diff --git a/content/ja/docs/concepts/instrumentation/_index.md b/content/ja/docs/concepts/instrumentation/_index.md
index e9f06bca09a9..e61747d1fadd 100644
--- a/content/ja/docs/concepts/instrumentation/_index.md
+++ b/content/ja/docs/concepts/instrumentation/_index.md
@@ -3,6 +3,7 @@ title: 計装
 description: OpenTelemetryはどのように計装を促進するか
 weight: 15
 default_lang_commit: 94d77ab8cbfe5552a7cd68bf677be86c574a613a
+drifted_from_default: true
 ---
 
 システムを[観測可能][observable]にするため、システムが **計装** されなければなりません。
diff --git a/data/registry/extension-java-auth-gcp.yml b/data/registry/extension-java-auth-gcp.yml
new file mode 100644
index 000000000000..789a18f05d13
--- /dev/null
+++ b/data/registry/extension-java-auth-gcp.yml
@@ -0,0 +1,21 @@
+title: Google Cloud Auth Extension
+registryType: extension
+language: java
+tags:
+  - gcp
+  - extension
+  - java
+  - auth
+  - google
+license: Apache 2.0
+description:
+  This extension provides automatic Google Cloud authentication for
+  OpenTelemetry Java's OTLP exporters, enabling telemetry export to Google Cloud
+  for both zero-code and manual instrumentation setups.
+authors:
+  - name: OpenTelemetry Authors
+urls:
+  repo: https://github.com/open-telemetry/opentelemetry-java-contrib/tree/main/gcp-auth-extension
+createdAt: 2025-03-18
+isNative: false
+isFirstParty: false
diff --git a/static/refcache.json b/static/refcache.json
index 2ffa7ee46e16..94d6b2c0e7c5 100644
--- a/static/refcache.json
+++ b/static/refcache.json
@@ -7691,6 +7691,10 @@
     "StatusCode": 206,
     "LastSeen": "2025-01-16T11:37:38.952312-05:00"
   },
+  "https://github.com/open-telemetry/opentelemetry-java-contrib/tree/main/gcp-auth-extension": {
+    "StatusCode": 206,
+    "LastSeen": "2025-03-18T17:25:06.959055345Z"
+  },
   "https://github.com/open-telemetry/opentelemetry-java-contrib/tree/main/gcp-resources": {
     "StatusCode": 206,
     "LastSeen": "2025-01-16T11:37:39.709614-05:00"