fix env parsing

libs/cli/langgraph_cli/cli.py

@@ -93,7 +93,8 @@ def _parse_env_from_config(
 ) -> dict[str, str]:
     """Resolve env vars from langgraph.json 'env' field or a .env fallback."""
     env_field = config_json.get("env")
-    if isinstance(env_field, dict):
+    # validate_config_file will default env to {}
+    if isinstance(env_field, dict) and env_field:
         return {str(k): str(v) for k, v in env_field.items()}
     if isinstance(env_field, str):
         env_path = (config_path.parent / env_field).resolve()

libs/cli/tests/unit_tests/test_deploy_helpers.py

@@ -104,6 +104,16 @@ class TestParseEnvFromConfig:
         result = _parse_env_from_config({}, config_path)
         assert result == {"DEFAULT_KEY": "default_val"}
 
+    def test_env_empty_dict_falls_back_to_dotenv(self, tmp_path, monkeypatch):
+        """validate_config defaults env to {}, should still fall back to .env."""
+        env_file = tmp_path / ".env"
+        env_file.write_text("MY_KEY=my_val\n")
+        monkeypatch.chdir(tmp_path)
+        config_path = tmp_path / "langgraph.json"
+        config_path.touch()
+        result = _parse_env_from_config({"env": {}}, config_path)
+        assert result == {"MY_KEY": "my_val"}
+
     def test_env_missing_no_dotenv_returns_empty(self, tmp_path, monkeypatch):
         monkeypatch.chdir(tmp_path)
         config_path = tmp_path / "langgraph.json"