diff --git a/src/lock-ops.mjs b/src/lock-ops.mjs
index 32891b6..ad8fef3 100644
--- a/src/lock-ops.mjs
+++ b/src/lock-ops.mjs
@@ -8,7 +8,7 @@ import {
   KIND_APP_DATA,
   MS_PER_SECOND,
 } from './constants.mjs';
-import { nowUnix } from './utils.mjs';
+import { nowUnix, relayListLabel } from './utils.mjs';
 import { defaultHealthManager, buildRelayHealthConfig, RelayHealthManager } from './relay-health-manager.mjs';
 import { publishLock, LockPublisher, secureRandom } from './lock-publisher.mjs';
 
@@ -65,10 +65,6 @@ function withTimeout(promise, timeoutMs, timeoutMessage) {
   });
 }
 
-function relayListLabel(relays) {
-  return relays.join(', ');
-}
-
 function mergeRelayList(primaryRelays, fallbackRelays) {
   return [...new Set([...primaryRelays, ...fallbackRelays])];
 }
diff --git a/src/lock-publisher.mjs b/src/lock-publisher.mjs
index b506f1b..c55ed5b 100644
--- a/src/lock-publisher.mjs
+++ b/src/lock-publisher.mjs
@@ -7,6 +7,7 @@ import {
   getMinActiveRelayPool,
 } from './torch-config.mjs';
 import { defaultHealthManager, buildRelayHealthConfig } from './relay-health-manager.mjs';
+import { relayListLabel } from './utils.mjs';
 
 function withTimeout(promise, timeoutMs, timeoutMessage) {
   let timeoutHandle;
@@ -18,10 +19,6 @@ function withTimeout(promise, timeoutMs, timeoutMessage) {
   });
 }
 
-function relayListLabel(relays) {
-  return relays.join(', ');
-}
-
 function mergeRelayList(primaryRelays, fallbackRelays) {
   return [...new Set([...primaryRelays, ...fallbackRelays])];
 }
diff --git a/src/lock-utils.mjs b/src/lock-utils.mjs
index cac3fdc..3cd93f8 100644
--- a/src/lock-utils.mjs
+++ b/src/lock-utils.mjs
@@ -2,6 +2,8 @@ import fs from 'node:fs/promises';
 import path from 'node:path';
 import { todayDateStr, getIsoWeekStr } from './utils.mjs';
 
+export { relayListLabel } from './utils.mjs';
+
 /**
  * Scans the local log directory to identify agents that have already completed their task
  * for the current period (daily or weekly).
@@ -58,10 +60,6 @@ export function withTimeout(promise, timeoutMs, timeoutMessage) {
   });
 }
 
-export function relayListLabel(relays) {
-  return relays.join(', ');
-}
-
 export function mergeRelayList(primaryRelays, fallbackRelays) {
   return [...new Set([...primaryRelays, ...fallbackRelays])];
 }
diff --git a/src/utils.mjs b/src/utils.mjs
index af844e2..fde05f0 100644
--- a/src/utils.mjs
+++ b/src/utils.mjs
@@ -47,3 +47,7 @@ export function ensureDir(dir) {
     fs.mkdirSync(dir, { recursive: true });
   }
 }
+
+export function relayListLabel(relays) {
+  return relays.join(', ');
+}
diff --git a/test/utils.test.mjs b/test/utils.test.mjs
index b2d2785..6229cb5 100644
--- a/test/utils.test.mjs
+++ b/test/utils.test.mjs
@@ -2,7 +2,7 @@ import { describe, it, after } from 'node:test';
 import assert from 'node:assert';
 import fs from 'node:fs';
 import path from 'node:path';
-import { getIsoWeekStr, todayDateStr, nowUnix, ensureDir, detectPlatform } from '../src/utils.mjs';
+import { getIsoWeekStr, todayDateStr, nowUnix, ensureDir, detectPlatform, relayListLabel } from '../src/utils.mjs';
 
 describe('Date Utilities', () => {
   describe('todayDateStr', () => {
@@ -184,3 +184,22 @@ describe('File Utilities', () => {
     });
   });
 });
+
+describe('String Utilities', () => {
+  describe('relayListLabel', () => {
+    it('joins relay URLs with comma and space', () => {
+      const relays = ['ws://relay1.com', 'ws://relay2.com'];
+      assert.strictEqual(relayListLabel(relays), 'ws://relay1.com, ws://relay2.com');
+    });
+
+    it('handles single relay', () => {
+      const relays = ['ws://relay1.com'];
+      assert.strictEqual(relayListLabel(relays), 'ws://relay1.com');
+    });
+
+    it('handles empty array', () => {
+      const relays = [];
+      assert.strictEqual(relayListLabel(relays), '');
+    });
+  });
+});