@@ -79,7 +79,7 @@ def test_get_ops_object(ops_file_fixture, with_failure):
     assert obj.name == 'bar'
     log = wizard.console.log_text
     assert 'name of the FOOMAGIC' in log
-    fail_msg = 'Something went wrong'
+    fail_msg = 'not a valid option'
     if with_failure:
         assert fail_msg in log
     else:
 
@@ -1,12 +1,10 @@
 from paths_cli.parameters import INPUT_FILE
 from paths_cli.wizard.core import get_object
-from paths_cli.wizard.standard_categories import CATEGORIES
-from paths_cli.wizard.helper import Helper
-from functools import partial
 
 from paths_cli.wizard.errors import FILE_LOADING_ERROR_MSG
 LABEL = "Load existing from OPS file"
 
+
 def named_objs_helper(storage, store_name):
     def list_items(user_input, context=None):
         store = getattr(storage, store_name)
@@ -25,24 +23,21 @@ def _get_ops_storage(wizard):
         storage = INPUT_FILE.get(filename)
     except Exception as e:
         wizard.exception(FILE_LOADING_ERROR_MSG, e)
-        return
+        return None
 
     return storage
 
+
 @get_object
 def _get_ops_object(wizard, storage, store_name, obj_name):
-    name = wizard.ask(f"What's the name of the {obj_name} you want to "
-                      "load? (Type '?' to get a list of them)",
-                      helper=named_objs_helper(storage, store_name))
-    if name:
-        try:
-            obj = getattr(storage, store_name)[name]
-        except Exception as e:
-            wizard.exception("Something went wrong when loading "
-                   f"{name}. Maybe check the spelling?", e)
-            return
-        else:
-            return obj
+    store = getattr(storage, store_name)
+    options = {obj.name: obj for obj in store if obj.is_named}
+    result = wizard.ask_enumerate_dict(
+        f"What's the name of the {obj_name} you want to load?",
+        options
+    )
+    return result
+
 
 def load_from_ops(wizard, store_name, obj_name):
     wizard.say("Okay, we'll load it from an OPS file.")
 
@@ -61,7 +61,12 @@
             ProxyParameter(
                 name='n_frames_max',
                 ask="How many frames before aborting a trajectory?",
-                helper=None,
+                helper=("Sometimes trajectories can get stuck in "
+                        "unexpected basins. To prevent your trajectory "
+                        "from running forever, you need to add a cutoff "
+                        "trajectory length. This should be significantly "
+                        "longer than you would expect a transition to "
+                        "take."),
             ),
         ],
         compiler_plugin=OPENMM_COMPILING,
 
@@ -1,4 +1,5 @@
 import operator
+from functools import partial
 from paths_cli.wizard.parameters import ProxyParameter
 from paths_cli.wizard.plugin_classes import (
     LoadFromOPS, WizardParameterObjectPlugin, WizardObjectPlugin,
@@ -7,7 +8,7 @@
 from paths_cli.wizard.helper import EvalHelperFunc, Helper
 from paths_cli.wizard.core import interpret_req
 import paths_cli.compiling.volumes
-from functools import partial
+
 
 def _binary_func_volume(wizard, context, op):
     wizard.say("Let's make the first constituent volume:")
@@ -28,6 +29,7 @@ def _binary_func_volume(wizard, context, op):
 _LAMBDA_STR = ("What is the {minmax} allowed value for "
                "'{{obj_dict[cv].name}}' in this volume?")
 
+
 CV_DEFINED_VOLUME_PLUGIN = WizardParameterObjectPlugin.from_proxies(
     name="CV-defined volume (allowed values of CV)",
     category="volume",
@@ -57,24 +59,33 @@ def _binary_func_volume(wizard, context, op):
     compiler_plugin=paths_cli.compiling.volumes.CV_VOLUME_PLUGIN,
 )
 
+
 INTERSECTION_VOLUME_PLUGIN = WizardObjectPlugin(
     name='Intersection of two volumes (must be in both)',
     category="volume",
     intro=("This volume will be the intersection of two other volumes. "
            "This means that it only allows phase space points that are "
            "in both of the constituent volumes."),
     builder=partial(_binary_func_volume, op=operator.__and__),
+    description=("Create a volume that is the intersection of two existing "
+                 "volumes -- that is, all points in this volume are in "
+                 "both of the volumes that define it."),
 )
 
+
 UNION_VOLUME_PLUGIN = WizardObjectPlugin(
     name='Union of two volumes (must be in at least one)',
     category="volume",
     intro=("This volume will be the union of two other volumes. "
            "This means that it allows phase space points that are in "
            "either of the constituent volumes."),
     builder=partial(_binary_func_volume, op=operator.__or__),
+    description=("Create a volume that is the union of two existing "
+                 "volumes -- that is, any point in either of the volumes "
+                 "that define this are also in this volume"),
 )
 
+
 NEGATED_VOLUME_PLUGIN = WizardObjectPlugin(
     name='Complement of a volume (not in given volume)',
     category='volume',
@@ -83,15 +94,19 @@ def _binary_func_volume(wizard, context, op):
     builder=lambda wizard, context: ~VOLUMES_PLUGIN(
         wizard, volume_set_context(wizard, context, None)
     ),
+    description=("Create a volume that includes every that is NOT "
+                 "in the existing volume."),
 )
 
+
 _FIRST_STATE = ("Now  let's define state states for your system. "
                 "You'll need to define {n_states_string} of them.")
 _ADDITIONAL_STATES = "Okay, let's define another stable state."
 _VOL_DESC = ("You can describe this as either a range of values for some "
              "CV, or as some combination of other such volumes "
              "(i.e., intersection or union).")
 
+
 def volume_intro(wizard, context):
     as_state = context.get('depth', 0) == 0
     n_states = len(wizard.states)
@@ -106,24 +121,32 @@ def volume_intro(wizard, context):
     intro += [_VOL_DESC]
     return intro
 
+
 def volume_set_context(wizard, context, selected):
     depth = context.get('depth', 0) + 1
     new_context = {
         'depth': depth,
     }
     return new_context
 
+
 def volume_ask(wizard, context):
     as_state = context.get('depth', 0) == 0
     obj = {True: 'state', False: 'volume'}[as_state]
     return f"What describes this {obj}?"
 
+
+VOLUME_FROM_FILE = LoadFromOPS('volume')
+
 VOLUMES_PLUGIN = WrapCategory(
     name='volume',
     intro=volume_intro,
     ask=volume_ask,
     set_context=volume_set_context,
-    helper="No volume help yet"
+    helper=("This will define a (hyper)volume in phase space. States and "
+            "interfaces in OPS are described by volumes. You can combine "
+            "ranges along different CVs in any way you want to defined the "
+            "volume.")
 )
 
 if __name__ == "__main__":  # no-cov