diff --git a/packages/zarr-metadata/changes/4232.removal.md b/packages/zarr-metadata/changes/4232.removal.md
new file mode 100644
index 0000000000..73b2a18666
--- /dev/null
+++ b/packages/zarr-metadata/changes/4232.removal.md
@@ -0,0 +1,63 @@
+Unified the naming grammar for SCREAMING_SNAKE constants with the one used for
+type names. A constant's name is now a purely syntactic transformation of the
+name of the `Literal` type it manifests, so the format version is spelled
+`ZARR_V2`/`ZARR_V3` and comes first, matching the `ZarrV2`/`ZarrV3` prefix on
+the corresponding type:
+
+- `ARRAY_METADATA_STORE_KEY_V2` → `ZARR_V2_ARRAY_METADATA_STORE_KEY`
+- `ARRAY_METADATA_STORE_KEY_V3` → `ZARR_V3_ARRAY_METADATA_STORE_KEY`
+- `ATTRIBUTES_STORE_KEY_V2` → `ZARR_V2_ATTRIBUTES_STORE_KEY`
+- `GROUP_METADATA_STORE_KEY_V2` → `ZARR_V2_GROUP_METADATA_STORE_KEY`
+- `GROUP_METADATA_STORE_KEY_V3` → `ZARR_V3_GROUP_METADATA_STORE_KEY`
+- `CONSOLIDATED_METADATA_STORE_KEY_V2` → `ZARR_V2_CONSOLIDATED_METADATA_STORE_KEY`
+- `ARRAY_ORDER_V2` → `ZARR_V2_ARRAY_ORDER`
+- `ARRAY_DIMENSION_SEPARATOR_V2` → `ZARR_V2_ARRAY_DIMENSION_SEPARATOR`
+- `CONSOLIDATED_METADATA_KEY_V3` → `ZARR_V3_CONSOLIDATED_METADATA_KEY`
+
+The old names are removed, not aliased. This supersedes the 0.4.0 convention
+under which type names put the format version first while constants put it
+last: every constant that manifests a `Literal` type now follows the same rule
+as that type.
+
+The last of those is the one rename the syntactic rule does not force:
+`ZARR_V3_CONSOLIDATED_METADATA_KEY` manifests no `Literal` type, so it is
+outside the rule and was renamed for consistency with its siblings.
+
+Digit runs stay glued to the token they follow, so spec vocabulary is
+preserved: `Uint8DataTypeName` pairs with `UINT8_DATA_TYPE_NAME` (not
+`UINT_8_...`) and `Crc32cCodecName` with `CRC32C_CODEC_NAME`. No dtype, codec,
+chunk-grid, or chunk-key-encoding constant changed name.
+
+Constants that do not manifest a `Literal` type are outside the rule and are
+unchanged: the `*_METADATA_*_KEYS_V2`/`_V3` key sets, the
+`CANONICAL_*_HEX_FLOAT*` bit patterns, and `UNSET`. The key sets keep the
+version-last spelling, so `zarr_metadata.model` exports both
+`ARRAY_METADATA_REQUIRED_KEYS_V2` and `ZARR_V2_ARRAY_METADATA_STORE_KEY`. They
+name validation policy rather than a spec document, have no paired type to
+derive from, and renaming them would be a second breaking change buying only
+cosmetic consistency — so it is deliberately deferred.
+
+`tests/test_public_api.py::test_constant_names_derive_from_their_type_names`
+derives every constant name from the type it manifests and asserts they match,
+so the two grammars cannot diverge again.
+
+Store keys also moved to the modules that describe the documents they name,
+matching the package's layering (the `v2`/`v3` modules describe the specs; the
+`model` layer is built on top of them). `ZARR_V2_ATTRIBUTES_STORE_KEY` now
+lives in `zarr_metadata.v2.attributes` beside the `.zattrs` type it names,
+rather than in the array model; the other five moved likewise, and
+`ZarrV2AttributesStoreKey` is no longer an array-specific concept.
+`zarr_metadata.model` re-exports all six, so
+`from zarr_metadata.model import ZARR_V2_ARRAY_METADATA_STORE_KEY` is
+unaffected.
+
+`CONSOLIDATED_METADATA_KEY_V3` moved to `zarr_metadata.v3.consolidated` and was
+renamed to `ZARR_V3_CONSOLIDATED_METADATA_KEY` for consistency. It is not a
+store key: unlike v2's `.zmetadata` file, v3 consolidated metadata is embedded
+as an extension field inside the group's own `zarr.json`.
+
+All seven keys and the six store-key `Literal` aliases are now also exported
+from the top-level `zarr_metadata` namespace, alongside the document types and
+the rest of the spec vocabulary, so `from zarr_metadata import
+ZARR_V2_ARRAY_METADATA_STORE_KEY` works. The model layer's validators, parsers,
+type guards, and metadata key sets remain `zarr_metadata.model` imports.
diff --git a/packages/zarr-metadata/docs/api/index.md b/packages/zarr-metadata/docs/api/index.md
index 2aa39ab161..5e230c7aa2 100644
--- a/packages/zarr-metadata/docs/api/index.md
+++ b/packages/zarr-metadata/docs/api/index.md
@@ -17,9 +17,12 @@ The package is organized to mirror the structure of the Zarr specifications:
   [chunk key encodings](v3/chunk_key_encoding.md), [codecs](v3/codec.md),
   and [data types](v3/data_type.md)
 
-Every public name is also re-exported at the top level, so
+The document types, models, and spec vocabulary — including the store keys —
+are re-exported at the top level, so
 `from zarr_metadata import ZarrV3ArrayMetadataJSON` and
 `from zarr_metadata.v3.array import ZarrV3ArrayMetadataJSON` are equivalent.
+The model layer's validators, parsers, type guards, and metadata key sets are
+imported from [`zarr_metadata.model`](model.md) directly.
 
 ## Common types
 
diff --git a/packages/zarr-metadata/src/zarr_metadata/__init__.py b/packages/zarr-metadata/src/zarr_metadata/__init__.py
index b5e52e976d..1a6b39f04d 100644
--- a/packages/zarr-metadata/src/zarr_metadata/__init__.py
+++ b/packages/zarr-metadata/src/zarr_metadata/__init__.py
@@ -3,25 +3,38 @@
 from zarr_metadata._common import JSONValue, ZarrV3NamedConfigJSON
 from zarr_metadata.model import (
     UNSET,
+    ZARR_V2_ARRAY_METADATA_STORE_KEY,
+    ZARR_V2_ATTRIBUTES_STORE_KEY,
+    ZARR_V2_CONSOLIDATED_METADATA_STORE_KEY,
+    ZARR_V2_GROUP_METADATA_STORE_KEY,
+    ZARR_V3_ARRAY_METADATA_STORE_KEY,
+    ZARR_V3_CONSOLIDATED_METADATA_KEY,
+    ZARR_V3_GROUP_METADATA_STORE_KEY,
     MetadataValidationError,
     ProblemKind,
     ValidationProblem,
     ZarrV2ArrayMetadata,
     ZarrV2ArrayMetadataPartial,
+    ZarrV2ArrayMetadataStoreKey,
+    ZarrV2AttributesStoreKey,
     ZarrV2ConsolidatedMetadata,
+    ZarrV2ConsolidatedMetadataStoreKey,
     ZarrV2GroupMetadata,
     ZarrV2GroupMetadataPartial,
+    ZarrV2GroupMetadataStoreKey,
     ZarrV3ArrayMetadata,
     ZarrV3ArrayMetadataPartial,
+    ZarrV3ArrayMetadataStoreKey,
     ZarrV3ConsolidatedMetadata,
     ZarrV3GroupMetadata,
     ZarrV3GroupMetadataPartial,
+    ZarrV3GroupMetadataStoreKey,
     ZarrV3MetadataField,
     ZarrV3NamedConfig,
 )
 from zarr_metadata.v2.array import (
-    ARRAY_DIMENSION_SEPARATOR_V2,
-    ARRAY_ORDER_V2,
+    ZARR_V2_ARRAY_DIMENSION_SEPARATOR,
+    ZARR_V2_ARRAY_ORDER,
     ZarrV2ArrayDimensionSeparator,
     ZarrV2ArrayMetadataJSON,
     ZarrV2ArrayMetadataJSONPartial,
@@ -217,8 +230,6 @@
 
 
 __all__ = [
-    "ARRAY_DIMENSION_SEPARATOR_V2",
-    "ARRAY_ORDER_V2",
     "BLOSC_CNAME",
     "BLOSC_CODEC_NAME",
     "BLOSC_SHUFFLE",
@@ -260,6 +271,15 @@
     "UNSET",
     "V2_CHUNK_KEY_ENCODING_NAME",
     "V2_CHUNK_KEY_ENCODING_SEPARATOR",
+    "ZARR_V2_ARRAY_DIMENSION_SEPARATOR",
+    "ZARR_V2_ARRAY_METADATA_STORE_KEY",
+    "ZARR_V2_ARRAY_ORDER",
+    "ZARR_V2_ATTRIBUTES_STORE_KEY",
+    "ZARR_V2_CONSOLIDATED_METADATA_STORE_KEY",
+    "ZARR_V2_GROUP_METADATA_STORE_KEY",
+    "ZARR_V3_ARRAY_METADATA_STORE_KEY",
+    "ZARR_V3_CONSOLIDATED_METADATA_KEY",
+    "ZARR_V3_GROUP_METADATA_STORE_KEY",
     "ZSTD_CODEC_NAME",
     "BloscCName",
     "BloscCodecMetadata",
@@ -343,15 +363,19 @@
     "ZarrV2ArrayMetadataJSON",
     "ZarrV2ArrayMetadataJSONPartial",
     "ZarrV2ArrayMetadataPartial",
+    "ZarrV2ArrayMetadataStoreKey",
     "ZarrV2ArrayOrder",
+    "ZarrV2AttributesStoreKey",
     "ZarrV2CodecMetadata",
     "ZarrV2ConsolidatedMetadata",
     "ZarrV2ConsolidatedMetadataJSON",
+    "ZarrV2ConsolidatedMetadataStoreKey",
     "ZarrV2DataTypeMetadata",
     "ZarrV2GroupMetadata",
     "ZarrV2GroupMetadataJSON",
     "ZarrV2GroupMetadataJSONPartial",
     "ZarrV2GroupMetadataPartial",
+    "ZarrV2GroupMetadataStoreKey",
     "ZarrV2ZArrayJSON",
     "ZarrV2ZAttrsJSON",
     "ZarrV2ZGroupJSON",
@@ -359,6 +383,7 @@
     "ZarrV3ArrayMetadataJSON",
     "ZarrV3ArrayMetadataJSONPartial",
     "ZarrV3ArrayMetadataPartial",
+    "ZarrV3ArrayMetadataStoreKey",
     "ZarrV3ConsolidatedMetadata",
     "ZarrV3ConsolidatedMetadataJSON",
     "ZarrV3ExtensionField",
@@ -366,6 +391,7 @@
     "ZarrV3GroupMetadataJSON",
     "ZarrV3GroupMetadataJSONPartial",
     "ZarrV3GroupMetadataPartial",
+    "ZarrV3GroupMetadataStoreKey",
     "ZarrV3MetadataField",
     "ZarrV3MetadataFieldJSON",
     "ZarrV3NamedConfig",
diff --git a/packages/zarr-metadata/src/zarr_metadata/model/__init__.py b/packages/zarr-metadata/src/zarr_metadata/model/__init__.py
index e726c54d3e..edf3561d1d 100644
--- a/packages/zarr-metadata/src/zarr_metadata/model/__init__.py
+++ b/packages/zarr-metadata/src/zarr_metadata/model/__init__.py
@@ -12,33 +12,20 @@
 """
 
 from zarr_metadata.model._array import (
-    ARRAY_METADATA_STORE_KEY_V2,
-    ARRAY_METADATA_STORE_KEY_V3,
-    ATTRIBUTES_STORE_KEY_V2,
     ZarrV2ArrayMetadata,
     ZarrV2ArrayMetadataPartial,
-    ZarrV2ArrayMetadataStoreKey,
-    ZarrV2AttributesStoreKey,
     ZarrV3ArrayMetadata,
     ZarrV3ArrayMetadataPartial,
-    ZarrV3ArrayMetadataStoreKey,
     ZarrV3MetadataField,
     ZarrV3NamedConfig,
 )
 from zarr_metadata.model._group import (
-    CONSOLIDATED_METADATA_KEY_V3,
-    CONSOLIDATED_METADATA_STORE_KEY_V2,
-    GROUP_METADATA_STORE_KEY_V2,
-    GROUP_METADATA_STORE_KEY_V3,
     ZarrV2ConsolidatedMetadata,
-    ZarrV2ConsolidatedMetadataStoreKey,
     ZarrV2GroupMetadata,
     ZarrV2GroupMetadataPartial,
-    ZarrV2GroupMetadataStoreKey,
     ZarrV3ConsolidatedMetadata,
     ZarrV3GroupMetadata,
     ZarrV3GroupMetadataPartial,
-    ZarrV3GroupMetadataStoreKey,
 )
 from zarr_metadata.model._sentinel import UNSET
 from zarr_metadata.model._validation import (
@@ -73,23 +60,52 @@
     validate_metadata_field_v3,
 )
 
+# Store keys are facts about the on-disk specs, so they are defined in the
+# `v2`/`v3` modules that describe those documents. They are re-exported here
+# because the model layer is where consumers reach for them.
+from zarr_metadata.v2.array import (
+    ZARR_V2_ARRAY_METADATA_STORE_KEY,
+    ZarrV2ArrayMetadataStoreKey,
+)
+from zarr_metadata.v2.attributes import (
+    ZARR_V2_ATTRIBUTES_STORE_KEY,
+    ZarrV2AttributesStoreKey,
+)
+from zarr_metadata.v2.consolidated import (
+    ZARR_V2_CONSOLIDATED_METADATA_STORE_KEY,
+    ZarrV2ConsolidatedMetadataStoreKey,
+)
+from zarr_metadata.v2.group import (
+    ZARR_V2_GROUP_METADATA_STORE_KEY,
+    ZarrV2GroupMetadataStoreKey,
+)
+from zarr_metadata.v3.array import (
+    ZARR_V3_ARRAY_METADATA_STORE_KEY,
+    ZarrV3ArrayMetadataStoreKey,
+)
+from zarr_metadata.v3.consolidated import ZARR_V3_CONSOLIDATED_METADATA_KEY
+from zarr_metadata.v3.group import (
+    ZARR_V3_GROUP_METADATA_STORE_KEY,
+    ZarrV3GroupMetadataStoreKey,
+)
+
 __all__ = [
     "ARRAY_METADATA_OPTIONAL_KEYS_V3",
     "ARRAY_METADATA_REQUIRED_KEYS_V2",
     "ARRAY_METADATA_REQUIRED_KEYS_V3",
     "ARRAY_METADATA_STANDARD_KEYS_V3",
-    "ARRAY_METADATA_STORE_KEY_V2",
-    "ARRAY_METADATA_STORE_KEY_V3",
-    "ATTRIBUTES_STORE_KEY_V2",
-    "CONSOLIDATED_METADATA_KEY_V3",
-    "CONSOLIDATED_METADATA_STORE_KEY_V2",
     "GROUP_METADATA_OPTIONAL_KEYS_V3",
     "GROUP_METADATA_REQUIRED_KEYS_V2",
     "GROUP_METADATA_REQUIRED_KEYS_V3",
     "GROUP_METADATA_STANDARD_KEYS_V3",
-    "GROUP_METADATA_STORE_KEY_V2",
-    "GROUP_METADATA_STORE_KEY_V3",
     "UNSET",
+    "ZARR_V2_ARRAY_METADATA_STORE_KEY",
+    "ZARR_V2_ATTRIBUTES_STORE_KEY",
+    "ZARR_V2_CONSOLIDATED_METADATA_STORE_KEY",
+    "ZARR_V2_GROUP_METADATA_STORE_KEY",
+    "ZARR_V3_ARRAY_METADATA_STORE_KEY",
+    "ZARR_V3_CONSOLIDATED_METADATA_KEY",
+    "ZARR_V3_GROUP_METADATA_STORE_KEY",
     "MetadataValidationError",
     "ProblemKind",
     "ValidationProblem",
diff --git a/packages/zarr-metadata/src/zarr_metadata/model/_array.py b/packages/zarr-metadata/src/zarr_metadata/model/_array.py
index c4c967f891..0b562bc188 100644
--- a/packages/zarr-metadata/src/zarr_metadata/model/_array.py
+++ b/packages/zarr-metadata/src/zarr_metadata/model/_array.py
@@ -6,7 +6,7 @@
 import dataclasses
 from collections.abc import Mapping
 from dataclasses import dataclass, field
-from typing import TYPE_CHECKING, Final, Literal, TypeAlias, cast
+from typing import TYPE_CHECKING, Literal, TypeAlias, cast
 
 from typing_extensions import TypedDict, Unpack
 
@@ -22,27 +22,27 @@
     parse_array_metadata_v3,
     parse_metadata_field_v3,
 )
+from zarr_metadata.v2.array import ZARR_V2_ARRAY_METADATA_STORE_KEY
+from zarr_metadata.v2.attributes import ZARR_V2_ATTRIBUTES_STORE_KEY
+from zarr_metadata.v3.array import ZARR_V3_ARRAY_METADATA_STORE_KEY
 
 if TYPE_CHECKING:
     from zarr_metadata._common import JSONValue, ZarrV3NamedConfigJSON
     from zarr_metadata.v2.array import (
         ZarrV2ArrayDimensionSeparator,
         ZarrV2ArrayMetadataJSON,
+        ZarrV2ArrayMetadataStoreKey,
         ZarrV2ArrayOrder,
         ZarrV2DataTypeMetadata,
     )
+    from zarr_metadata.v2.attributes import ZarrV2AttributesStoreKey
     from zarr_metadata.v2.codec import ZarrV2CodecMetadata
     from zarr_metadata.v3._common import ZarrV3MetadataFieldJSON
-    from zarr_metadata.v3.array import ZarrV3ArrayMetadataJSON, ZarrV3ExtensionField
-
-ZarrV3ArrayMetadataStoreKey = Literal["zarr.json"]
-ARRAY_METADATA_STORE_KEY_V3: Final[ZarrV3ArrayMetadataStoreKey] = "zarr.json"
-
-ZarrV2ArrayMetadataStoreKey = Literal[".zarray"]
-ARRAY_METADATA_STORE_KEY_V2: Final[ZarrV2ArrayMetadataStoreKey] = ".zarray"
-
-ZarrV2AttributesStoreKey = Literal[".zattrs"]
-ATTRIBUTES_STORE_KEY_V2: Final[ZarrV2AttributesStoreKey] = ".zattrs"
+    from zarr_metadata.v3.array import (
+        ZarrV3ArrayMetadataJSON,
+        ZarrV3ArrayMetadataStoreKey,
+        ZarrV3ExtensionField,
+    )
 
 
 @dataclass(frozen=True, slots=True, kw_only=True)
@@ -319,12 +319,12 @@ def must_understand_fields(self) -> dict[str, ZarrV3ExtensionField]:
 
     @classmethod
     def from_key_value(cls, mapping: Mapping[str, bytes]) -> ZarrV3ArrayMetadata:
-        return cls.from_json(load_store_json(mapping, ARRAY_METADATA_STORE_KEY_V3))
+        return cls.from_json(load_store_json(mapping, ZARR_V3_ARRAY_METADATA_STORE_KEY))
 
     def to_key_value(
         self, *, indent: int | str | None = None
     ) -> Mapping[ZarrV3ArrayMetadataStoreKey, bytes]:
-        return {ARRAY_METADATA_STORE_KEY_V3: dump_store_json(self.to_json(), indent=indent)}
+        return {ZARR_V3_ARRAY_METADATA_STORE_KEY: dump_store_json(self.to_json(), indent=indent)}
 
 
 class ZarrV2ArrayMetadataPartial(TypedDict, total=False):
@@ -464,7 +464,7 @@ def from_json(cls, data: object) -> ZarrV2ArrayMetadata:
 
     @classmethod
     def from_key_value(cls, mapping: Mapping[str, bytes]) -> ZarrV2ArrayMetadata:
-        zarray_raw = cast("object", load_store_json(mapping, ARRAY_METADATA_STORE_KEY_V2))
+        zarray_raw = cast("object", load_store_json(mapping, ZARR_V2_ARRAY_METADATA_STORE_KEY))
         if not isinstance(zarray_raw, Mapping):
             return cls.from_json(zarray_raw)
         zarray = cast("Mapping[str, object]", zarray_raw)
@@ -478,8 +478,8 @@ def from_key_value(cls, mapping: Mapping[str, bytes]) -> ZarrV2ArrayMetadata:
                     )
                 ]
             )
-        if ATTRIBUTES_STORE_KEY_V2 in mapping:
-            zattrs = cast("object", load_store_json(mapping, ATTRIBUTES_STORE_KEY_V2))
+        if ZARR_V2_ATTRIBUTES_STORE_KEY in mapping:
+            zattrs = cast("object", load_store_json(mapping, ZARR_V2_ATTRIBUTES_STORE_KEY))
             return cls.from_json({**zarray, "attributes": zattrs})
         return cls.from_json(zarray)
 
@@ -491,8 +491,8 @@ def to_key_value(
         # when attributes are set (even empty) — UNSET emits no file.
         zarray = {k: v for k, v in self.to_json().items() if k != "attributes"}
         out: dict[ZarrV2ArrayMetadataStoreKey | ZarrV2AttributesStoreKey, bytes] = {
-            ARRAY_METADATA_STORE_KEY_V2: dump_store_json(zarray, indent=indent)
+            ZARR_V2_ARRAY_METADATA_STORE_KEY: dump_store_json(zarray, indent=indent)
         }
         if self.attributes is not UNSET:
-            out[ATTRIBUTES_STORE_KEY_V2] = dump_store_json(self.attributes, indent=indent)
+            out[ZARR_V2_ATTRIBUTES_STORE_KEY] = dump_store_json(self.attributes, indent=indent)
         return out
diff --git a/packages/zarr-metadata/src/zarr_metadata/model/_group.py b/packages/zarr-metadata/src/zarr_metadata/model/_group.py
index d576833c26..63dfe5611f 100644
--- a/packages/zarr-metadata/src/zarr_metadata/model/_group.py
+++ b/packages/zarr-metadata/src/zarr_metadata/model/_group.py
@@ -6,12 +6,11 @@
 import dataclasses
 from collections.abc import Mapping
 from dataclasses import dataclass, field
-from typing import TYPE_CHECKING, Final, Literal, cast
+from typing import TYPE_CHECKING, Literal, cast
 
 from typing_extensions import TypedDict, Unpack
 
 from zarr_metadata.model._array import (
-    ATTRIBUTES_STORE_KEY_V2,
     ZarrV3ArrayMetadata,
     must_understand_subset,
 )
@@ -28,28 +27,20 @@
     validate_consolidated_metadata_v3,
     validate_json,
 )
+from zarr_metadata.v2.attributes import ZARR_V2_ATTRIBUTES_STORE_KEY
+from zarr_metadata.v2.consolidated import ZARR_V2_CONSOLIDATED_METADATA_STORE_KEY
+from zarr_metadata.v2.group import ZARR_V2_GROUP_METADATA_STORE_KEY
+from zarr_metadata.v3.consolidated import ZARR_V3_CONSOLIDATED_METADATA_KEY
+from zarr_metadata.v3.group import ZARR_V3_GROUP_METADATA_STORE_KEY
 
 if TYPE_CHECKING:
     from zarr_metadata._common import JSONValue
-    from zarr_metadata.model._array import ZarrV2AttributesStoreKey
-    from zarr_metadata.v2.group import ZarrV2GroupMetadataJSON
+    from zarr_metadata.v2.attributes import ZarrV2AttributesStoreKey
+    from zarr_metadata.v2.consolidated import ZarrV2ConsolidatedMetadataStoreKey
+    from zarr_metadata.v2.group import ZarrV2GroupMetadataJSON, ZarrV2GroupMetadataStoreKey
     from zarr_metadata.v3.array import ZarrV3ExtensionField
     from zarr_metadata.v3.consolidated import ZarrV3ConsolidatedMetadataJSON
-    from zarr_metadata.v3.group import ZarrV3GroupMetadataJSON
-
-ZarrV3GroupMetadataStoreKey = Literal["zarr.json"]
-GROUP_METADATA_STORE_KEY_V3: Final[ZarrV3GroupMetadataStoreKey] = "zarr.json"
-
-ZarrV2GroupMetadataStoreKey = Literal[".zgroup"]
-GROUP_METADATA_STORE_KEY_V2: Final[ZarrV2GroupMetadataStoreKey] = ".zgroup"
-
-ZarrV2ConsolidatedMetadataStoreKey = Literal[".zmetadata"]
-CONSOLIDATED_METADATA_STORE_KEY_V2: Final[ZarrV2ConsolidatedMetadataStoreKey] = ".zmetadata"
-
-# The key under which consolidated metadata is embedded in a v3 group document.
-# This is a reference-implementation convention (not a spec artifact), stored
-# as an extension field on the group's `zarr.json`.
-CONSOLIDATED_METADATA_KEY_V3: Final = "consolidated_metadata"
+    from zarr_metadata.v3.group import ZarrV3GroupMetadataJSON, ZarrV3GroupMetadataStoreKey
 
 
 class ZarrV3GroupMetadataPartial(TypedDict, total=False):
@@ -88,7 +79,7 @@ class ZarrV3GroupMetadata:
     extra_fields: dict[str, ZarrV3ExtensionField]
 
     def __post_init__(self) -> None:
-        reserved = GROUP_METADATA_STANDARD_KEYS_V3 | {CONSOLIDATED_METADATA_KEY_V3}
+        reserved = GROUP_METADATA_STANDARD_KEYS_V3 | {ZARR_V3_CONSOLIDATED_METADATA_KEY}
         if set(self.extra_fields.keys()).intersection(reserved):
             raise MetadataValidationError(
                 [
@@ -134,7 +125,7 @@ def to_json(self) -> ZarrV3GroupMetadataJSON:
             out["attributes"] = copy.deepcopy(self.attributes)
         if self.consolidated_metadata is not UNSET:
             # Consolidated metadata is a known non-core top-level JSON field.
-            out[CONSOLIDATED_METADATA_KEY_V3] = cast(
+            out[ZARR_V3_CONSOLIDATED_METADATA_KEY] = cast(
                 "ZarrV3ExtensionField", self.consolidated_metadata.to_json()
             )
         for key, value in self.extra_fields.items():
@@ -145,7 +136,7 @@ def to_json(self) -> ZarrV3GroupMetadataJSON:
     def from_json(cls, data: object) -> ZarrV3GroupMetadata:
         parsed = parse_group_metadata_v3(arrays_to_tuples(data))
         # Cast for narrowing across standard and arbitrary extra TypedDict items.
-        consolidated_raw = cast("object", parsed.get(CONSOLIDATED_METADATA_KEY_V3, UNSET))
+        consolidated_raw = cast("object", parsed.get(ZARR_V3_CONSOLIDATED_METADATA_KEY, UNSET))
         consolidated: ZarrV3ConsolidatedMetadata | UNSET
         if consolidated_raw is UNSET or consolidated_raw is None:
             # consolidated_metadata: null was written by a historical
@@ -162,7 +153,8 @@ def from_json(cls, data: object) -> ZarrV3GroupMetadata:
             {
                 k: v
                 for k, v in parsed.items()
-                if k not in GROUP_METADATA_STANDARD_KEYS_V3 and k != CONSOLIDATED_METADATA_KEY_V3
+                if k not in GROUP_METADATA_STANDARD_KEYS_V3
+                and k != ZARR_V3_CONSOLIDATED_METADATA_KEY
             },
         )
         return cls(
@@ -185,12 +177,12 @@ def must_understand_fields(self) -> dict[str, ZarrV3ExtensionField]:
 
     @classmethod
     def from_key_value(cls, mapping: Mapping[str, bytes]) -> ZarrV3GroupMetadata:
-        return cls.from_json(load_store_json(mapping, GROUP_METADATA_STORE_KEY_V3))
+        return cls.from_json(load_store_json(mapping, ZARR_V3_GROUP_METADATA_STORE_KEY))
 
     def to_key_value(
         self, *, indent: int | str | None = None
     ) -> Mapping[ZarrV3GroupMetadataStoreKey, bytes]:
-        return {GROUP_METADATA_STORE_KEY_V3: dump_store_json(self.to_json(), indent=indent)}
+        return {ZARR_V3_GROUP_METADATA_STORE_KEY: dump_store_json(self.to_json(), indent=indent)}
 
 
 @dataclass(frozen=True, slots=True, kw_only=True)
@@ -322,7 +314,7 @@ def from_json(cls, data: object) -> ZarrV2GroupMetadata:
 
     @classmethod
     def from_key_value(cls, mapping: Mapping[str, bytes]) -> ZarrV2GroupMetadata:
-        zgroup_raw = cast("object", load_store_json(mapping, GROUP_METADATA_STORE_KEY_V2))
+        zgroup_raw = cast("object", load_store_json(mapping, ZARR_V2_GROUP_METADATA_STORE_KEY))
         if not isinstance(zgroup_raw, Mapping):
             return cls.from_json(zgroup_raw)
         zgroup = cast("Mapping[str, object]", zgroup_raw)
@@ -336,8 +328,8 @@ def from_key_value(cls, mapping: Mapping[str, bytes]) -> ZarrV2GroupMetadata:
                     )
                 ]
             )
-        if ATTRIBUTES_STORE_KEY_V2 in mapping:
-            zattrs = cast("object", load_store_json(mapping, ATTRIBUTES_STORE_KEY_V2))
+        if ZARR_V2_ATTRIBUTES_STORE_KEY in mapping:
+            zattrs = cast("object", load_store_json(mapping, ZARR_V2_ATTRIBUTES_STORE_KEY))
             return cls.from_json({**zgroup, "attributes": zattrs})
         return cls.from_json(zgroup)
 
@@ -349,10 +341,10 @@ def to_key_value(
         # when attributes are set (even empty) — UNSET emits no file.
         zgroup = {k: v for k, v in self.to_json().items() if k != "attributes"}
         out: dict[ZarrV2GroupMetadataStoreKey | ZarrV2AttributesStoreKey, bytes] = {
-            GROUP_METADATA_STORE_KEY_V2: dump_store_json(zgroup, indent=indent)
+            ZARR_V2_GROUP_METADATA_STORE_KEY: dump_store_json(zgroup, indent=indent)
         }
         if self.attributes is not UNSET:
-            out[ATTRIBUTES_STORE_KEY_V2] = dump_store_json(self.attributes, indent=indent)
+            out[ZARR_V2_ATTRIBUTES_STORE_KEY] = dump_store_json(self.attributes, indent=indent)
         return out
 
 
@@ -434,9 +426,11 @@ def from_json(cls, data: object) -> ZarrV2ConsolidatedMetadata:
 
     @classmethod
     def from_key_value(cls, mapping: Mapping[str, bytes]) -> ZarrV2ConsolidatedMetadata:
-        return cls.from_json(load_store_json(mapping, CONSOLIDATED_METADATA_STORE_KEY_V2))
+        return cls.from_json(load_store_json(mapping, ZARR_V2_CONSOLIDATED_METADATA_STORE_KEY))
 
     def to_key_value(
         self, *, indent: int | str | None = None
     ) -> Mapping[ZarrV2ConsolidatedMetadataStoreKey, bytes]:
-        return {CONSOLIDATED_METADATA_STORE_KEY_V2: dump_store_json(self.to_json(), indent=indent)}
+        return {
+            ZARR_V2_CONSOLIDATED_METADATA_STORE_KEY: dump_store_json(self.to_json(), indent=indent)
+        }
diff --git a/packages/zarr-metadata/src/zarr_metadata/v2/array.py b/packages/zarr-metadata/src/zarr_metadata/v2/array.py
index 84b6446bcb..e026e5c655 100644
--- a/packages/zarr-metadata/src/zarr_metadata/v2/array.py
+++ b/packages/zarr-metadata/src/zarr_metadata/v2/array.py
@@ -39,7 +39,7 @@
 See https://zarr-specs.readthedocs.io/en/latest/v2/v2.0.html
 """
 
-ARRAY_ORDER_V2: Final = ("C", "F")
+ZARR_V2_ARRAY_ORDER: Final = ("C", "F")
 """Tuple of permitted values for the `order` field of v2 array metadata."""
 
 ZarrV2ArrayDimensionSeparator = Literal[".", "/"]
@@ -51,7 +51,7 @@
 See https://zarr-specs.readthedocs.io/en/latest/v2/v2.0.html
 """
 
-ARRAY_DIMENSION_SEPARATOR_V2: Final = (".", "/")
+ZARR_V2_ARRAY_DIMENSION_SEPARATOR: Final = (".", "/")
 """Tuple of permitted values for the `dimension_separator` field of v2 array metadata."""
 
 
@@ -149,12 +149,21 @@ class ZarrV2ArrayMetadataJSONPartial(TypedDict, total=False):
     """
 
 
+ZarrV2ArrayMetadataStoreKey = Literal[".zarray"]
+"""Literal type of the store key holding a v2 array's metadata document."""
+
+ZARR_V2_ARRAY_METADATA_STORE_KEY: Final[ZarrV2ArrayMetadataStoreKey] = ".zarray"
+"""The store key a v2 array's metadata document is persisted under."""
+
+
 __all__ = [
-    "ARRAY_DIMENSION_SEPARATOR_V2",
-    "ARRAY_ORDER_V2",
+    "ZARR_V2_ARRAY_DIMENSION_SEPARATOR",
+    "ZARR_V2_ARRAY_METADATA_STORE_KEY",
+    "ZARR_V2_ARRAY_ORDER",
     "ZarrV2ArrayDimensionSeparator",
     "ZarrV2ArrayMetadataJSON",
     "ZarrV2ArrayMetadataJSONPartial",
+    "ZarrV2ArrayMetadataStoreKey",
     "ZarrV2ArrayOrder",
     "ZarrV2DataTypeMetadata",
     "ZarrV2ZArrayJSON",
diff --git a/packages/zarr-metadata/src/zarr_metadata/v2/attributes.py b/packages/zarr-metadata/src/zarr_metadata/v2/attributes.py
index f7cc31babe..68785d1660 100644
--- a/packages/zarr-metadata/src/zarr_metadata/v2/attributes.py
+++ b/packages/zarr-metadata/src/zarr_metadata/v2/attributes.py
@@ -4,6 +4,7 @@
 """
 
 from collections.abc import Mapping
+from typing import Final, Literal
 
 from zarr_metadata._common import JSONValue
 
@@ -17,6 +18,19 @@
 """
 
 
+ZarrV2AttributesStoreKey = Literal[".zattrs"]
+"""Literal type of the store key holding a v2 node's user attributes."""
+
+ZARR_V2_ATTRIBUTES_STORE_KEY: Final[ZarrV2AttributesStoreKey] = ".zattrs"
+"""The store key a v2 node's user attributes are persisted under.
+
+Shared by arrays and groups: both node types keep their attributes in a
+sibling `.zattrs` file.
+"""
+
+
 __all__ = [
+    "ZARR_V2_ATTRIBUTES_STORE_KEY",
+    "ZarrV2AttributesStoreKey",
     "ZarrV2ZAttrsJSON",
 ]
diff --git a/packages/zarr-metadata/src/zarr_metadata/v2/consolidated.py b/packages/zarr-metadata/src/zarr_metadata/v2/consolidated.py
index 6b586bb92e..999c9131da 100644
--- a/packages/zarr-metadata/src/zarr_metadata/v2/consolidated.py
+++ b/packages/zarr-metadata/src/zarr_metadata/v2/consolidated.py
@@ -7,6 +7,7 @@
 """
 
 from collections.abc import Mapping
+from typing import Final, Literal
 
 from typing_extensions import TypedDict
 
@@ -37,6 +38,19 @@ class ZarrV2ConsolidatedMetadataJSON(TypedDict):
     metadata: Mapping[str, ZarrV2ZArrayJSON | ZarrV2ZGroupJSON | ZarrV2ZAttrsJSON]
 
 
+ZarrV2ConsolidatedMetadataStoreKey = Literal[".zmetadata"]
+"""Literal type of the store key holding a v2 hierarchy's consolidated metadata."""
+
+ZARR_V2_CONSOLIDATED_METADATA_STORE_KEY: Final[ZarrV2ConsolidatedMetadataStoreKey] = ".zmetadata"
+"""The store key a v2 hierarchy's consolidated metadata is persisted under.
+
+Like the document it names, this is a reference-implementation convention
+rather than a spec artifact; see the module docstring.
+"""
+
+
 __all__ = [
+    "ZARR_V2_CONSOLIDATED_METADATA_STORE_KEY",
     "ZarrV2ConsolidatedMetadataJSON",
+    "ZarrV2ConsolidatedMetadataStoreKey",
 ]
diff --git a/packages/zarr-metadata/src/zarr_metadata/v2/group.py b/packages/zarr-metadata/src/zarr_metadata/v2/group.py
index 50f2482e6f..34d72742c2 100644
--- a/packages/zarr-metadata/src/zarr_metadata/v2/group.py
+++ b/packages/zarr-metadata/src/zarr_metadata/v2/group.py
@@ -4,7 +4,7 @@
 """
 
 from collections.abc import Mapping
-from typing import Literal, NotRequired
+from typing import Final, Literal, NotRequired
 
 from typing_extensions import TypedDict
 
@@ -74,8 +74,17 @@ class ZarrV2GroupMetadataJSONPartial(TypedDict, total=False):
     attributes: NotRequired[Mapping[str, JSONValue]]
 
 
+ZarrV2GroupMetadataStoreKey = Literal[".zgroup"]
+"""Literal type of the store key holding a v2 group's metadata document."""
+
+ZARR_V2_GROUP_METADATA_STORE_KEY: Final[ZarrV2GroupMetadataStoreKey] = ".zgroup"
+"""The store key a v2 group's metadata document is persisted under."""
+
+
 __all__ = [
+    "ZARR_V2_GROUP_METADATA_STORE_KEY",
     "ZarrV2GroupMetadataJSON",
     "ZarrV2GroupMetadataJSONPartial",
+    "ZarrV2GroupMetadataStoreKey",
     "ZarrV2ZGroupJSON",
 ]
diff --git a/packages/zarr-metadata/src/zarr_metadata/v3/array.py b/packages/zarr-metadata/src/zarr_metadata/v3/array.py
index 96341f73ca..31a5f6b755 100644
--- a/packages/zarr-metadata/src/zarr_metadata/v3/array.py
+++ b/packages/zarr-metadata/src/zarr_metadata/v3/array.py
@@ -1,7 +1,7 @@
 """Zarr v3 array metadata types."""
 
 from collections.abc import Mapping
-from typing import Literal, NotRequired, TypeAlias
+from typing import Final, Literal, NotRequired, TypeAlias
 
 from typing_extensions import TypedDict
 
@@ -75,8 +75,21 @@ class ZarrV3ArrayMetadataJSONPartial(TypedDict, total=False, extra_items=ZarrV3E
     dimension_names: NotRequired[tuple[str | None, ...]]
 
 
+ZarrV3ArrayMetadataStoreKey = Literal["zarr.json"]
+"""Literal type of the store key holding a v3 array's metadata document."""
+
+ZARR_V3_ARRAY_METADATA_STORE_KEY: Final[ZarrV3ArrayMetadataStoreKey] = "zarr.json"
+"""The store key a v3 array's metadata document is persisted under.
+
+v3 uses one key for both node types; the document's `node_type` field
+distinguishes an array from a group.
+"""
+
+
 __all__ = [
+    "ZARR_V3_ARRAY_METADATA_STORE_KEY",
     "ZarrV3ArrayMetadataJSON",
     "ZarrV3ArrayMetadataJSONPartial",
+    "ZarrV3ArrayMetadataStoreKey",
     "ZarrV3ExtensionField",
 ]
diff --git a/packages/zarr-metadata/src/zarr_metadata/v3/consolidated.py b/packages/zarr-metadata/src/zarr_metadata/v3/consolidated.py
index bcbe675947..a9fe0c1f8f 100644
--- a/packages/zarr-metadata/src/zarr_metadata/v3/consolidated.py
+++ b/packages/zarr-metadata/src/zarr_metadata/v3/consolidated.py
@@ -12,7 +12,7 @@
 """
 
 from collections.abc import Mapping
-from typing import Literal
+from typing import Final, Literal
 
 from typing_extensions import TypedDict
 
@@ -34,6 +34,16 @@ class ZarrV3ConsolidatedMetadataJSON(TypedDict):
     metadata: Mapping[str, ZarrV3ArrayMetadataJSON | ZarrV3GroupMetadataJSON]
 
 
+ZARR_V3_CONSOLIDATED_METADATA_KEY: Final = "consolidated_metadata"
+"""The key under which consolidated metadata is embedded in a v3 group document.
+
+Unlike the v2 `.zmetadata` file, this is not a store key: consolidated metadata
+is carried as an extension field inside the group's own `zarr.json`. Like its v2
+counterpart it is a reference-implementation convention, not a spec artifact.
+"""
+
+
 __all__ = [
+    "ZARR_V3_CONSOLIDATED_METADATA_KEY",
     "ZarrV3ConsolidatedMetadataJSON",
 ]
diff --git a/packages/zarr-metadata/src/zarr_metadata/v3/group.py b/packages/zarr-metadata/src/zarr_metadata/v3/group.py
index 033e91ff8c..37bfdd6934 100644
--- a/packages/zarr-metadata/src/zarr_metadata/v3/group.py
+++ b/packages/zarr-metadata/src/zarr_metadata/v3/group.py
@@ -4,7 +4,7 @@
 """
 
 from collections.abc import Mapping
-from typing import Literal, NotRequired
+from typing import Final, Literal, NotRequired
 
 from typing_extensions import TypedDict
 
@@ -54,7 +54,20 @@ class ZarrV3GroupMetadataJSONPartial(TypedDict, total=False, extra_items=ZarrV3E
     attributes: NotRequired[Mapping[str, JSONValue]]
 
 
+ZarrV3GroupMetadataStoreKey = Literal["zarr.json"]
+"""Literal type of the store key holding a v3 group's metadata document."""
+
+ZARR_V3_GROUP_METADATA_STORE_KEY: Final[ZarrV3GroupMetadataStoreKey] = "zarr.json"
+"""The store key a v3 group's metadata document is persisted under.
+
+v3 uses one key for both node types; the document's `node_type` field
+distinguishes a group from an array.
+"""
+
+
 __all__ = [
+    "ZARR_V3_GROUP_METADATA_STORE_KEY",
     "ZarrV3GroupMetadataJSON",
     "ZarrV3GroupMetadataJSONPartial",
+    "ZarrV3GroupMetadataStoreKey",
 ]
diff --git a/packages/zarr-metadata/tests/model/test_array.py b/packages/zarr-metadata/tests/model/test_array.py
index 467ef1e2ad..95dc7aea3a 100644
--- a/packages/zarr-metadata/tests/model/test_array.py
+++ b/packages/zarr-metadata/tests/model/test_array.py
@@ -64,25 +64,71 @@ def test_guards_exported_from_package() -> None:
         assert hasattr(zarr_metadata.model, name)
 
 
+# `ZARR_V3_CONSOLIDATED_METADATA_KEY` is deliberately absent: it names a key
+# *inside* a v3 group document, not a store key, so it has no paired `Literal`
+# and no `to_key_value` signature to appear in. See `test_v3_consolidated_key_
+# is_not_a_store_key`, which pins that distinction.
+STORE_KEY_PAIRS = [
+    ("ZARR_V2_ARRAY_METADATA_STORE_KEY", "ZarrV2ArrayMetadataStoreKey", "zarr_metadata.v2.array"),
+    ("ZARR_V3_ARRAY_METADATA_STORE_KEY", "ZarrV3ArrayMetadataStoreKey", "zarr_metadata.v3.array"),
+    ("ZARR_V2_ATTRIBUTES_STORE_KEY", "ZarrV2AttributesStoreKey", "zarr_metadata.v2.attributes"),
+    ("ZARR_V2_GROUP_METADATA_STORE_KEY", "ZarrV2GroupMetadataStoreKey", "zarr_metadata.v2.group"),
+    ("ZARR_V3_GROUP_METADATA_STORE_KEY", "ZarrV3GroupMetadataStoreKey", "zarr_metadata.v3.group"),
+    (
+        "ZARR_V2_CONSOLIDATED_METADATA_STORE_KEY",
+        "ZarrV2ConsolidatedMetadataStoreKey",
+        "zarr_metadata.v2.consolidated",
+    ),
+]
+
+
 def test_store_key_pairs_exported_from_package() -> None:
     """Each store-key constant is exported together with its Literal type
     alias, and the pair cannot drift apart."""
     import zarr_metadata.model as m
 
-    pairs = [
-        ("ARRAY_METADATA_STORE_KEY_V2", "ZarrV2ArrayMetadataStoreKey"),
-        ("ARRAY_METADATA_STORE_KEY_V3", "ZarrV3ArrayMetadataStoreKey"),
-        ("ATTRIBUTES_STORE_KEY_V2", "ZarrV2AttributesStoreKey"),
-        ("GROUP_METADATA_STORE_KEY_V2", "ZarrV2GroupMetadataStoreKey"),
-        ("GROUP_METADATA_STORE_KEY_V3", "ZarrV3GroupMetadataStoreKey"),
-        ("CONSOLIDATED_METADATA_STORE_KEY_V2", "ZarrV2ConsolidatedMetadataStoreKey"),
-    ]
-    for const_name, alias_name in pairs:
+    for const_name, alias_name, _ in STORE_KEY_PAIRS:
         assert const_name in m.__all__
         assert alias_name in m.__all__
         assert (getattr(m, const_name),) == get_args(getattr(m, alias_name))
 
 
+def test_store_keys_are_defined_in_their_spec_modules() -> None:
+    """Store keys are facts about the on-disk specs, so each is defined in the
+    `v2`/`v3` module describing that document — not in the model layer, which
+    only re-exports them."""
+    import importlib
+
+    for const_name, alias_name, module_name in STORE_KEY_PAIRS:
+        module = importlib.import_module(module_name)
+        for name in (const_name, alias_name):
+            assert name in module.__all__, f"{name} should be exported by {module_name}"
+
+
+def test_v3_consolidated_key_is_not_a_store_key() -> None:
+    """v3 consolidated metadata is embedded as a field inside the group's own
+    `zarr.json`, not persisted under its own store key. It therefore has no
+    paired `Literal` alias, unlike every true store key — which is why it is
+    excluded from `STORE_KEY_PAIRS` rather than merely forgotten."""
+    import zarr_metadata.model as m
+
+    assert "ZARR_V3_CONSOLIDATED_METADATA_KEY" in m.__all__
+    assert not hasattr(m, "ZarrV3ConsolidatedMetadataKey")
+    assert m.ZARR_V3_CONSOLIDATED_METADATA_KEY not in {
+        getattr(m, const_name) for const_name, _, _ in STORE_KEY_PAIRS
+    }
+
+
+def test_v3_node_store_keys_agree() -> None:
+    """v3 keys both node types' metadata under one store key, distinguished by
+    the document's `node_type`. The array and group constants are separately
+    typed but must name the same file; adjacency used to make that obvious, and
+    they now live in different modules."""
+    import zarr_metadata.model as m
+
+    assert m.ZARR_V3_ARRAY_METADATA_STORE_KEY == m.ZARR_V3_GROUP_METADATA_STORE_KEY
+
+
 def test_validation_diagnostics_exported_from_package() -> None:
     """The validation-diagnostic types and validators are exported from the package."""
     import zarr_metadata.model
diff --git a/packages/zarr-metadata/tests/test_public_api.py b/packages/zarr-metadata/tests/test_public_api.py
index e65c680fd1..6613aa394b 100644
--- a/packages/zarr-metadata/tests/test_public_api.py
+++ b/packages/zarr-metadata/tests/test_public_api.py
@@ -3,7 +3,7 @@
 import importlib
 import pkgutil
 import re
-from typing import get_args
+from typing import Literal, get_args, get_origin
 
 import zarr_metadata as zm
 
@@ -58,6 +58,23 @@ def _group_rank(s: str) -> int:
     "MetadataValidationError",
     "ProblemKind",
     "UNSET",
+    # Store keys — the names the documents are persisted under. Defined in the
+    # v2/v3 spec modules, re-exported through `zarr_metadata.model`.
+    "ZARR_V2_ARRAY_METADATA_STORE_KEY",
+    "ZarrV2ArrayMetadataStoreKey",
+    "ZARR_V2_GROUP_METADATA_STORE_KEY",
+    "ZarrV2GroupMetadataStoreKey",
+    "ZARR_V2_ATTRIBUTES_STORE_KEY",
+    "ZarrV2AttributesStoreKey",
+    "ZARR_V2_CONSOLIDATED_METADATA_STORE_KEY",
+    "ZarrV2ConsolidatedMetadataStoreKey",
+    "ZARR_V3_ARRAY_METADATA_STORE_KEY",
+    "ZarrV3ArrayMetadataStoreKey",
+    "ZARR_V3_GROUP_METADATA_STORE_KEY",
+    "ZarrV3GroupMetadataStoreKey",
+    # Not a store key: v3 consolidated metadata is embedded in the group's own
+    # `zarr.json`, so it has no paired Literal alias.
+    "ZARR_V3_CONSOLIDATED_METADATA_KEY",
     # v2 data-type encoding union
     "ZarrV2DataTypeMetadata",
     # Category B — codec canonical unions
@@ -147,9 +164,9 @@ def _group_rank(s: str) -> int:
     "RawBytesDataTypeName",
     "RawBytesFillValue",
     # Category E — constant+Literal pairs
-    "ARRAY_ORDER_V2",
+    "ZARR_V2_ARRAY_ORDER",
     "ZarrV2ArrayOrder",
-    "ARRAY_DIMENSION_SEPARATOR_V2",
+    "ZARR_V2_ARRAY_DIMENSION_SEPARATOR",
     "ZarrV2ArrayDimensionSeparator",
     "ENDIANNESS",
     "Endianness",
@@ -285,14 +302,19 @@ def test_all_is_grouped_and_unique() -> None:
 )
 
 
-def _public_type_names() -> set[tuple[str, str]]:
-    """Every (module, CamelCase name) pair exported via a public `__all__`."""
+def _iter_module_names() -> set[str]:
+    """Every public module in the package, including the top-level namespace."""
     module_names = {"zarr_metadata"}
     for info in pkgutil.walk_packages(zm.__path__, prefix="zarr_metadata."):
         if not any(part.startswith("_") for part in info.name.split(".")[1:]):
             module_names.add(info.name)
+    return module_names
+
+
+def _public_type_names() -> set[tuple[str, str]]:
+    """Every (module, CamelCase name) pair exported via a public `__all__`."""
     out: set[tuple[str, str]] = set()
-    for module_name in module_names:
+    for module_name in _iter_module_names():
         module = importlib.import_module(module_name)
         for name in getattr(module, "__all__", ()):
             if name.startswith("_") or name.isupper() or name.islower():
@@ -323,6 +345,8 @@ def test_standalone_vocab_is_not_stale() -> None:
 
 
 def test_promoted_pairs_drift() -> None:
+    """Each promoted runtime constant holds exactly the values of the `Literal`
+    type it manifests, so the two cannot drift apart."""
     pairs = [
         (zm.ENDIANNESS, zm.Endianness),
         (zm.BLOSC_CNAME, zm.BloscCName),
@@ -331,7 +355,134 @@ def test_promoted_pairs_drift() -> None:
         (zm.NUMPY_TIME_UNIT, zm.NumpyTimeUnit),
         (zm.CAST_ROUNDING_MODE, zm.CastRoundingMode),
         (zm.CAST_OUT_OF_RANGE_MODE, zm.CastOutOfRangeMode),
-        (zm.ARRAY_ORDER_V2, zm.ZarrV2ArrayOrder),
+        (zm.ZARR_V2_ARRAY_ORDER, zm.ZarrV2ArrayOrder),
+        (zm.ZARR_V2_ARRAY_DIMENSION_SEPARATOR, zm.ZarrV2ArrayDimensionSeparator),
+        (zm.DEFAULT_CHUNK_KEY_ENCODING_SEPARATOR, zm.DefaultChunkKeyEncodingSeparator),
+        (zm.V2_CHUNK_KEY_ENCODING_SEPARATOR, zm.V2ChunkKeyEncodingSeparator),
     ]
     for const, lit in pairs:
         assert set(const) == set(get_args(lit))
+
+
+def constant_name_for(type_name: str) -> str:
+    """Derive a constant's name from the name of the type it manifests.
+
+    The transformation is purely syntactic: split at each lowercase-to-uppercase
+    boundary and before an uppercase run that starts a new word, then uppercase.
+    Digit runs stay glued to the token they follow (`Uint8` -> `UINT8`,
+    `Crc32c` -> `CRC32C`), because a digit boundary in CamelCase does not mark a
+    word boundary in the spec vocabulary these names model.
+
+    Consecutive capitals do not split, so acronym-adjacent names derive badly:
+    `ZarrV2ZArrayJSON` -> `ZARR_V2ZARRAY_JSON` and `...JSONPartial` ->
+    `...JSONPARTIAL`. Every such name in the package today is a `TypedDict` or
+    `TypeAliasType` that backs no constant, so none reaches this function — but
+    a future `Literal` spelled that way would silently be held to a bad name.
+    Splitting acronyms correctly needs a vocabulary, not a regex, so the rule
+    stays syntactic and this stays a known limit.
+    """
+    return re.sub(r"(?<=[a-z0-9])(?=[A-Z][a-z])|(?<=[a-z])(?=[A-Z])", "_", type_name).upper()
+
+
+def _literal_backed_constants() -> list[tuple[str, str, str]]:
+    """Every (module, constant, type) triple where a module-level SCREAMING_SNAKE
+    constant holds exactly the values of a `Literal` type in the same module.
+
+    Pairing is by value, not by proximity: a constant manifests the type whose
+    members it enumerates. Constants with no such type (extension-field keys,
+    key sets, canonical bit patterns) are exempt from the naming rule and are
+    simply absent from the result.
+    """
+    out: list[tuple[str, str, str]] = []
+    for module_name in _iter_module_names():
+        module = importlib.import_module(module_name)
+        literals = {
+            name: frozenset(get_args(obj))
+            for name, obj in vars(module).items()
+            if not name.startswith("_")
+            and not name.isupper()
+            and get_origin(obj) is Literal
+            and get_args(obj)
+        }
+        if not literals:
+            continue
+        for const_name, value in vars(module).items():
+            if const_name.startswith("_") or not const_name.isupper():
+                continue
+            members = frozenset(value) if isinstance(value, tuple) else frozenset({value})
+            if not all(isinstance(m, str) for m in members):
+                continue
+            matches = [t for t, args in literals.items() if args == members]
+            # A single unambiguous type means this constant manifests it. Ties
+            # (two Literals with identical members) carry no signal about which
+            # name the constant should take, so they are skipped.
+            if len(matches) == 1:
+                out.append((module_name, const_name, matches[0]))
+    return out
+
+
+def _value_tied_constants() -> set[str]:
+    """Constants whose manifested type is ambiguous because two or more `Literal`
+    types in the same module share its exact members.
+
+    These are invisible to the derivation check, so they are surfaced here and
+    counted, rather than silently dropped inside the pairing helper."""
+    tied: set[str] = set()
+    for module_name in _iter_module_names():
+        module = importlib.import_module(module_name)
+        literals = [
+            frozenset(get_args(obj))
+            for name, obj in vars(module).items()
+            if not name.startswith("_")
+            and not name.isupper()
+            and get_origin(obj) is Literal
+            and get_args(obj)
+        ]
+        for const_name, value in vars(module).items():
+            if const_name.startswith("_") or not const_name.isupper():
+                continue
+            members = frozenset(value) if isinstance(value, tuple) else frozenset({value})
+            if not all(isinstance(m, str) for m in members):
+                continue
+            if sum(1 for args in literals if args == members) > 1:
+                tied.add(f"{module_name}.{const_name}")
+    return tied
+
+
+# Constants whose `Literal` type cannot be identified by value because another
+# `Literal` in the same module has identical members. Pairing is by value, so a
+# tie carries no signal about which name the constant should take. These are
+# checked by eye; the count below fails if the tied set grows silently.
+KNOWN_VALUE_TIES = 9
+
+
+def test_constant_names_derive_from_their_type_names() -> None:
+    """Every `Literal`-backed constant whose type can be identified by value has
+    a name that is the mechanical transform of that type's name.
+
+    Constants tied to more than one identically-valued `Literal` are exempt (see
+    `KNOWN_VALUE_TIES`), as are constants in private modules and those backing
+    no `Literal` at all — so this pins the rule for most of the package, not all
+    of it."""
+    pairs = _literal_backed_constants()
+    assert pairs, "found no Literal-backed constants to check"
+    violations = [
+        f"{module}: {const} should be {constant_name_for(type_name)} (manifests {type_name})"
+        for module, const, type_name in pairs
+        if const != constant_name_for(type_name)
+    ]
+    assert not violations, "constants whose names do not derive from their type:\n" + "\n".join(
+        violations
+    )
+
+
+def test_value_tied_constants_are_a_known_set() -> None:
+    """The derivation check cannot see constants whose type is ambiguous by
+    value. Pin how many there are, so the exempt set cannot grow unnoticed and
+    quietly shrink the rule's coverage."""
+    tied = _value_tied_constants()
+    assert len(tied) == KNOWN_VALUE_TIES, (
+        f"value-tied constants changed (expected {KNOWN_VALUE_TIES}, got {len(tied)}); "
+        f"these are unchecked by the derivation rule and must be named by hand:\n"
+        + "\n".join(sorted(tied))
+    )