diff --git a/.python-version b/.python-version
index e4fba21..24ee5b1 100644
--- a/.python-version
+++ b/.python-version
@@ -1 +1 @@
-3.12
+3.13
diff --git a/requirements.txt b/requirements.txt
index 92106db..4c95319 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -4,6 +4,9 @@
 google-adk>=1.0.0,<2.0.0
 google-cloud-aiplatform[adk,agent_engines,evaluation]>=1.112.0
 
+# litellm — pinned for Python 3.13 compatibility
+litellm>=1.67.0
+
 # Secret Manager integration
 google-cloud-secret-manager>=2.20.0