From 0843d9af58d41b0f7e29229b7f5011e927dbc7d7 Mon Sep 17 00:00:00 2001
From: "N. Taylor Mullen" <ntaylormullen@google.com>
Date: Mon, 22 Dec 2025 12:45:33 -0800
Subject: [PATCH] fix(core): use debugLogger.debug for startup profiler logs
 (#15443)

---
 .../core/src/telemetry/startupProfiler.test.ts     | 14 ++++++++++++++
 packages/core/src/telemetry/startupProfiler.ts     |  6 +++---
 2 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/packages/core/src/telemetry/startupProfiler.test.ts b/packages/core/src/telemetry/startupProfiler.test.ts
index ff22abda62..2898cf4cce 100644
--- a/packages/core/src/telemetry/startupProfiler.test.ts
+++ b/packages/core/src/telemetry/startupProfiler.test.ts
@@ -7,6 +7,7 @@
 import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest';
 import { StartupProfiler } from './startupProfiler.js';
 import type { Config } from '../config/config.js';
+import { debugLogger } from '../utils/debugLogger.js';
 
 // Mock the metrics module
 vi.mock('./metrics.js', () => ({
@@ -255,6 +256,19 @@ describe('StartupProfiler', () => {
         }),
       );
     });
+
+    it('should use debug logging instead of standard logging', () => {
+      const logSpy = vi.spyOn(debugLogger, 'log');
+      const debugSpy = vi.spyOn(debugLogger, 'debug');
+
+      const handle = profiler.start('test_phase');
+      handle?.end();
+
+      profiler.flush(mockConfig);
+
+      expect(logSpy).not.toHaveBeenCalled();
+      expect(debugSpy).toHaveBeenCalled();
+    });
   });
 
   describe('integration scenarios', () => {
diff --git a/packages/core/src/telemetry/startupProfiler.ts b/packages/core/src/telemetry/startupProfiler.ts
index 07776cfe36..89421380b7 100644
--- a/packages/core/src/telemetry/startupProfiler.ts
+++ b/packages/core/src/telemetry/startupProfiler.ts
@@ -145,7 +145,7 @@ export class StartupProfiler {
    * Flushes buffered metrics to the telemetry system.
    */
   flush(config: Config): void {
-    debugLogger.log(
+    debugLogger.debug(
       '[STARTUP] StartupProfiler.flush() called with',
       this.phases.size,
       'phases',
@@ -181,7 +181,7 @@ export class StartupProfiler {
           ...phase.details,
         };
 
-        debugLogger.log(
+        debugLogger.debug(
           '[STARTUP] Recording metric for phase:',
           phase.name,
           'duration:',
@@ -192,7 +192,7 @@ export class StartupProfiler {
           details,
         });
       } else {
-        debugLogger.log(
+        debugLogger.debug(
           '[STARTUP] Skipping phase without measure:',
           phase.name,
         );