diff --git a/.gitignore b/.gitignore
index 98acab5..e63e24b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -111,7 +111,7 @@ celerybeat.pid
 .env
 .venv
 venv/
-ENV/
+/ENV/
 env.bak/
 venv.bak/
 
diff --git a/pyproject.toml b/pyproject.toml
index aa66eb5..c47b14b 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -143,8 +143,8 @@ line-length = 100
 target-version = ["py311"]
 
 [tool.nbqa.exclude]
-ruff = ".jupyter_cache"
-mypy = ".jupyter_cache"
+ruff = "\\.jupyter_cache|jupyter_execute"
+mypy = "\\.jupyter_cache|jupyter_execute"
 
 [tool.ruff]
 select = [
@@ -203,10 +203,10 @@ test = "pytest test --cov=tianshou --cov-report=xml --cov-report=term-missing --
 test-reduced = "pytest test/base test/continuous --cov=tianshou --durations=0 -v --color=yes"
 _black_check = "black --check ."
 _ruff_check = "ruff check ."
-_ruff_check_nb = "nbqa ruff ."
+_ruff_check_nb = "nbqa ruff docs"
 _black_format = "black ."
 _ruff_format = "ruff --fix ."
-_ruff_format_nb = "nbqa ruff --fix ."
+_ruff_format_nb = "nbqa ruff --fix docs"
 lint = ["_black_check", "_ruff_check", "_ruff_check_nb"]
 _poetry_install_sort_plugin = "poetry self add poetry-plugin-sort"
 _poetry_sort = "poetry sort"
@@ -221,5 +221,5 @@ doc-generate-files = ["_autogen_rst", "_jb_generate_toc", "_jb_generate_config"]
 doc-spellcheck = "sphinx-build -W -b spelling docs docs/_build"
 doc-build = ["doc-generate-files", "doc-spellcheck", "_sphinx_build"]
 _mypy = "mypy tianshou"
-_mypy_nb = "nbqa mypy ."
+_mypy_nb = "nbqa mypy docs"
 type-check = ["_mypy", "_mypy_nb"]
diff --git a/tianshou/env/worker/ray.py b/tianshou/env/worker/ray.py
index f465eae..76b8422 100644
--- a/tianshou/env/worker/ray.py
+++ b/tianshou/env/worker/ray.py
@@ -12,6 +12,9 @@ with contextlib.suppress(ImportError):
     import ray
 
 
+# mypy: disable-error-code="unused-ignore"
+
+
 class _SetAttrWrapper(gym.Wrapper):
     def set_env_attr(self, key: str, value: Any) -> None:
         setattr(self.env.unwrapped, key, value)
diff --git a/tianshou/env/worker/subproc.py b/tianshou/env/worker/subproc.py
index 2ca60c2..af5ec4e 100644
--- a/tianshou/env/worker/subproc.py
+++ b/tianshou/env/worker/subproc.py
@@ -12,6 +12,9 @@ import numpy as np
 from tianshou.env.utils import CloudpickleWrapper, gym_new_venv_step_type
 from tianshou.env.worker import EnvWorker
 
+# mypy: disable-error-code="unused-ignore"
+
+
 _NP_TO_CT = {
     np.bool_: ctypes.c_bool,
     np.uint8: ctypes.c_uint8,
@@ -179,10 +182,10 @@ class SubprocEnvWorker(EnvWorker):
                 if remain_time <= 0:
                     break
             # connection.wait hangs if the list is empty
-            new_ready_conns = connection.wait(remain_conns, timeout=remain_time)
+            new_ready_conns = connection.wait(remain_conns, timeout=remain_time)  # type: ignore
             ready_conns.extend(new_ready_conns)  # type: ignore
-            remain_conns = [conn for conn in remain_conns if conn not in ready_conns]
-        return [workers[conns.index(con)] for con in ready_conns]
+            remain_conns = [conn for conn in remain_conns if conn not in ready_conns]  # type: ignore
+        return [workers[conns.index(con)] for con in ready_conns]  # type: ignore
 
     def send(self, action: np.ndarray | None, **kwargs: Any) -> None:
         if action is None:
diff --git a/tianshou/highlevel/agent.py b/tianshou/highlevel/agent.py
index b72ab5e..1a1a0bf 100644
--- a/tianshou/highlevel/agent.py
+++ b/tianshou/highlevel/agent.py
@@ -184,7 +184,7 @@ class OnPolicyAgentFactory(AgentFactory, ABC):
             max_epoch=sampling_config.num_epochs,
             step_per_epoch=sampling_config.step_per_epoch,
             repeat_per_collect=sampling_config.repeat_per_collect,
-            episode_per_test=sampling_config.num_test_envs,
+            episode_per_test=sampling_config.num_test_episodes_per_test_env,
             batch_size=sampling_config.batch_size,
             step_per_collect=sampling_config.step_per_collect,
             save_best_fn=policy_persistence.get_save_best_fn(world),
@@ -228,7 +228,7 @@ class OffPolicyAgentFactory(AgentFactory, ABC):
             max_epoch=sampling_config.num_epochs,
             step_per_epoch=sampling_config.step_per_epoch,
             step_per_collect=sampling_config.step_per_collect,
-            episode_per_test=sampling_config.num_test_envs,
+            episode_per_test=sampling_config.num_test_episodes_per_test_env,
             batch_size=sampling_config.batch_size,
             save_best_fn=policy_persistence.get_save_best_fn(world),
             logger=world.logger,
diff --git a/tianshou/highlevel/config.py b/tianshou/highlevel/config.py
index 80e0476..4982472 100644
--- a/tianshou/highlevel/config.py
+++ b/tianshou/highlevel/config.py
@@ -1,3 +1,4 @@
+import math
 import multiprocessing
 from dataclasses import dataclass
 
@@ -16,7 +17,10 @@ class SamplingConfig(ToStringMixin):
 
       * collects environment steps/transitions (collection step), adding them to the (replay)
         buffer (see :attr:`step_per_collect`)
-      * performs one or more gradient updates (see :attr:`update_per_step`).
+      * performs one or more gradient updates (see :attr:`update_per_step`),
+
+    and the test step collects :attr:`num_episodes_per_test` test episodes in order to evaluate
+    agent performance.
 
     The number of training steps in each epoch is indirectly determined by
     :attr:`step_per_epoch`: As many training steps will be performed as are required in
@@ -49,6 +53,12 @@ class SamplingConfig(ToStringMixin):
     num_test_envs: int = 1
     """the number of test environments to use"""
 
+    num_test_episodes: int = 1
+    """the total number of episodes to collect in each test step (across all test environments).
+    This should be a multiple of the number of test environments; if it is not, the effective
+    number of episodes collected will be the nearest multiple (rounded up).
+    """
+
     buffer_size: int = 4096
     """the total size of the sample/replay buffer, in which environment steps (transitions) are
     stored"""
@@ -119,3 +129,8 @@ class SamplingConfig(ToStringMixin):
     def __post_init__(self) -> None:
         if self.num_train_envs == -1:
             self.num_train_envs = multiprocessing.cpu_count()
+
+    @property
+    def num_test_episodes_per_test_env(self) -> int:
+        """:return: the number of episodes to collect per test environment in every test step"""
+        return math.ceil(self.num_test_episodes / self.num_test_envs)
diff --git a/tianshou/highlevel/optim.py b/tianshou/highlevel/optim.py
index 0e754b1..db5fd90 100644
--- a/tianshou/highlevel/optim.py
+++ b/tianshou/highlevel/optim.py
@@ -1,11 +1,14 @@
 from abc import ABC, abstractmethod
-from typing import Any, Protocol
+from collections.abc import Iterable
+from typing import Any, Protocol, TypeAlias
 
 import torch
 from torch.optim import Adam, RMSprop
 
 from tianshou.utils.string import ToStringMixin
 
+TParams: TypeAlias = Iterable[torch.Tensor] | Iterable[dict[str, Any]]
+
 
 class OptimizerWithLearningRateProtocol(Protocol):
     def __call__(self, parameters: Any, lr: float, **kwargs: Any) -> torch.optim.Optimizer:
@@ -13,8 +16,15 @@ class OptimizerWithLearningRateProtocol(Protocol):
 
 
 class OptimizerFactory(ABC, ToStringMixin):
+    def create_optimizer(
+        self,
+        module: torch.nn.Module,
+        lr: float,
+    ) -> torch.optim.Optimizer:
+        return self.create_optimizer_for_params(module.parameters(), lr)
+
     @abstractmethod
-    def create_optimizer(self, module: torch.nn.Module, lr: float) -> torch.optim.Optimizer:
+    def create_optimizer_for_params(self, params: TParams, lr: float) -> torch.optim.Optimizer:
         pass
 
 
@@ -30,8 +40,8 @@ class OptimizerFactoryTorch(OptimizerFactory):
         self.optim_class = optim_class
         self.kwargs = kwargs
 
-    def create_optimizer(self, module: torch.nn.Module, lr: float) -> torch.optim.Optimizer:
-        return self.optim_class(module.parameters(), lr=lr, **self.kwargs)
+    def create_optimizer_for_params(self, params: TParams, lr: float) -> torch.optim.Optimizer:
+        return self.optim_class(params, lr=lr, **self.kwargs)
 
 
 class OptimizerFactoryAdam(OptimizerFactory):
@@ -45,9 +55,9 @@ class OptimizerFactoryAdam(OptimizerFactory):
         self.eps = eps
         self.betas = betas
 
-    def create_optimizer(self, module: torch.nn.Module, lr: float) -> Adam:
+    def create_optimizer_for_params(self, params: TParams, lr: float) -> torch.optim.Optimizer:
         return Adam(
-            module.parameters(),
+            params,
             lr=lr,
             betas=self.betas,
             eps=self.eps,
@@ -70,9 +80,9 @@ class OptimizerFactoryRMSprop(OptimizerFactory):
         self.weight_decay = weight_decay
         self.eps = eps
 
-    def create_optimizer(self, module: torch.nn.Module, lr: float) -> RMSprop:
+    def create_optimizer_for_params(self, params: TParams, lr: float) -> torch.optim.Optimizer:
         return RMSprop(
-            module.parameters(),
+            params,
             lr=lr,
             alpha=self.alpha,
             eps=self.eps,
diff --git a/tianshou/highlevel/params/alpha.py b/tianshou/highlevel/params/alpha.py
index 878ae4b..4e8490d 100644
--- a/tianshou/highlevel/params/alpha.py
+++ b/tianshou/highlevel/params/alpha.py
@@ -20,7 +20,7 @@ class AutoAlphaFactory(ToStringMixin, ABC):
         pass
 
 
-class AutoAlphaFactoryDefault(AutoAlphaFactory):  # TODO better name?
+class AutoAlphaFactoryDefault(AutoAlphaFactory):
     def __init__(self, lr: float = 3e-4):
         self.lr = lr
 
@@ -32,5 +32,5 @@ class AutoAlphaFactoryDefault(AutoAlphaFactory):  # TODO better name?
     ) -> tuple[float, torch.Tensor, torch.optim.Optimizer]:
         target_entropy = float(-np.prod(envs.get_action_shape()))
         log_alpha = torch.zeros(1, requires_grad=True, device=device)
-        alpha_optim = torch.optim.Adam([log_alpha], lr=self.lr)
+        alpha_optim = optim_factory.create_optimizer_for_params([log_alpha], self.lr)
         return target_entropy, log_alpha, alpha_optim