diff --git a/agents/core-logic/requirements.txt b/agents/core-logic/requirements.txt
index 92106db..06d3fe4 100644
--- a/agents/core-logic/requirements.txt
+++ b/agents/core-logic/requirements.txt
@@ -10,6 +10,7 @@ google-cloud-secret-manager>=2.20.0
 # MCP toolset
 httpx>=0.27.0
 google-auth>=2.29.0
+google-auth-oauthlib>=1.2.0
 google-auth-httplib2>=0.2.0
 
 # Observability