diff --git a/lib/objects.py b/lib/objects.py
index caa90b42ab3b9dbb475e1a8aeaac0ca9d3993ea7..b8d67eae4fdd3a78c4b890e72b3e326aef9b0df8 100644
--- a/lib/objects.py
+++ b/lib/objects.py
@@ -291,6 +291,9 @@ class ConfigObject(object):
       slots.extend(getattr(parent, "__slots__", []))
     return slots
 
+  #: Public getter for the defined slots
+  GetAllSlots = _all_slots
+
   def ToDict(self):
     """Convert to a dict holding only standard python types.
 
diff --git a/lib/opcodes.py b/lib/opcodes.py
index d99636e1f22e0e9ec115d52837a0672e8e95d384..e266079b02d2a7c94249d3d4687841e262ca9e6c 100644
--- a/lib/opcodes.py
+++ b/lib/opcodes.py
@@ -39,6 +39,8 @@ import re
 from ganeti import constants
 from ganeti import errors
 from ganeti import ht
+from ganeti import objects
+from ganeti import query
 
 
 # Common opcode attributes
@@ -198,6 +200,13 @@ _TQueryRow = \
                      ht.TItems([ht.TElemOf(constants.RS_ALL),
                                 ht.TAny])))
 
+_TQueryResult = ht.TListOf(_TQueryRow)
+
+_TOldQueryRow = ht.TListOf(ht.TAny)
+
+_TOldQueryResult = ht.TListOf(_TOldQueryRow)
+
+
 _SUMMARY_PREFIX = {
   "CLUSTER_": "C_",
   "GROUP_": "G_",
@@ -233,6 +242,28 @@ def _NameToId(name):
   return "_".join(n.upper() for n in elems)
 
 
+def _GenerateObjectTypeCheck(obj, fields_types):
+  """Helper to generate type checks for objects.
+
+  @param obj: The object to generate type checks
+  @param fields_types: The fields and their types as a dict
+  @return: A ht type check function
+
+  """
+  assert set(obj.GetAllSlots()) == set(fields_types.keys()), \
+    "%s != %s" % (set(obj.GetAllSlots()), set(fields_types.keys()))
+  return ht.TStrictDict(True, True, fields_types)
+
+
+_TObjFdefs = \
+    _GenerateObjectTypeCheck(objects.QueryFieldDefinition, {
+      "name": ht.TRegex(query.FIELD_NAME_RE),
+      "title": ht.TRegex(query.TITLE_RE),
+      "kind": ht.TElemOf(constants.QFT_ALL),
+      "doc": ht.TRegex(query.DOC_RE),
+      })
+
+
 def RequireFileStorage():
   """Checks that file storage is enabled.
 
@@ -642,6 +673,7 @@ class OpClusterDestroy(OpCode):
 
 class OpClusterQuery(OpCode):
   """Query cluster information."""
+  OP_RESULT = ht.TDictOf(ht.TNonEmptyString, ht.TAny)
 
 
 class OpClusterVerify(OpCode):
@@ -887,6 +919,11 @@ class OpQuery(OpCode):
     ("qfilter", None, ht.TOr(ht.TNone, ht.TListOf),
      "Query filter"),
     ]
+  OP_RESULT = \
+      _GenerateObjectTypeCheck(objects.QueryResponse, {
+        "fields": ht.TListOf(_TObjFdefs),
+        "data": _TQueryResult,
+        })
 
 
 class OpQueryFields(OpCode):
@@ -902,6 +939,10 @@ class OpQueryFields(OpCode):
     ("fields", None, ht.TMaybeListOf(ht.TNonEmptyString),
      "Requested fields; if not given, all are returned"),
     ]
+  OP_RESULT = \
+      _GenerateObjectTypeCheck(objects.QueryFieldsResponse, {
+        "fields": ht.TListOf(_TObjFdefs),
+        })
 
 
 class OpOobCommand(OpCode):
@@ -919,7 +960,7 @@ class OpOobCommand(OpCode):
      "Time in seconds to wait between powering on nodes"),
     ]
   # Fixme: Make it more specific with all the special cases in LUOobCommand
-  OP_RESULT = ht.TListOf(_TQueryRow)
+  OP_RESULT = _TQueryResult
 
 
 # node opcodes
@@ -993,6 +1034,7 @@ class OpNodeQuery(OpCode):
     ("names", ht.EmptyList, ht.TListOf(ht.TNonEmptyString),
      "Empty list to query all nodes, node names otherwise"),
     ]
+  OP_RESULT = _TOldQueryResult
 
 
 class OpNodeQueryvols(OpCode):
@@ -1013,6 +1055,7 @@ class OpNodeQueryStorage(OpCode):
     ("nodes", ht.EmptyList, ht.TListOf(ht.TNonEmptyString), "List of nodes"),
     ("name", None, ht.TMaybeString, "Storage name"),
     ]
+  OP_RESULT = _TOldQueryResult
 
 
 class OpNodeModifyStorage(OpCode):
@@ -1402,6 +1445,7 @@ class OpInstanceQuery(OpCode):
     ("names", ht.EmptyList, ht.TListOf(ht.TNonEmptyString),
      "Empty list to query all instances, instance names otherwise"),
     ]
+  OP_RESULT = _TOldQueryResult
 
 
 class OpInstanceQueryData(OpCode):
@@ -1414,6 +1458,7 @@ class OpInstanceQueryData(OpCode):
      "Whether to only return configuration data without querying"
      " nodes"),
     ]
+  OP_RESULT = ht.TDictOf(ht.TNonEmptyString, ht.TDict)
 
 
 def _TestInstSetParamsModList(fn):
@@ -1546,6 +1591,7 @@ class OpGroupQuery(OpCode):
     ("names", ht.EmptyList, ht.TListOf(ht.TNonEmptyString),
      "Empty list to query all groups, group names otherwise"),
     ]
+  OP_RESULT = _TOldQueryResult
 
 
 class OpGroupSetParams(OpCode):
@@ -1602,6 +1648,7 @@ class OpOsDiagnose(OpCode):
     ("names", ht.EmptyList, ht.TListOf(ht.TNonEmptyString),
      "Which operating systems to diagnose"),
     ]
+  OP_RESULT = _TOldQueryResult
 
 
 # Exports opcodes
diff --git a/test/ganeti.opcodes_unittest.py b/test/ganeti.opcodes_unittest.py
index a31503e96cf5f7d791b10dd6f99ae5c3ed1a588d..b94ab1432f5092e7c7f5199f95df1138f7e00b59 100755
--- a/test/ganeti.opcodes_unittest.py
+++ b/test/ganeti.opcodes_unittest.py
@@ -38,15 +38,6 @@ import testutils
 #: Unless an opcode is included in the following list it must have a result
 #: check of some sort
 MISSING_RESULT_CHECK = frozenset([
-  opcodes.OpClusterQuery,
-  opcodes.OpGroupQuery,
-  opcodes.OpInstanceQuery,
-  opcodes.OpInstanceQueryData,
-  opcodes.OpNodeQuery,
-  opcodes.OpNodeQueryStorage,
-  opcodes.OpOsDiagnose,
-  opcodes.OpQuery,
-  opcodes.OpQueryFields,
   opcodes.OpTagsDel,
   opcodes.OpTagsGet,
   opcodes.OpTagsSearch,