diff --git a/py/src/braintrust/devserver/server.py b/py/src/braintrust/devserver/server.py
index a141fc79..90ceb2e8 100644
--- a/py/src/braintrust/devserver/server.py
+++ b/py/src/braintrust/devserver/server.py
@@ -370,6 +370,8 @@ def scorer_fn(input, output, expected, metadata):
             "strict": True,
         }
         headers = {"Accept": "application/json"}
+        if state.org_name:
+            headers["x-bt-org-name"] = state.org_name
         if project_id:
             headers["x-bt-project-id"] = project_id
         result = state.proxy_conn().post("function/invoke", json=request, headers=headers)
diff --git a/py/src/braintrust/devserver/test_server.py b/py/src/braintrust/devserver/test_server.py
new file mode 100644
index 00000000..b983e47d
--- /dev/null
+++ b/py/src/braintrust/devserver/test_server.py
@@ -0,0 +1,30 @@
+from unittest.mock import MagicMock
+
+import pytest
+from braintrust.test_helpers import has_devserver_installed
+
+
+def test_ui_scorer_forwards_org_name_to_function_invoke():
+    if not has_devserver_installed():
+        pytest.skip("Devserver dependencies not installed (requires .[cli])")
+
+    from braintrust.devserver.server import make_scorer
+
+    response = MagicMock()
+    response.json.return_value = {"score": 1}
+    connection = MagicMock()
+    connection.post.return_value = response
+    state = MagicMock()
+    state.org_name = "test-org"
+    state.proxy_conn.return_value = connection
+    state.current_span.get.return_value.export.return_value = {}
+
+    scorer = make_scorer(state, "ui-scorer", {"function_id": "function-id"}, "project-id")
+
+    assert scorer("input", "output", "expected", {}) == {"score": 1}
+    assert connection.post.call_args.args == ("function/invoke",)
+    assert connection.post.call_args.kwargs["headers"] == {
+        "Accept": "application/json",
+        "x-bt-org-name": "test-org",
+        "x-bt-project-id": "project-id",
+    }