From 840d6b52795adbefec6d155f8674751372f870bd Mon Sep 17 00:00:00 2001
From: macodev00 <273427913+macodev00@users.noreply.github.com>
Date: Sun, 20 Sep 2026 08:18:04 +0000
Subject: [PATCH] fix(relay): deliver Live Activity updates on phase change

starting to running keeps activeCount at 1 and is not attention or terminal,
so the 15s Live Activity throttle dropped the running push and the lock
screen stayed on Connecting. Exempt observed phase changes from that
window. Timestamp and ordering churn stay throttled.
---
 .../src/agentActivity/ApnsDeliveries.test.ts  | 70 +++++++++++++++++++
 .../relay/src/agentActivity/ApnsDeliveries.ts | 18 +++++
 2 files changed, 88 insertions(+)

diff --git a/infra/relay/src/agentActivity/ApnsDeliveries.test.ts b/infra/relay/src/agentActivity/ApnsDeliveries.test.ts
index e98c2b639598..a636a7004d44 100644
--- a/infra/relay/src/agentActivity/ApnsDeliveries.test.ts
+++ b/infra/relay/src/agentActivity/ApnsDeliveries.test.ts
@@ -650,6 +650,76 @@ describe("ApnsDeliveries", () => {
     },
   );
 
+  it.effect(
+    "queues an update when phase changes from starting to running inside the throttle window",
+    () => {
+      const attempts: Array<DeliveryAttempts.DeliveryAttemptInput> = [];
+      const queuedJobs: Array<SignedApnsDeliveryJob> = [];
+      const startingAggregate: RelayAgentActivityAggregateState = {
+        ...aggregate,
+        activities: [
+          {
+            ...aggregate.activities[0]!,
+            phase: "starting",
+            status: "Connecting",
+          },
+        ],
+      };
+      const runningAggregate: RelayAgentActivityAggregateState = {
+        ...startingAggregate,
+        updatedAt: "1970-01-01T00:00:04.000Z",
+        activities: [
+          {
+            ...startingAggregate.activities[0]!,
+            phase: "running",
+            status: "Working",
+            updatedAt: "1970-01-01T00:00:04.000Z",
+          },
+        ],
+      };
+
+      return Effect.gen(function* () {
+        const deliveries = yield* ApnsDeliveries.ApnsDeliveries;
+        const first = yield* deliveries.sendForTarget({
+          target,
+          aggregate: startingAggregate,
+          nowMs: 0,
+        });
+        expect(first?.kind).toBe("live_activity_update");
+
+        const second = yield* deliveries.sendForTarget({
+          target: {
+            ...target,
+            last_aggregate_json: JSON.stringify(startingAggregate),
+            last_live_activity_delivery_at: "1970-01-01T00:00:00.000Z",
+          },
+          aggregate: runningAggregate,
+          nowMs: 4_000,
+        });
+
+        expect(second?.kind).toBe("live_activity_update");
+        expect(queuedJobs).toMatchObject([
+          {
+            payload: {
+              kind: "live_activity_update",
+              target: {
+                token: "activity-token",
+              },
+            },
+          },
+          {
+            payload: {
+              kind: "live_activity_update",
+              target: {
+                token: "activity-token",
+              },
+            },
+          },
+        ]);
+      }).pipe(Effect.provide(makeLayer({ attempts, queuedJobs })));
+    },
+  );
+
   it.effect("queues an end for an active Live Activity when Live Activities are disabled", () => {
     const attempts: Array<DeliveryAttempts.DeliveryAttemptInput> = [];
     const queuedJobs: Array<SignedApnsDeliveryJob> = [];
diff --git a/infra/relay/src/agentActivity/ApnsDeliveries.ts b/infra/relay/src/agentActivity/ApnsDeliveries.ts
index 651f031f0efa..e19f9569c118 100644
--- a/infra/relay/src/agentActivity/ApnsDeliveries.ts
+++ b/infra/relay/src/agentActivity/ApnsDeliveries.ts
@@ -160,6 +160,19 @@ function aggregateNeedsAttention(aggregate: RelayAgentActivityAggregateState): b
   );
 }
 
+function aggregateHasPhaseChange(
+  previous: RelayAgentActivityAggregateState,
+  next: RelayAgentActivityAggregateState,
+): boolean {
+  const previousPhases = new Map(
+    previous.activities.map((row) => [`${row.environmentId}\0${row.threadId}`, row.phase]),
+  );
+  return next.activities.some((row) => {
+    const previousPhase = previousPhases.get(`${row.environmentId}\0${row.threadId}`);
+    return previousPhase !== undefined && previousPhase !== row.phase;
+  });
+}
+
 function shouldUpdateLiveActivity(input: {
   readonly previousAggregate: RelayAgentActivityAggregateState | null;
   readonly nextAggregate: RelayAgentActivityAggregateState;
@@ -184,6 +197,11 @@ function shouldUpdateLiveActivity(input: {
   if (newlyTerminalRows(input.previousAggregate, input.nextAggregate, true).length > 0) {
     return true;
   }
+  // starting→running keeps activeCount at 1 and is not attention/terminal, but
+  // the lock-screen copy changes (Connecting→Working) and is never republished.
+  if (aggregateHasPhaseChange(input.previousAggregate, input.nextAggregate)) {
+    return true;
+  }
   const lastDeliveryAtMs =
     input.lastDeliveryAt === null
       ? null