: CodexAcceptedLineFingerprintsEventParams {
+                event_type: "codex.accepted_line_fingerprints",
+                turn_id: "turn-1".to_string(),
+                thread_id: thread_id.to_string(),
+                product_surface: Some("codex".to_string()),
+                model_slug: Some("gpt-5.1-codex".to_string()),
+                completed_at: 1,
+                repo_hash: None,
+                accepted_added_lines: 1,
+                accepted_deleted_lines: 0,
+                line_fingerprints: vec![AcceptedLineFingerprint {
+                    path_hash: "path-hash".to_string(),
+                    line_hash: "line-hash".to_string(),
+                }],
+            },
+        },
+    ))
+}
+
+fn sample_regular_track_event(thread_id: &str) -> TrackEventRequest {
+    TrackEventRequest::SkillInvocation(SkillInvocationEventRequest {
+        event_type: "skill_invocation",
+        skill_id: format!("skill-{thread_id}"),
+        skill_name: "doc".to_string(),
+        event_params: SkillInvocationEventParams {
+            product_client_id: None,
+            skill_scope: None,
+            plugin_id: None,
+            repo_url: None,
+            thread_id: Some(thread_id.to_string()),
+            turn_id: Some("turn-1".to_string()),
+            invoke_type: Some(InvocationType::Explicit),
+            model_slug: Some("gpt-5.1-codex".to_string()),
+        },
+    })
+}
+
 fn client_with_receiver() -> (AnalyticsEventsClient, mpsc::Receiver<AnalyticsFact>) {
     let (sender, receiver) = mpsc::channel(8);
     let queue = AnalyticsEventsQueue {
@@ -222,3 +271,23 @@ fn track_response_only_enqueues_analytics_relevant_responses() {
     );
     assert!(matches!(receiver.try_recv(), Err(TryRecvError::Empty)));
 }
+
+#[test]
+fn track_event_request_batches_only_isolates_accepted_line_fingerprint_events() {
+    let batches = track_event_request_batches(vec![
+        sample_regular_track_event("thread-1"),
+        sample_regular_track_event("thread-2"),
+        sample_accepted_line_fingerprint_event("thread-3"),
+        sample_accepted_line_fingerprint_event("thread-4"),
+        sample_regular_track_event("thread-5"),
+        sample_regular_track_event("thread-6"),
+    ]);
+
+    assert_eq!(batches.len(), 4);
+    assert_eq!(batches[0].len(), 2);
+    assert_eq!(batches[1].len(), 1);
+    assert_eq!(batches[2].len(), 1);
+    assert_eq!(batches[3].len(), 2);
+    assert!(batches[1][0].should_send_in_isolated_request());
+    assert!(batches[2][0].should_send_in_isolated_request());
+}
diff --git a/codex-rs/analytics/src/events.rs b/codex-rs/analytics/src/events.rs
index 23afd83b75..f058988d6c 100644
--- a/codex-rs/analytics/src/events.rs
+++ b/codex-rs/analytics/src/events.rs
@@ -1,5 +1,6 @@
 use std::time::Instant;
 
+use crate::facts::AcceptedLineFingerprint;
 use crate::facts::AppInvocation;
 use crate::facts::CodexCompactionEvent;
 use crate::facts::CompactionImplementation;
@@ -70,6 +71,7 @@ pub(crate) enum TrackEventRequest {
     CollabAgentToolCall(CodexCollabAgentToolCallEventRequest),
     WebSearch(CodexWebSearchEventRequest),
     ImageGeneration(CodexImageGenerationEventRequest),
+    AcceptedLineFingerprints(Box<CodexAcceptedLineFingerprintsEventRequest>),
     #[allow(dead_code)]
     ReviewEvent(CodexReviewEventRequest),
     PluginUsed(CodexPluginUsedEventRequest),
@@ -79,6 +81,32 @@ pub(crate) enum TrackEventRequest {
     PluginDisabled(CodexPluginEventRequest),
 }
 
+impl TrackEventRequest {
+    pub(crate) fn should_send_in_isolated_request(&self) -> bool {
+        matches!(self, Self::AcceptedLineFingerprints(_))
+    }
+}
+
+#[derive(Serialize)]
+pub(crate) struct CodexAcceptedLineFingerprintsEventParams {
+    pub(crate) event_type: &'static str,
+    pub(crate) turn_id: String,
+    pub(crate) thread_id: String,
+    pub(crate) product_surface: Option<String>,
+    pub(crate) model_slug: Option<String>,
+    pub(crate) completed_at: u64,
+    pub(crate) repo_hash: Option<String>,
+    pub(crate) accepted_added_lines: u64,
+    pub(crate) accepted_deleted_lines: u64,
+    pub(crate) line_fingerprints: Vec<AcceptedLineFingerprint>,
+}
+
+#[derive(Serialize)]
+pub(crate) struct CodexAcceptedLineFingerprintsEventRequest {
+    pub(crate) event_type: &'static str,
+    pub(crate) event_params: CodexAcceptedLineFingerprintsEventParams,
+}
+
 #[derive(Serialize)]
 pub(crate) struct SkillInvocationEventRequest {
     pub(crate) event_type: &'static str,
diff --git a/codex-rs/analytics/src/facts.rs b/codex-rs/analytics/src/facts.rs
index 861e6534a2..db35f7469d 100644
--- a/codex-rs/analytics/src/facts.rs
+++ b/codex-rs/analytics/src/facts.rs
@@ -28,6 +28,12 @@ use codex_protocol::protocol::TokenUsage;
 use serde::Serialize;
 use std::path::PathBuf;
 
+#[derive(Clone, Debug, PartialEq, Eq, Serialize)]
+pub struct AcceptedLineFingerprint {
+    pub path_hash: String,
+    pub line_hash: String,
+}
+
 #[derive(Clone)]
 pub struct TrackEventsContext {
     pub model_slug: String,
diff --git a/codex-rs/analytics/src/lib.rs b/codex-rs/analytics/src/lib.rs
index 2fb23199cb..55e9c1b1f8 100644
--- a/codex-rs/analytics/src/lib.rs
+++ b/codex-rs/analytics/src/lib.rs
@@ -1,3 +1,5 @@
+mod accepted_line_events;
+mod accepted_lines;
 mod client;
 mod events;
 mod facts;
@@ -6,6 +8,8 @@ mod reducer;
 use std::time::SystemTime;
 use std::time::UNIX_EPOCH;
 
+pub use accepted_lines::accepted_line_fingerprints_from_unified_diff;
+pub use accepted_lines::fingerprint_hash;
 pub use client::AnalyticsEventsClient;
 pub use events::AppServerRpcTransport;
 pub use events::GuardianApprovalRequestSource;
@@ -17,6 +21,7 @@ pub use events::GuardianReviewSessionKind;
 pub use events::GuardianReviewTerminalStatus;
 pub use events::GuardianReviewTrackContext;
 pub use events::GuardianReviewedAction;
+pub use facts::AcceptedLineFingerprint;
 pub use facts::AnalyticsJsonRpcError;
 pub use facts::AppInvocation;
 pub use facts::CodexCompactionEvent;
diff --git a/codex-rs/analytics/src/reducer.rs b/codex-rs/analytics/src/reducer.rs
index d35fb96602..067e8252f6 100644
--- a/codex-rs/analytics/src/reducer.rs
+++ b/codex-rs/analytics/src/reducer.rs
@@ -1,3 +1,7 @@
+use crate::accepted_line_events::AcceptedLineFingerprintEventInput;
+use crate::accepted_line_events::accepted_line_fingerprint_event_requests;
+use crate::accepted_line_events::accepted_line_repo_hash_for_cwd;
+use crate::accepted_lines::accepted_line_fingerprints_from_unified_diff;
 use crate::events::AppServerRpcTransport;
 use crate::events::CodexAppMentionedEventRequest;
 use crate::events::CodexAppServerClientMetadata;
@@ -104,6 +108,7 @@ use codex_protocol::protocol::TokenUsage;
 use sha1::Digest;
 use std::collections::HashMap;
 use std::path::Path;
+use std::path::PathBuf;
 
 #[derive(Default)]
 pub(crate) struct AnalyticsReducer {
@@ -264,6 +269,7 @@ struct TurnState {
     started_at: Option<u64>,
     token_usage: Option<TokenUsage>,
     completed: Option<CompletedTurnState>,
+    latest_diff: Option<String>,
     steer_count: usize,
 }
 
@@ -305,7 +311,7 @@ impl AnalyticsReducer {
                 response,
             } => {
                 if let Some(response) = response.into_client_response(request_id) {
-                    self.ingest_response(connection_id, response, out);
+                    self.ingest_response(connection_id, response, out).await;
                 }
             }
             AnalyticsFact::ErrorResponse {
@@ -317,7 +323,7 @@ impl AnalyticsReducer {
                 self.ingest_error_response(connection_id, request_id, error_type, out);
             }
             AnalyticsFact::Notification(notification) => {
-                self.ingest_notification(*notification, out);
+                self.ingest_notification(*notification, out).await;
             }
             AnalyticsFact::ServerRequest {
                 connection_id: _connection_id,
@@ -337,10 +343,10 @@ impl AnalyticsReducer {
                     self.ingest_guardian_review(*input, out);
                 }
                 CustomAnalyticsFact::TurnResolvedConfig(input) => {
-                    self.ingest_turn_resolved_config(*input, out);
+                    self.ingest_turn_resolved_config(*input, out).await;
                 }
                 CustomAnalyticsFact::TurnTokenUsage(input) => {
-                    self.ingest_turn_token_usage(*input, out);
+                    self.ingest_turn_token_usage(*input, out).await;
                 }
                 CustomAnalyticsFact::SkillInvoked(input) => {
                     self.ingest_skill_invoked(input, out).await;
@@ -472,7 +478,7 @@ impl AnalyticsReducer {
         }
     }
 
-    fn ingest_turn_resolved_config(
+    async fn ingest_turn_resolved_config(
         &mut self,
         input: TurnResolvedConfigFact,
         out: &mut Vec<TrackEventRequest>,
@@ -488,15 +494,16 @@ impl AnalyticsReducer {
             started_at: None,
             token_usage: None,
             completed: None,
+            latest_diff: None,
             steer_count: 0,
         });
         turn_state.thread_id = Some(thread_id);
         turn_state.num_input_images = Some(num_input_images);
         turn_state.resolved_config = Some(input);
-        self.maybe_emit_turn_event(&turn_id, out);
+        self.maybe_emit_turn_event(&turn_id, out).await;
     }
 
-    fn ingest_turn_token_usage(
+    async fn ingest_turn_token_usage(
         &mut self,
         input: TurnTokenUsageFact,
         out: &mut Vec<TrackEventRequest>,
@@ -510,11 +517,12 @@ impl AnalyticsReducer {
             started_at: None,
             token_usage: None,
             completed: None,
+            latest_diff: None,
             steer_count: 0,
         });
         turn_state.thread_id = Some(input.thread_id);
         turn_state.token_usage = Some(input.token_usage);
-        self.maybe_emit_turn_event(&turn_id, out);
+        self.maybe_emit_turn_event(&turn_id, out).await;
     }
 
     async fn ingest_skill_invoked(
@@ -621,7 +629,7 @@ impl AnalyticsReducer {
         });
     }
 
-    fn ingest_response(
+    async fn ingest_response(
         &mut self,
         connection_id: u64,
         response: ClientResponse,
@@ -673,12 +681,13 @@ impl AnalyticsReducer {
                     started_at: None,
                     token_usage: None,
                     completed: None,
+                    latest_diff: None,
                     steer_count: 0,
                 });
                 turn_state.connection_id = Some(connection_id);
                 turn_state.thread_id = Some(pending_request.thread_id);
                 turn_state.num_input_images = Some(pending_request.num_input_images);
-                self.maybe_emit_turn_event(&turn_id, out);
+                self.maybe_emit_turn_event(&turn_id, out).await;
             }
             ClientResponse::TurnSteer {
                 request_id,
@@ -740,7 +749,7 @@ impl AnalyticsReducer {
         );
     }
 
-    fn ingest_notification(
+    async fn ingest_notification(
         &mut self,
         notification: ServerNotification,
         out: &mut Vec<TrackEventRequest>,
@@ -811,6 +820,7 @@ impl AnalyticsReducer {
                     started_at: None,
                     token_usage: None,
                     completed: None,
+                    latest_diff: None,
                     steer_count: 0,
                 });
                 turn_state.started_at = notification
@@ -818,6 +828,24 @@ impl AnalyticsReducer {
                     .started_at
                     .and_then(|started_at| u64::try_from(started_at).ok());
             }
+            ServerNotification::TurnDiffUpdated(notification) => {
+                let turn_state =
+                    self.turns
+                        .entry(notification.turn_id.clone())
+                        .or_insert(TurnState {
+                            connection_id: None,
+                            thread_id: None,
+                            num_input_images: None,
+                            resolved_config: None,
+                            started_at: None,
+                            token_usage: None,
+                            completed: None,
+                            latest_diff: None,
+                            steer_count: 0,
+                        });
+                turn_state.thread_id = Some(notification.thread_id);
+                turn_state.latest_diff = Some(notification.diff);
+            }
             ServerNotification::TurnCompleted(notification) => {
                 let turn_state =
                     self.turns
@@ -830,6 +858,7 @@ impl AnalyticsReducer {
                             started_at: None,
                             token_usage: None,
                             completed: None,
+                            latest_diff: None,
                             steer_count: 0,
                         });
                 turn_state.completed = Some(CompletedTurnState {
@@ -849,7 +878,7 @@ impl AnalyticsReducer {
                         .and_then(|duration_ms| u64::try_from(duration_ms).ok()),
                 });
                 let turn_id = notification.turn.id;
-                self.maybe_emit_turn_event(&turn_id, out);
+                self.maybe_emit_turn_event(&turn_id, out).await;
             }
             _ => {}
         }
@@ -985,7 +1014,7 @@ impl AnalyticsReducer {
         }));
     }
 
-    fn maybe_emit_turn_event(&mut self, turn_id: &str, out: &mut Vec<TrackEventRequest>) {
+    async fn maybe_emit_turn_event(&mut self, turn_id: &str, out: &mut Vec<TrackEventRequest>) {
         let Some(turn_state) = self.turns.get(turn_id) else {
             return;
         };
@@ -1018,18 +1047,23 @@ impl AnalyticsReducer {
             warn_missing_analytics_context(&drop_site, MissingAnalyticsContext::ThreadMetadata);
             return;
         };
-        out.push(TrackEventRequest::TurnEvent(Box::new(
-            CodexTurnEventRequest {
-                event_type: "codex_turn_event",
-                event_params: codex_turn_event_params(
-                    connection_state.app_server_client.clone(),
-                    connection_state.runtime.clone(),
-                    turn_id.to_string(),
-                    turn_state,
-                    thread_metadata,
-                ),
-            },
-        )));
+        let turn_event = TrackEventRequest::TurnEvent(Box::new(CodexTurnEventRequest {
+            event_type: "codex_turn_event",
+            event_params: codex_turn_event_params(
+                connection_state.app_server_client.clone(),
+                connection_state.runtime.clone(),
+                turn_id.to_string(),
+                turn_state,
+                thread_metadata,
+            ),
+        }));
+        let accepted_line_event = accepted_line_event_input(turn_id, turn_state);
+
+        out.push(turn_event);
+        if let Some((mut input, cwd)) = accepted_line_event {
+            input.repo_hash = accepted_line_repo_hash_for_cwd(cwd.as_path()).await;
+            out.extend(accepted_line_fingerprint_event_requests(input));
+        }
         self.turns.remove(turn_id);
     }
 
@@ -1641,6 +1675,36 @@ fn web_search_query_count(query: &str, action: Option<&WebSearchAction>) -> Opti
     }
 }
 
+fn accepted_line_event_input(
+    turn_id: &str,
+    turn_state: &TurnState,
+) -> Option<(AcceptedLineFingerprintEventInput, PathBuf)> {
+    let latest_diff = turn_state.latest_diff.as_deref()?;
+    let summary = accepted_line_fingerprints_from_unified_diff(latest_diff);
+    if summary.accepted_added_lines == 0 && summary.accepted_deleted_lines == 0 {
+        return None;
+    }
+
+    let thread_id = turn_state.thread_id.clone()?;
+    let resolved_config = turn_state.resolved_config.clone()?;
+
+    Some((
+        AcceptedLineFingerprintEventInput {
+            event_type: "codex.accepted_line_fingerprints",
+            turn_id: turn_id.to_string(),
+            thread_id,
+            product_surface: Some("codex".to_string()),
+            model_slug: Some(resolved_config.model.clone()),
+            completed_at: now_unix_seconds(),
+            repo_hash: None,
+            accepted_added_lines: summary.accepted_added_lines,
+            accepted_deleted_lines: summary.accepted_deleted_lines,
+            line_fingerprints: summary.line_fingerprints,
+        },
+        resolved_config.permission_profile_cwd,
+    ))
+}
+
 fn codex_turn_event_params(
     app_server_client: CodexAppServerClientMetadata,
     runtime: CodexRuntimeMetadata,
diff --git a/codex-rs/git-utils/src/info.rs b/codex-rs/git-utils/src/info.rs
index 067dd15869..c6656b8fa5 100644
--- a/codex-rs/git-utils/src/info.rs
+++ b/codex-rs/git-utils/src/info.rs
@@ -158,6 +158,108 @@ pub async fn get_head_commit_hash(cwd: &Path) -> Option<GitSha> {
     }
 }
 
+pub fn canonicalize_git_remote_url(url: &str) -> Option<String> {
+    let url = trim_git_suffix(url.trim().trim_end_matches('/'));
+    if url.is_empty() {
+        return None;
+    }
+
+    if let Some((scheme, rest)) = url.split_once("://") {
+        return canonicalize_git_url_like_remote(scheme, rest);
+    }
+
+    if let Some((host_part, path)) = parse_scp_like_remote(url) {
+        return canonicalize_git_remote_host_path(host_part, path, /*default_port*/ None);
+    }
+
+    let (host_part, path) = url.split_once('/')?;
+    canonicalize_git_remote_host_path(host_part, path, /*default_port*/ None)
+}
+
+fn canonicalize_git_url_like_remote(scheme: &str, rest: &str) -> Option<String> {
+    let default_port = match scheme {
+        "git" => Some("9418"),
+        "http" => Some("80"),
+        "https" => Some("443"),
+        "ssh" => Some("22"),
+        _ => return None,
+    };
+
+    let rest = rest
+        .find(['?', '#'])
+        .map_or(rest, |suffix_index| &rest[..suffix_index]);
+    let (host_part, path) = rest.split_once('/')?;
+    canonicalize_git_remote_host_path(host_part, path, default_port)
+}
+
+fn parse_scp_like_remote(remote: &str) -> Option<(&str, &str)> {
+    if remote.contains('/')
+        && remote
+            .find('/')
+            .is_some_and(|slash| remote.find(':').is_none_or(|colon| slash < colon))
+    {
+        return None;
+    }
+
+    let (host_part, path) = remote.split_once(':')?;
+    if host_part.is_empty() || path.is_empty() {
+        return None;
+    }
+    Some((host_part, path))
+}
+
+fn canonicalize_git_remote_host_path(
+    host_part: &str,
+    path: &str,
+    default_port: Option<&str>,
+) -> Option<String> {
+    let host = normalize_remote_host(
+        host_part
+            .rsplit_once('@')
+            .map_or(host_part, |(_, host)| host)
+            .trim()
+            .trim_end_matches('/'),
+        default_port,
+    );
+    if host.is_empty() {
+        return None;
+    }
+
+    let path = trim_git_suffix(path.trim().trim_matches('/'));
+    let components = path
+        .split('/')
+        .filter(|component| !component.is_empty())
+        .collect::<Vec<_>>();
+    let [owner, repo, ..] = components.as_slice() else {
+        return None;
+    };
+    if matches!((*owner, *repo), ("." | "..", _) | (_, "." | "..")) {
+        return None;
+    }
+    let path = components.join("/");
+
+    if host == "github.com" {
+        Some(format!("{host}/{}", path.to_ascii_lowercase()))
+    } else {
+        Some(format!("{host}/{path}"))
+    }
+}
+
+fn normalize_remote_host(host: &str, default_port: Option<&str>) -> String {
+    let host = host.to_ascii_lowercase();
+    if let Some(default_port) = default_port
+        && let Some((host_without_port, port)) = host.rsplit_once(':')
+        && port == default_port
+    {
+        return host_without_port.to_string();
+    }
+    host
+}
+
+fn trim_git_suffix(value: &str) -> &str {
+    value.strip_suffix(".git").unwrap_or(value)
+}
+
 pub async fn get_has_changes(cwd: &Path) -> Option<bool> {
     let output = run_git_command_with_timeout(&["status", "--porcelain"], cwd).await?;
     if !output.status.success() {
@@ -724,3 +826,46 @@ pub async fn current_branch_name(cwd: &Path) -> Option<String> {
         .map(|s| s.trim().to_string())
         .filter(|name| !name.is_empty())
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use pretty_assertions::assert_eq;
+
+    #[test]
+    fn canonicalize_git_remote_url_normalizes_github_variants() {
+        for remote in [
+            "git@github.com:OpenAI/Codex.git",
+            "ssh://git@github.com/openai/codex.git",
+            "ssh://git@github.com:22/OpenAI/Codex.git",
+            "https://github.com/openai/codex.git",
+            "https://github.com:443/openai/codex.git",
+            "https://token@github.com/openai/codex/",
+            "github.com/OpenAI/Codex.git",
+        ] {
+            assert_eq!(
+                canonicalize_git_remote_url(remote),
+                Some("github.com/openai/codex".to_string())
+            );
+        }
+    }
+
+    #[test]
+    fn canonicalize_git_remote_url_handles_ghe_without_lowercasing_path() {
+        assert_eq!(
+            canonicalize_git_remote_url("git@ghe.company.com:Org/Repo.git"),
+            Some("ghe.company.com/Org/Repo".to_string())
+        );
+        assert_eq!(
+            canonicalize_git_remote_url("ssh://git@ghe.company.com:2222/Org/Repo.git"),
+            Some("ghe.company.com:2222/Org/Repo".to_string())
+        );
+    }
+
+    #[test]
+    fn canonicalize_git_remote_url_rejects_non_repository_values() {
+        for remote in ["", "file:///tmp/repo", "github.com/openai", "/tmp/repo"] {
+            assert_eq!(canonicalize_git_remote_url(remote), None);
+        }
+    }
+}
diff --git a/codex-rs/git-utils/src/lib.rs b/codex-rs/git-utils/src/lib.rs
index 63eaf586d5..bcd1a8b5c9 100644
--- a/codex-rs/git-utils/src/lib.rs
+++ b/codex-rs/git-utils/src/lib.rs
@@ -24,6 +24,7 @@ pub use errors::GitToolingError;
 pub use info::CommitLogEntry;
 pub use info::GitDiffToRemote;
 pub use info::GitInfo;
+pub use info::canonicalize_git_remote_url;
 pub use info::collect_git_info;
 pub use info::current_branch_name;
 pub use info::default_branch_name;