diff --git a/tests/lib/test_credentials.py b/tests/lib/test_credentials.py
index 2c27eda36..27dcc12cb 100644
--- a/tests/lib/test_credentials.py
+++ b/tests/lib/test_credentials.py
@@ -67,6 +67,7 @@
     "ANTHROPIC_SERVICE_ACCOUNT_ID",
     "ANTHROPIC_WORKSPACE_ID",
     "ANTHROPIC_SCOPE",
+    "ANTHROPIC_BASE_URL",
 ]