diff --git a/src/reader/_storage.py b/src/reader/_storage.py
index afb7f9c5..7669dc19 100644
--- a/src/reader/_storage.py
+++ b/src/reader/_storage.py
@@ -5,7 +5,6 @@
 from datetime import timedelta
 from functools import partial
 from typing import Any
-from typing import cast
 from typing import Dict
 from typing import Iterable
 from typing import Mapping
@@ -984,7 +983,7 @@ def _add_or_update_entries(
 
             except sqlite3.IntegrityError as e:
                 e_msg = str(e).lower()
-                feed_url, entry_id = intent.entry.object_id
+                feed_url, entry_id = intent.entry.resource_id
 
                 log.debug(
                     "add_entry %r of feed %r: got IntegrityError",
@@ -1269,7 +1268,7 @@ def delete_tag(self, object_id: ResourceId, key: str) -> None:
 
         with self.get_db() as db:
             cursor = db.execute(query, params)
-        rowcount_exactly_one(cursor, lambda: TagNotFoundError(key, cast(str, None)))
+        rowcount_exactly_one(cursor, lambda: TagNotFoundError(key, object_id))
 
 
 def make_get_feeds_query(
diff --git a/src/reader/_types.py b/src/reader/_types.py
index a0d9277d..0e53b34e 100644
--- a/src/reader/_types.py
+++ b/src/reader/_types.py
@@ -16,6 +16,7 @@
 from typing import Union
 
 from ._hash_utils import get_hash
+from ._utils import deprecated
 from .types import _entry_argument
 from .types import _feed_argument
 from .types import _namedtuple_compat
@@ -64,7 +65,12 @@ def as_feed(self, **kwargs: object) -> Feed:
         return Feed(**attrs)
 
     @property
-    def object_id(self) -> str:
+    def resource_id(self) -> Tuple[str]:
+        return (self.url,)
+
+    @property  # type: ignore
+    @deprecated('resource_id', '2.17', '3.0', property=True)
+    def object_id(self) -> str:  # pragma: no cover
         return self.url
 
     _hash_exclude_ = frozenset({'url', 'updated'})
@@ -121,7 +127,12 @@ def as_entry(self, **kwargs: object) -> Entry:
         return Entry(**attrs)
 
     @property
-    def object_id(self) -> Tuple[str, str]:
+    def resource_id(self) -> Tuple[str, str]:
+        return self.feed_url, self.id
+
+    @property  # type: ignore
+    @deprecated('resource_id', '2.17', '3.0', property=True)
+    def object_id(self) -> Tuple[str, str]:  # pragma: no cover
         return self.feed_url, self.id
 
     _hash_exclude_ = frozenset({'feed_url', 'id', 'updated'})
diff --git a/src/reader/_utils.py b/src/reader/_utils.py
index b1448dd8..af4d46b4 100644
--- a/src/reader/_utils.py
+++ b/src/reader/_utils.py
@@ -20,9 +20,6 @@
 from typing import TypeVar
 from typing import Union
 
-from .types import MISSING
-from .types import MissingType
-
 
 FuncType = Callable[..., Any]
 F = TypeVar('F', bound=FuncType)
@@ -31,6 +28,15 @@
 _U = TypeVar('_U')
 
 
+class MissingType:
+    def __repr__(self) -> str:
+        return "no value"
+
+
+#: Sentinel object used to detect if the `default` argument was provided."""
+MISSING = MissingType()
+
+
 def zero_or_one(
     it: Iterable[_U],
     make_exc: Callable[[], Exception],
@@ -197,6 +203,33 @@ def process(self, msg: str, kwargs: Any) -> Tuple[str, Any]:  # pragma: no cover
         return ': '.join(tuple(self._escape(p) for p in self.prefixes) + (msg,)), kwargs
 
 
+_DEPRECATED_FUNC_WARNING = """\
+{old_name}() is deprecated and will be removed in reader {removed_in}. \
+Use {new_name}() instead.\
+"""
+_DEPRECATED_FUNC_DOCSTRING = """\
+Deprecated alias for :meth:`{new_name}`.
+{doc}
+.. deprecated:: {deprecated_in}
+    This method will be removed in *reader* {removed_in}.
+    Use :meth:`{new_name}` instead.
+
+"""
+
+_DEPRECATED_PROP_WARNING = """\
+{old_name} is deprecated and will be removed in reader {removed_in}. \
+Use {new_name} instead.\
+"""
+_DEPRECATED_PROP_DOCSTRING = """\
+Deprecated variant of :attr:`{new_name}`.
+{doc}
+.. deprecated:: {deprecated_in}
+    This property will be removed in *reader* {removed_in}.
+    Use :attr:`{new_name}` instead.
+
+"""
+
+
 def _deprecated_wrapper(
     old_name: str,
     new_name: str,
@@ -204,26 +237,18 @@ def _deprecated_wrapper(
     deprecated_in: str,
     removed_in: str,
     doc: str = '',
+    warning_template: str = _DEPRECATED_FUNC_WARNING,
+    docstring_template: str = _DEPRECATED_FUNC_DOCSTRING,
 ) -> F:
+    format_kwargs = dict(locals())
+
     @wraps(func)
     def old_func(*args, **kwargs):  # type: ignore
-        warnings.warn(
-            f"{old_name}() is deprecated "
-            f"and will be removed in reader {removed_in}. "
-            f"Use {new_name}() instead.",
-            DeprecationWarning,
-        )
+        warnings.warn(warning_template.format_map(format_kwargs), DeprecationWarning)
         return func(*args, **kwargs)
 
     old_func.__name__ = old_name
-    old_func.__doc__ = (
-        f"Deprecated alias for :meth:`{new_name}`.\n"
-        f"{doc}\n"
-        f".. deprecated:: {deprecated_in}\n"
-        f"    This method will be removed in *reader* {removed_in}.\n"
-        f"    Use :meth:`{new_name}` instead.\n\n"
-    )
-
+    old_func.__doc__ = docstring_template.format_map(format_kwargs)
     return cast(F, old_func)
 
 
@@ -233,18 +258,23 @@ def deprecated_wrapper(
     return _deprecated_wrapper(old_name, func.__name__, func, deprecated_in, removed_in)
 
 
-def deprecated(new_name: str, deprecated_in: str, removed_in: str) -> Callable[[F], F]:
+def deprecated(
+    new_name: str, deprecated_in: str, removed_in: str, property: bool = False
+) -> Callable[[F], F]:
+    if not property:
+        kwargs = {}
+    else:
+        kwargs = dict(
+            warning_template=_DEPRECATED_PROP_WARNING,
+            docstring_template=_DEPRECATED_PROP_DOCSTRING,
+        )
+
     def decorator(func: F) -> F:
         doc = inspect.getdoc(func) or ''
         if doc:  # pragma: no cover
             doc = '\n' + doc + '\n'
         return _deprecated_wrapper(
-            func.__name__,
-            new_name,
-            func,
-            deprecated_in,
-            removed_in,
-            doc=doc,
+            func.__name__, new_name, func, deprecated_in, removed_in, doc=doc, **kwargs
         )
 
     return decorator
diff --git a/src/reader/core.py b/src/reader/core.py
index f35cc261..a404d6d4 100644
--- a/src/reader/core.py
+++ b/src/reader/core.py
@@ -363,7 +363,7 @@ def __init__(
         #:
         #:  The only `entry` attributes guaranteed to be present are
         #:  :attr:`~Entry.feed_url`, :attr:`~Entry.id`,
-        #:  and :attr:`~Entry.object_id`;
+        #:  and :attr:`~Entry.resource_id`;
         #:  all other attributes may be missing
         #:  (accessing them may raise :exc:`AttributeError`).
         #:
@@ -2054,10 +2054,9 @@ def get_tag(
 
         """
         resource_id = _resource_argument(resource)
-        object_id: Any = resource_id if len(resource_id) != 1 else resource_id[0]  # type: ignore
         return zero_or_one(
             (v for _, v in self._storage.get_tags(resource_id, key)),
-            lambda: TagNotFoundError(key, object_id),
+            lambda: TagNotFoundError(key, resource_id),
             default,
         )
 
@@ -2131,12 +2130,10 @@ def delete_tag(
 
         """
         resource_id = _resource_argument(resource)
-        object_id: Any = resource_id if len(resource_id) != 1 else resource_id[0]  # type: ignore
         try:
             self._storage.delete_tag(resource_id, key)
-        except TagNotFoundError as e:
+        except TagNotFoundError:
             if not missing_ok:
-                e.object_id = object_id
                 raise
 
     def make_reader_reserved_name(self, key: str) -> str:
diff --git a/src/reader/exceptions.py b/src/reader/exceptions.py
index b654f0aa..54be46be 100644
--- a/src/reader/exceptions.py
+++ b/src/reader/exceptions.py
@@ -3,6 +3,8 @@
 from typing import Tuple
 from typing import Union
 
+from ._utils import deprecated
+
 
 class _FancyExceptionBase(Exception):
 
@@ -72,7 +74,10 @@ class ResourceNotFoundError(ReaderError):
 
     """
 
-    # TODO: object_id: tuple[str, ...] (but FeedError must become tuple[str]!)
+    @property
+    def resource_id(self) -> Tuple[str, ...]:  # pragma: no cover
+        """The `resource_id` of the resource."""
+        raise NotImplementedError
 
 
 class FeedError(ReaderError):
@@ -89,7 +94,17 @@ def _str(self) -> str:
         return repr(self.url)
 
     @property
-    def object_id(self) -> str:
+    def resource_id(self) -> Tuple[str]:
+        """Alias for (:attr:`~url`,).
+
+        .. versionadded:: 2.17
+
+        """
+        return (self.url,)
+
+    @property  # type: ignore
+    @deprecated('resource_id', '2.17', '3.0', property=True)
+    def object_id(self) -> str:  # pragma: no cover
         """Alias for :attr:`~FeedError.url`.
 
         .. versionadded:: 1.12
@@ -149,7 +164,17 @@ def _str(self) -> str:
         return repr((self.feed_url, self.id))
 
     @property
-    def object_id(self) -> Tuple[str, str]:
+    def resource_id(self) -> Tuple[str, str]:
+        """Alias for (:attr:`~feed_url`, :attr:`~id`).
+
+        .. versionadded:: 2.17
+
+        """
+        return self.feed_url, self.id
+
+    @property  # type: ignore
+    @deprecated('resource_id', '2.17', '3.0', property=True)
+    def object_id(self) -> Tuple[str, str]:  # pragma: no cover
         """Alias for (:attr:`~EntryError.feed_url`, :attr:`~EntryError.id`).
 
         .. versionadded:: 1.12
@@ -286,27 +311,39 @@ class TagError(ReaderError):
 
     .. versionadded:: 2.8
 
+    .. versionchanged:: 2.17
+        Signature changed from ``TagError(key, object_id, message='')``
+        to ``TagError(key, resource_id, message='')``.
+
     """
 
     def __init__(
-        self,
-        key: str,
-        object_id: Union[Tuple[()], str, Tuple[str, str]],
-        message: str = '',
+        self, key: str, resource_id: Tuple[str, ...], message: str = ''
     ) -> None:
         super().__init__(message)
 
         #: The tag key.
         self.key = key
 
-        # TODO: tuple[str, ...], once FeedError.object_id becomes tuple[str]
-
-        #: The `object_id` of the resource.
-        self.object_id = object_id
+        #: The `resource_id` of the resource.
+        self.resource_id = resource_id
 
     @property
     def _str(self) -> str:
-        return f"{self.object_id!r}: {self.key!r}"
+        parts = self.resource_id + (self.key,)
+        return ': '.join(repr(part) for part in parts)
+
+    @property  # type: ignore
+    @deprecated('resource_id', '2.17', '3.0', property=True)
+    def object_id(self) -> Union[Tuple[()], str, Tuple[str, str]]:  # pragma: no cover
+        """The `object_id` of the resource."""
+        if len(self.resource_id) == 0:
+            return ()
+        if len(self.resource_id) == 1:
+            return self.resource_id[0]
+        if len(self.resource_id) == 2:
+            return self.resource_id[0], self.resource_id[1]
+        assert False, "shouldn't happen"  # noqa: B011
 
 
 class TagNotFoundError(TagError):
diff --git a/src/reader/plugins/entry_dedupe.py b/src/reader/plugins/entry_dedupe.py
index 996026e5..c63036e5 100644
--- a/src/reader/plugins/entry_dedupe.py
+++ b/src/reader/plugins/entry_dedupe.py
@@ -270,7 +270,7 @@ def _get_same_group_entries(reader, entry):
     # https://github.com/lemon24/reader/issues/202
 
     for other in reader.get_entries(feed=entry.feed_url, read=None):
-        if entry.object_id == other.object_id:
+        if entry.resource_id == other.resource_id:
             continue
         if _normalize(entry.title) != _normalize(other.title):
             continue
@@ -320,7 +320,7 @@ def by_title(e):
         return _normalize(e.title)
 
     # this reads all the feed's entries in memory;
-    # better would be to get all the (e.title, e.object_id),
+    # better would be to get all the (e.title, e.resource_id),
     # sort them, and then get_entry() each entry in order;
     # even better would be to have get_entries(sort='title');
     # https://github.com/lemon24/reader/issues/202
@@ -455,7 +455,7 @@ def _get_tags(reader, entry, duplicates):
             else:  # pragma: no cover
                 # TODO: custom exception
                 raise RuntimeError(
-                    f"could not find key for entry {entry.object_id} and tag {key}"
+                    f"could not find key for entry {entry.resource_id} and tag {key}"
                 )
 
 
@@ -471,14 +471,14 @@ def _make_actions(reader, entry, duplicates):
     for key, value in _get_tags(reader, entry, duplicates):
         yield partial(reader.set_tag, entry, key, value)
 
-    duplicate_ids = [d.object_id for d in duplicates]
+    duplicate_ids = [d.resource_id for d in duplicates]
     yield partial(reader._storage.delete_entries, duplicate_ids)
 
 
 def _dedupe_entries(reader, entry, duplicates, *, dry_run):
     log.info(
         "entry_dedupe: %r (title: %r) duplicates: %r",
-        entry.object_id,
+        entry.resource_id,
         entry.title,
         [e.id for e in duplicates],
     )
diff --git a/src/reader/types.py b/src/reader/types.py
index 090210d1..a2e371d5 100644
--- a/src/reader/types.py
+++ b/src/reader/types.py
@@ -24,8 +24,14 @@
 from typing import TypeVar
 from typing import Union
 
+from reader._utils import deprecated
 from reader.exceptions import ReaderError
 
+# noreorder
+# can't be defined here because of circular imports
+from reader._utils import MISSING as MISSING  # noqa: F401
+from reader._utils import MissingType as MissingType  # noqa: F401
+
 
 _T = TypeVar('_T')
 
@@ -144,7 +150,17 @@ class Feed(_namedtuple_compat):
     updates_enabled: bool = True
 
     @property
-    def object_id(self) -> str:
+    def resource_id(self) -> Tuple[str]:
+        """Alias for (:attr:`~url`,).
+
+        .. versionadded:: 2.17
+
+        """
+        return (self.url,)
+
+    @property  # type: ignore
+    @deprecated('resource_id', '2.17', '3.0', property=True)
+    def object_id(self) -> str:  # pragma: no cover
         """Alias for :attr:`~Feed.url`.
 
         .. versionadded:: 1.12
@@ -308,7 +324,17 @@ def feed_url(self) -> str:
     feed: Feed = cast(Feed, None)
 
     @property
-    def object_id(self) -> Tuple[str, str]:
+    def resource_id(self) -> Tuple[str, str]:
+        """Alias for (:attr:`~feed_url`, :attr:`~id`).
+
+        .. versionadded:: 2.17
+
+        """
+        return self.feed_url, self.id
+
+    @property  # type: ignore
+    @deprecated('resource_id', '2.17', '3.0', property=True)
+    def object_id(self) -> Tuple[str, str]:  # pragma: no cover
         """Alias for (:attr:`~Entry.feed_url`, :attr:`~Entry.id`).
 
         .. versionadded:: 1.12
@@ -611,7 +637,17 @@ class EntrySearchResult(_namedtuple_compat):
     # TODO: entry: Optional[Entry]; model it through typing if possible
 
     @property
-    def object_id(self) -> Tuple[str, str]:
+    def resource_id(self) -> Tuple[str, str]:
+        """Alias for (:attr:`~feed_url`, :attr:`~id`).
+
+        .. versionadded:: 2.17
+
+        """
+        return self.feed_url, self.id
+
+    @property  # type: ignore
+    @deprecated('resource_id', '2.17', '3.0', property=True)
+    def object_id(self) -> Tuple[str, str]:  # pragma: no cover
         """Alias for (:attr:`~EntrySearchResult.feed_url`, :attr:`~EntrySearchResult.id`).
 
         .. versionadded:: 1.12
@@ -762,15 +798,6 @@ def _resource_argument(resource: ResourceInput) -> ResourceId:
 ]
 
 
-class MissingType:
-    def __repr__(self) -> str:
-        return "no value"
-
-
-#: Sentinel object used to detect if the `default` argument was provided."""
-MISSING = MissingType()
-
-
 @dataclass(frozen=True)
 class FeedCounts(_namedtuple_compat):
 
diff --git a/tests/test_exceptions.py b/tests/test_exceptions.py
index 03f435c3..d3883056 100644
--- a/tests/test_exceptions.py
+++ b/tests/test_exceptions.py
@@ -85,5 +85,5 @@ def test_metadata_error_str(exc_type):
 
 @pytest.mark.parametrize('exc_type', all_classes(TagError))
 def test_tag_error_str(exc_type):
-    exc = exc_type('key', 'object')
+    exc = exc_type('key', ('object',))
     assert "'object': 'key'" in str(exc)
diff --git a/tests/test_reader.py b/tests/test_reader.py
index 5f17db3f..19010d2e 100644
--- a/tests/test_reader.py
+++ b/tests/test_reader.py
@@ -2996,7 +2996,7 @@ def test_pagination_basic(reader, pre_stuff, call_method, sort_kwargs, chunk_siz
     pre_stuff(reader)
 
     def get_ids(**kwargs):
-        return [o.object_id for o in call_method(reader, **sort_kwargs, **kwargs)]
+        return [o.resource_id for o in call_method(reader, **sort_kwargs, **kwargs)]
 
     ids = get_ids()
 
@@ -3030,9 +3030,9 @@ def test_pagination_random(reader, pre_stuff, call_method, chunk_size):
     pre_stuff(reader)
 
     def get_ids(**kwargs):
-        return [o.object_id for o in call_method(reader, sort='random', **kwargs)]
+        return [o.resource_id for o in call_method(reader, sort='random', **kwargs)]
 
-    ids = [o.object_id for o in call_method(reader)]
+    ids = [o.resource_id for o in call_method(reader)]
 
     assert len(get_ids(limit=1)) == min(1, chunk_size or 1, len(ids))
     assert len(get_ids(limit=2)) == min(2, chunk_size or 2, len(ids))
@@ -3052,7 +3052,7 @@ def get_ids(**kwargs):
 }
 
 NOT_FOUND_STARTING_AFTER = {
-    get_feeds: '0',
+    get_feeds: ('0',),
     get_entries: ('1', '1, 0'),
     search_entries: ('1', '1, 0'),
 }
@@ -3067,7 +3067,7 @@ def test_starting_after_errors(reader, pre_stuff, call_method, sort_kwargs):
 
     with pytest.raises(error_cls) as excinfo:
         list(call_method(reader, **sort_kwargs, starting_after=starting_after))
-    assert excinfo.value.object_id == starting_after
+    assert excinfo.value.resource_id == starting_after
 
 
 @with_call_paginated_method
@@ -3075,7 +3075,7 @@ def test_limit_errors(reader, pre_stuff, call_method, sort_kwargs):
     pre_stuff(reader)
 
     def get_ids(**kwargs):
-        return [o.object_id for o in call_method(reader, **sort_kwargs, **kwargs)]
+        return [o.resource_id for o in call_method(reader, **sort_kwargs, **kwargs)]
 
     with pytest.raises(ValueError):
         get_ids(limit=object())
@@ -3299,7 +3299,7 @@ def test_add_entry(reader):
 
     with pytest.raises(FeedNotFoundError) as excinfo:
         reader.add_entry(dict(feed_url='1', id='1, 1'))
-    assert excinfo.value.object_id == '1'
+    assert excinfo.value.resource_id == ('1',)
 
     # add it by user (from dict)
 
@@ -3322,7 +3322,7 @@ def test_add_entry(reader):
 
     with pytest.raises(EntryExistsError) as excinfo:
         reader.add_entry(expected_entry)
-    assert excinfo.value.object_id == ('1', '1, 1')
+    assert excinfo.value.resource_id == ('1', '1, 1')
 
     # add it by user (from object)
 
@@ -3358,7 +3358,7 @@ def test_delete_entry(reader):
 
     with pytest.raises(EntryNotFoundError) as excinfo:
         reader.delete_entry(('1', '1, 1'))
-    assert excinfo.value.object_id == ('1', '1, 1')
+    assert excinfo.value.resource_id == ('1', '1, 1')
 
     # no exception
     reader.delete_entry(('1', '1, 1'), True)
@@ -3379,7 +3379,7 @@ def test_delete_entry(reader):
 
     with pytest.raises(EntryError) as excinfo:
         reader.delete_entry(('1', '1, 2'))
-    assert excinfo.value.object_id == ('1', '1, 2')
+    assert excinfo.value.resource_id == ('1', '1, 2')
     assert excinfo.value.message == "entry must be added by 'user', got 'feed'"
 
     assert {(e.id, e.added_by) for e in reader.get_entries()} == {
diff --git a/tests/test_reader_private.py b/tests/test_reader_private.py
index 4957a3f1..f3ff2bf5 100644
--- a/tests/test_reader_private.py
+++ b/tests/test_reader_private.py
@@ -128,8 +128,8 @@ def get_entry_ids():
         return [e.id for e in reader.get_entries()]
 
     with pytest.raises(EntryNotFoundError) as excinfo:
-        reader._storage.delete_entries([entry.object_id])
-    assert (excinfo.value.feed_url, excinfo.value.id) == entry.object_id
+        reader._storage.delete_entries([entry.resource_id])
+    assert (excinfo.value.feed_url, excinfo.value.id) == entry.resource_id
     assert 'no such entry' in excinfo.value.message
 
     assert get_entry_ids() == []
@@ -137,11 +137,11 @@ def get_entry_ids():
     reader.update_feeds()
     assert get_entry_ids() == ['1, 1']
 
-    reader._storage.delete_entries([entry.object_id])
+    reader._storage.delete_entries([entry.resource_id])
     assert get_entry_ids() == []
 
     with pytest.raises(EntryNotFoundError) as excinfo:
-        reader._storage.delete_entries([entry.object_id])
+        reader._storage.delete_entries([entry.resource_id])
 
     del parser.entries[1][1]
     reader.update_feeds()
diff --git a/tests/test_reader_search.py b/tests/test_reader_search.py
index ba641774..43456c7a 100644
--- a/tests/test_reader_search.py
+++ b/tests/test_reader_search.py
@@ -1091,11 +1091,11 @@ def test_add_entry_basic(reader):
     reader.update_search()
 
     (result,) = reader.search_entries('entry')
-    assert result.object_id == ('1', '1')
+    assert result.resource_id == ('1', '1')
     assert result.metadata['.title'].apply('*', '*') == 'my *entry*'
     assert result.content['.summary'].apply('*', '*') == 'I am a summary'
 
     (result,) = reader.search_entries('summary')
-    assert result.object_id == ('1', '1')
+    assert result.resource_id == ('1', '1')
     assert result.metadata['.title'].apply('*', '*') == 'my entry'
     assert result.content['.summary'].apply('*', '*') == 'I am a *summary*'
diff --git a/tests/test_tags.py b/tests/test_tags.py
index 7894e34e..ec49f89e 100644
--- a/tests/test_tags.py
+++ b/tests/test_tags.py
@@ -13,10 +13,12 @@
 
 
 @contextmanager
-def raises_TagNotFoundError(object_id, key):
+def raises_TagNotFoundError(resource_id, key):
+    if isinstance(resource_id, str):
+        resource_id = (resource_id,)
     with pytest.raises(TagNotFoundError) as excinfo:
         yield
-    assert excinfo.value.object_id == object_id
+    assert excinfo.value.resource_id == resource_id
     assert excinfo.value.key == key
     assert 'no such tag' in excinfo.value.message
 
@@ -24,7 +26,7 @@ def raises_TagNotFoundError(object_id, key):
 @parametrize_dict(
     'resource, not_found_exc',
     {
-        'feed': ('1', FeedNotFoundError),
+        'feed': (('1',), FeedNotFoundError),
         'entry': (('1', '1, 1'), EntryNotFoundError),
         # no global, the global namespace always exists
     },
@@ -41,7 +43,7 @@ def test_inexistent_resource(reader, subtests, resource, not_found_exc):
     with subtests.test("set tag"):
         with pytest.raises(not_found_exc) as excinfo:
             reader.set_tag(resource, 'one', 'value')
-        assert excinfo.value.object_id == resource
+        assert excinfo.value.resource_id == resource
         assert 'no such' in excinfo.value.message
         assert 'no such tag' not in excinfo.value.message
 
@@ -329,10 +331,10 @@ def test_set_no_value(reader, resource, value):
     {
         'global': lambda *_: (),
         'feed': lambda f, _: f,
-        'feed_id': lambda f, _: f.object_id,
+        'feed_id': lambda f, _: f.resource_id,
         'feed_tuple': lambda f, _: (f.url,),
         'entry': lambda _, e: e,
-        'entry_id': lambda _, e: e.object_id,
+        'entry_id': lambda _, e: e.resource_id,
     },
 )
 def test_resource_argument(reader, make_resource_arg):
diff --git a/tests/test_types.py b/tests/test_types.py
index 55941da8..c7c3c6cc 100644
--- a/tests/test_types.py
+++ b/tests/test_types.py
@@ -105,14 +105,14 @@ def test__resource_argument_valueerror(resource):
         _resource_argument(resource)
 
 
-def test_object_id():
-    assert Feed('url').object_id == 'url'
-    assert Entry('entry', 'updated', feed=Feed('url')).object_id == ('url', 'entry')
-    assert EntrySearchResult('url', 'entry').object_id == ('url', 'entry')
-    assert FeedData('url').object_id == 'url'
-    assert EntryData('url', 'entry', 'updated').object_id == ('url', 'entry')
-    assert FeedError('url').object_id == 'url'
-    assert EntryError('url', 'entry').object_id == ('url', 'entry')
+def test_resource_id():
+    assert Feed('url').resource_id == ('url',)
+    assert Entry('entry', 'updated', feed=Feed('url')).resource_id == ('url', 'entry')
+    assert EntrySearchResult('url', 'entry').resource_id == ('url', 'entry')
+    assert FeedData('url').resource_id == ('url',)
+    assert EntryData('url', 'entry', 'updated').resource_id == ('url', 'entry')
+    assert FeedError('url').resource_id == ('url',)
+    assert EntryError('url', 'entry').resource_id == ('url', 'entry')
 
 
 @pytest.mark.parametrize(
diff --git a/tests/test_utils.py b/tests/test_utils.py
index 296a14c7..15de8278 100644
--- a/tests/test_utils.py
+++ b/tests/test_utils.py
@@ -27,6 +27,35 @@ def old(arg):
     _check_deprecated(old)
 
 
+def test_deprecated_property():
+    class Class:
+        @property
+        @deprecated('new', '1.0', '2.0', property=True)
+        def old(self):
+            "docstring"
+            raise ValueError()
+
+    with pytest.raises(ValueError), pytest.deprecated_call() as warnings:
+        Class().old
+
+    assert Class.old.fget.__name__ == 'old'
+    assert Class.old.fget.__doc__ == (
+        'Deprecated variant of :attr:`new`.\n\n'
+        'docstring\n'
+        '\n'
+        '.. deprecated:: 1.0\n'
+        '    This property will be removed in *reader* 2.0.\n'
+        '    Use :attr:`new` instead.\n\n'
+    )
+
+    warning = warnings.pop()
+
+    assert (
+        str(warning.message)
+        == 'old is deprecated and will be removed in reader 2.0. Use new instead.'
+    )
+
+
 def _check_deprecated(old):
     with pytest.raises(ValueError) as excinfo, pytest.deprecated_call() as warnings:
         old('whatever')