From 6fe44104f3c450361abb721a3586cc177ae95bba Mon Sep 17 00:00:00 2001
From: Eric Traut <etraut@openai.com>
Date: Fri, 10 Apr 2026 20:59:16 -0700
Subject: [PATCH] codex: restore timers after resume history replay (#17380)

---
 codex-rs/core/src/codex.rs          |   3 +-
 codex-rs/core/tests/suite/timers.rs | 107 ++++++++++++++++++++++++++++
 2 files changed, 108 insertions(+), 2 deletions(-)

diff --git a/codex-rs/core/src/codex.rs b/codex-rs/core/src/codex.rs
index 682d96fef9..dbc76e2548 100644
--- a/codex-rs/core/src/codex.rs
+++ b/codex-rs/core/src/codex.rs
@@ -2137,8 +2137,6 @@ impl Session {
         for event in events {
             sess.send_event_raw(event).await;
         }
-        sess.restore_timers_from_db().await;
-
         // Start the watcher after SessionConfigured so it cannot emit earlier events.
         sess.start_skills_watcher_listener();
         // Construct sandbox_state before MCP startup so it can be sent to each
@@ -2233,6 +2231,7 @@ impl Session {
             let mut state = sess.state.lock().await;
             state.set_pending_session_start_source(Some(session_start_source));
         }
+        sess.restore_timers_from_db().await;
 
         memories::start_memories_startup_task(
             &sess,
diff --git a/codex-rs/core/tests/suite/timers.rs b/codex-rs/core/tests/suite/timers.rs
index 2ec532e108..e899fe7ae3 100644
--- a/codex-rs/core/tests/suite/timers.rs
+++ b/codex-rs/core/tests/suite/timers.rs
@@ -8,6 +8,7 @@ use codex_core::timers::ThreadTimerTrigger;
 use codex_core::timers::TimerDelivery;
 use codex_features::Feature;
 use codex_protocol::protocol::EventMsg;
+use codex_protocol::protocol::Op;
 use core_test_support::responses::ev_assistant_message;
 use core_test_support::responses::ev_completed;
 use core_test_support::responses::ev_response_created;
@@ -184,6 +185,112 @@ async fn create_timer_rejects_ephemeral_thread() -> Result<()> {
     Ok(())
 }
 
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn resume_due_timer_runs_after_history_reconstruction() -> Result<()> {
+    let server = start_mock_server().await;
+    let mock = mount_sse_sequence(
+        &server,
+        vec![
+            sse(vec![
+                ev_response_created("resp-1"),
+                ev_assistant_message("msg-1", "recorded before resume"),
+                ev_completed("resp-1"),
+            ]),
+            sse(vec![
+                ev_response_created("resp-2"),
+                ev_assistant_message("msg-2", "timer after resume"),
+                ev_completed("resp-2"),
+            ]),
+        ],
+    )
+    .await;
+
+    let mut builder = test_codex().with_config(|config| {
+        config
+            .features
+            .enable(Feature::Timers)
+            .unwrap_or_else(|err| panic!("test config should allow feature update: {err}"));
+        config
+            .features
+            .enable(Feature::Sqlite)
+            .unwrap_or_else(|err| panic!("test config should allow feature update: {err}"));
+    });
+    let initial = builder.build(&server).await?;
+    initial.submit_turn("context before resume").await?;
+
+    let db = initial.codex.state_db().expect("state db enabled");
+    let home = initial.home.clone();
+    let rollout_path = initial
+        .codex
+        .rollout_path()
+        .expect("rollout path should be materialized");
+    let thread_id = initial.session_configured.session_id.to_string();
+
+    initial.codex.submit(Op::Shutdown).await?;
+    wait_for_event(&initial.codex, |event| {
+        matches!(event, EventMsg::ShutdownComplete)
+    })
+    .await;
+
+    let now = Utc::now().timestamp();
+    db.create_thread_timer(&codex_state::ThreadTimerCreateParams {
+        id: "resume-due-timer".to_string(),
+        thread_id,
+        source: "external".to_string(),
+        client_id: "codex-test".to_string(),
+        trigger_json: r#"{"kind":"delay","seconds":0,"repeat":false}"#.to_string(),
+        content: "resume timer".to_string(),
+        instructions: None,
+        meta_json: "{}".to_string(),
+        delivery: TimerDelivery::AfterTurn.as_str().to_string(),
+        created_at: now - 10,
+        next_run_at: Some(now - 1),
+        last_run_at: None,
+        pending_run: false,
+    })
+    .await?;
+
+    let mut resume_builder = test_codex().with_config(|config| {
+        config
+            .features
+            .enable(Feature::Timers)
+            .unwrap_or_else(|err| panic!("test config should allow feature update: {err}"));
+        config
+            .features
+            .enable(Feature::Sqlite)
+            .unwrap_or_else(|err| panic!("test config should allow feature update: {err}"));
+    });
+    let resumed = resume_builder.resume(&server, home, rollout_path).await?;
+
+    wait_for_event_with_timeout(
+        &resumed.codex,
+        |event| match event {
+            EventMsg::InjectedMessage(event) => {
+                event.source == "timer resume-due-timer"
+                    && event.content == "Timer fired: resume timer"
+            }
+            _ => false,
+        },
+        Duration::from_secs(20),
+    )
+    .await;
+    wait_for_event_with_timeout(
+        &resumed.codex,
+        |event| matches!(event, EventMsg::TurnComplete(_)),
+        Duration::from_secs(20),
+    )
+    .await;
+
+    let requests = mock.requests();
+    assert_eq!(requests.len(), 2);
+    let resumed_request = &requests[1];
+    assert!(resumed_request.body_contains_text("context before resume"));
+    assert!(resumed_request.body_contains_text("recorded before resume"));
+    assert!(resumed_request.body_contains_text("Timer fired: resume timer"));
+
+    Ok(())
+}
+
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
 async fn list_timers_discovers_externally_inserted_timer() -> Result<()> {
     let server = start_mock_server().await;