fresh eyes check

atroposlib/envs/teacher_distillation_env.py

@@ -285,7 +285,7 @@ class TeacherDistillationEnv(BaseEnv, ABC):
         config: TeacherDistillationConfig,
         server_configs: Union[ServerBaseline, List[APIServerConfig]],
         teacher_server_configs: Optional[
-            Union[ServerBaseline, List[APIServerConfig]]
+            Union[ServerBaseline, APIServerConfig, List[APIServerConfig]]
         ] = None,
         slurm: bool = False,
         testing: bool = False,
@@ -302,6 +302,9 @@ class TeacherDistillationEnv(BaseEnv, ABC):
                     "path with --teacher.* flags. The generic BaseEnv 'process' and "
                     "'evaluate' commands do not currently wire teacher_server_configs."
                 )
+            if isinstance(teacher_server_configs, APIServerConfig):
+                teacher_config_source = [teacher_server_configs]
+            else:
                 teacher_config_source = teacher_server_configs
             self.teacher_server = ServerManager(
                 teacher_config_source,

atroposlib/tests/test_teacher_distillation_env.py

@@ -257,6 +257,49 @@ def test_init_uses_explicit_teacher_server_configs(monkeypatch):
     assert called["teacher_tokenizer_name"] == "explicit-tokenizer"
 
 
+def test_init_wraps_bare_teacher_api_server_config(monkeypatch):
+    from atroposlib.envs import teacher_distillation_env as module
+
+    called = {}
+
+    def _fake_base_init(self, config, server_configs, slurm=False, testing=False):
+        self.config = config
+        self.tokenizer = _DummyTokenizer()
+
+    def _fake_validate(self, teacher_tokenizer_name):
+        called["teacher_tokenizer_name"] = teacher_tokenizer_name
+
+    monkeypatch.setattr(module.BaseEnv, "__init__", _fake_base_init)
+    monkeypatch.setattr(module, "ServerManager", _CapturingServerManager)
+    monkeypatch.setattr(
+        _ConcreteTeacherEnv,
+        "_validate_teacher_tokenizer_compatibility",
+        _fake_validate,
+    )
+
+    explicit_cfg = APIServerConfig(
+        model_name="explicit-model",
+        tokenizer_name="explicit-tokenizer",
+        base_url="http://explicit/v1",
+        api_key="x",
+        server_type="vllm",
+    )
+    config = SimpleNamespace(
+        teacher_enabled=True,
+        teacher_top_k=0,
+    )
+
+    env = _ConcreteTeacherEnv(
+        config=config,
+        server_configs=[],
+        teacher_server_configs=explicit_cfg,
+    )
+
+    assert isinstance(env.teacher_server, _CapturingServerManager)
+    assert env.teacher_server.configs == [explicit_cfg]
+    assert called["teacher_tokenizer_name"] == "explicit-tokenizer"
+
+
 def test_resolve_teacher_server_configs_returns_none_when_unset():
     assert (
         _ConcreteTeacherEnv._resolve_teacher_server_configs(