From 526c9a2b570d1eb4cfbbb23ca07f638be7bf8060 Mon Sep 17 00:00:00 2001
From: Andrew Yuan <Andrew.Yuan@temporal.io>
Date: Tue, 9 Dec 2025 10:58:20 -0500
Subject: [PATCH 1/3] add comments

---
 temporal/api/workflowservice/v1/request_response.proto | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/temporal/api/workflowservice/v1/request_response.proto b/temporal/api/workflowservice/v1/request_response.proto
index 69b673c81..a8d8ac9d8 100644
--- a/temporal/api/workflowservice/v1/request_response.proto
+++ b/temporal/api/workflowservice/v1/request_response.proto
@@ -999,10 +999,15 @@ message ResetStickyTaskQueueResponse {
 
 message ShutdownWorkerRequest {
     string namespace = 1;
+    // sticky_task_queue may not always be populated. We want to ensure all workers
+    // send a shutdown request to update worker state for heartbeating, as well
+    // as cancel pending poll calls early, instead of waiting for timeouts.
     string sticky_task_queue = 2;
     string identity = 3;
     string reason = 4;
 
+    // WorkerHeartbeat contains a list of Worker Instance Keys for all workers
+    // that are shutting down.
     temporal.api.worker.v1.WorkerHeartbeat worker_heartbeat = 5;
 }
 

From eb9b3215b2c50d89ffcf04dc327d321ec1e1da39 Mon Sep 17 00:00:00 2001
From: Andrew Yuan <Andrew.Yuan@temporal.io>
Date: Wed, 10 Dec 2025 12:45:47 -0500
Subject: [PATCH 2/3] Add new worker_instance_key field

---
 temporal/api/workflowservice/v1/request_response.proto | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/temporal/api/workflowservice/v1/request_response.proto b/temporal/api/workflowservice/v1/request_response.proto
index a8d8ac9d8..ae29d8554 100644
--- a/temporal/api/workflowservice/v1/request_response.proto
+++ b/temporal/api/workflowservice/v1/request_response.proto
@@ -1005,10 +1005,11 @@ message ShutdownWorkerRequest {
     string sticky_task_queue = 2;
     string identity = 3;
     string reason = 4;
-
-    // WorkerHeartbeat contains a list of Worker Instance Keys for all workers
-    // that are shutting down.
     temporal.api.worker.v1.WorkerHeartbeat worker_heartbeat = 5;
+    // Technically this is also sent in the WorkerHeartbeat, but
+    // since worker heartbeating can be turned off, this needs
+    // to be a separate, top-level field.
+    string worker_instance_key = 6;
 }
 
 message ShutdownWorkerResponse {

From b6c0b5352453e65fc7d12ea242e1109a37e9d035 Mon Sep 17 00:00:00 2001
From: Andrew Yuan <Andrew.Yuan@temporal.io>
Date: Thu, 22 Jan 2026 11:38:39 -0800
Subject: [PATCH 3/3] add worker_instance_key fields to poll calls

---
 temporal/api/workflowservice/v1/request_response.proto | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/temporal/api/workflowservice/v1/request_response.proto b/temporal/api/workflowservice/v1/request_response.proto
index ae29d8554..aba42496d 100644
--- a/temporal/api/workflowservice/v1/request_response.proto
+++ b/temporal/api/workflowservice/v1/request_response.proto
@@ -269,6 +269,8 @@ message PollWorkflowTaskQueueRequest {
     // Worker deployment options that user has set in the worker.
     // Experimental. Worker Deployments are experimental and might significantly change in the future.
     temporal.api.deployment.v1.WorkerDeploymentOptions deployment_options = 6;
+    // A unique key for this worker instance, used for tracking worker lifecycle.
+    string worker_instance_key = 7;
 }
 
 message PollWorkflowTaskQueueResponse {
@@ -440,6 +442,8 @@ message PollActivityTaskQueueRequest {
     temporal.api.common.v1.WorkerVersionCapabilities worker_version_capabilities = 5 [deprecated = true];
     // Worker deployment options that user has set in the worker.
     temporal.api.deployment.v1.WorkerDeploymentOptions deployment_options = 6;
+    // A unique key for this worker instance, used for tracking worker lifecycle.
+    string worker_instance_key = 7;
 }
 
 message PollActivityTaskQueueResponse {
@@ -1767,6 +1771,8 @@ message PollWorkflowExecutionUpdateRequest {
     // Specifies client's intent to wait for Update results.
     // Omit to request a non-blocking poll.
     temporal.api.update.v1.WaitPolicy wait_policy = 4;
+    // A unique key for this worker instance, used for tracking worker lifecycle.
+    string worker_instance_key = 8;
 }
 
 message PollWorkflowExecutionUpdateResponse {
@@ -1805,6 +1811,8 @@ message PollNexusTaskQueueRequest {
 
     // Worker info to be sent to the server.
     repeated temporal.api.worker.v1.WorkerHeartbeat worker_heartbeat = 7;
+    // A unique key for this worker instance, used for tracking worker lifecycle.
+    string worker_instance_key = 8;
 }
 
 message PollNexusTaskQueueResponse {