diff --git a/libs/tests/conftest.py b/libs/tests/conftest.py
new file mode 100644
index 00000000..71eee222
--- /dev/null
+++ b/libs/tests/conftest.py
@@ -0,0 +1,29 @@
+"""Global test configuration for all tests.
+
+This conftest.py is at the root of the tests directory and applies to all test modules.
+"""
+
+import os
+
+import pytest
+
+
+@pytest.fixture(autouse=True)
+def disable_usage_tracking():
+    """Disable CLI usage tracking for all tests.
+
+    This prevents test runs from sending analytics events to PostHog.
+    The fixture is autouse=True so it applies automatically to every test.
+    """
+    original_value = os.environ.get("ARCADE_USAGE_TRACKING")
+
+    # Disable tracking
+    os.environ["ARCADE_USAGE_TRACKING"] = "0"
+
+    yield
+
+    # Restore original value after test
+    if original_value is None:
+        os.environ.pop("ARCADE_USAGE_TRACKING", None)
+    else:
+        os.environ["ARCADE_USAGE_TRACKING"] = original_value