diff --git a/src/mock_vws/_flask_server/vwq.py b/src/mock_vws/_flask_server/vwq.py
index 79b8252a5..a87f48307 100644
--- a/src/mock_vws/_flask_server/vwq.py
+++ b/src/mock_vws/_flask_server/vwq.py
@@ -137,7 +137,7 @@ def query() -> Response:
 
     databases = get_all_cloud_databases()
     request_body = request.stream.read()
-    run_query_validators(
+    validated_query = run_query_validators(
         request_headers=dict(request.headers),
         request_body=request_body,
         request_method=request.method,
@@ -147,11 +147,7 @@ def query() -> Response:
     date = email.utils.formatdate(timeval=None, localtime=False, usegmt=True)
 
     response_text = get_query_match_response_text(
-        request_headers=dict(request.headers),
-        request_body=request_body,
-        request_method=request.method,
-        request_path=request.path,
-        databases=databases,
+        validated_query=validated_query,
         query_match_checker=query_match_checker,
     )
 
diff --git a/src/mock_vws/_query_tools.py b/src/mock_vws/_query_tools.py
index 2ab51244d..8601830f8 100644
--- a/src/mock_vws/_query_tools.py
+++ b/src/mock_vws/_query_tools.py
@@ -2,65 +2,39 @@
 
 import base64
 import uuid
-from collections.abc import Iterable, Mapping
 from typing import Any
 
 from beartype import beartype
 
 from mock_vws._base64_decoding import decode_base64
 from mock_vws._constants import ResultCodes, TargetStatuses
-from mock_vws._database_matchers import get_database_matching_client_keys
 from mock_vws._matching import matching_targets
 from mock_vws._mock_common import json_dump
-from mock_vws._query_validators.multipart import parse_multipart
-from mock_vws.database import CloudDatabase
+from mock_vws._query_validators import ValidatedQuery
 from mock_vws.image_matchers import ImageMatcher
 
 
 @beartype
 def get_query_match_response_text(
     *,
-    request_headers: Mapping[str, str],
-    request_body: bytes,
-    request_method: str,
-    request_path: str,
-    databases: Iterable[CloudDatabase],
+    validated_query: ValidatedQuery,
     query_match_checker: ImageMatcher,
 ) -> str:
     """
     Args:
-        request_path: The path of the request.
-        request_headers: The headers sent with the request.
-        request_body: The body of the request.
-        request_method: The HTTP method of the request.
-        databases: All Vuforia databases.
+        validated_query: The database and the parsed body which the query
+            validators resolved the request to.
         query_match_checker: A callable which takes two image values and
             returns a match score, or ``None`` if they do not match.
 
     Returns:
         The response text for a query endpoint request.
     """
-    fields, files = parse_multipart(
-        request_headers=request_headers,
-        request_body=request_body,
-    )
-
-    max_num_results = fields.get(key="max_num_results", default="1")
-    include_target_data = fields.get(
-        key="include_target_data",
-        default="top",
-    ).lower()
-
-    image_part = files["image"]
-    image_value = image_part.stream.read()
-
-    database = get_database_matching_client_keys(
-        request_headers=request_headers,
-        request_body=request_body,
-        request_method=request_method,
-        request_path=request_path,
-        databases=databases,
-    )
+    fields = validated_query.form.fields
+    max_num_results = fields.get("max_num_results", "1")
+    include_target_data = fields.get("include_target_data", "top").lower()
+    image_value = validated_query.form.files["image"]
+    database = validated_query.database
 
     matches_best_first = matching_targets(
         matcher=query_match_checker,
diff --git a/src/mock_vws/_query_validators/__init__.py b/src/mock_vws/_query_validators/__init__.py
index 454767494..043ba7be3 100644
--- a/src/mock_vws/_query_validators/__init__.py
+++ b/src/mock_vws/_query_validators/__init__.py
@@ -1,9 +1,14 @@
 """Input validators to use in the mock query API."""
 
 from collections.abc import Iterable, Mapping
+from dataclasses import dataclass
 
 from beartype import beartype
 
+from mock_vws._query_validators.multipart import (
+    MultipartForm,
+    parse_multipart,
+)
 from mock_vws.database import CloudDatabase
 
 from .accept_header_validators import validate_accept_header
@@ -38,6 +43,24 @@
 from .project_state_validators import validate_project_state
 
 
+@beartype
+@dataclass(frozen=True, kw_only=True)
+class ValidatedQuery:
+    """What the validators learn about a query request which passes them.
+
+    Args:
+        database: The database which the request's client keys belong to.
+        form: The parsed body of the request.
+
+    Attributes:
+        database: The database which the request's client keys belong to.
+        form: The parsed body of the request.
+    """
+
+    database: CloudDatabase
+    form: MultipartForm
+
+
 @beartype
 def run_query_validators(
     *,
@@ -46,15 +69,28 @@ def run_query_validators(
     request_body: bytes,
     request_method: str,
     databases: Iterable[CloudDatabase],
-) -> None:
+) -> ValidatedQuery:
     """Run all validators.
 
+    Vuforia reports one problem with a request even when the request has
+    more than one. Which problem it reports is decided by the order of the
+    validators here, so that order is the mock's record of Vuforia's error
+    precedence, verified against the real service.
+
+    The body is parsed once, after the ``Content-Type`` header which names
+    its boundary has been validated, and the parsed form is shared by every
+    validator which reads the body.
+
     Args:
         request_path: The path of the request.
         request_headers: The headers sent with the request.
         request_body: The body of the request.
         request_method: The HTTP method of the request.
         databases: All Vuforia databases.
+
+    Returns:
+        The database which the request's client keys belong to, and the
+        parsed body of the request.
     """
     validate_content_length_header_is_int(request_headers=request_headers)
     validate_content_length_header_not_too_large(
@@ -72,20 +108,14 @@ def run_query_validators(
         request_headers=request_headers,
         databases=databases,
     )
-    validate_authorization(
-        request_headers=request_headers,
-        request_body=request_body,
-        request_method=request_method,
-        request_path=request_path,
-        databases=databases,
-    )
-    validate_project_state(
+    database = validate_authorization(
         request_headers=request_headers,
         request_body=request_body,
         request_method=request_method,
         request_path=request_path,
         databases=databases,
     )
+    validate_project_state(database=database)
     validate_accept_header(request_headers=request_headers)
     validate_date_header_given(request_headers=request_headers)
     validate_date_format(request_headers=request_headers)
@@ -94,35 +124,16 @@ def run_query_validators(
         request_headers=request_headers,
         request_body=request_body,
     )
-    validate_extra_fields(
-        request_headers=request_headers,
-        request_body=request_body,
-    )
-    validate_image_field_given(
-        request_headers=request_headers,
-        request_body=request_body,
-    )
-    validate_image_is_image(
-        request_headers=request_headers,
-        request_body=request_body,
-    )
-    validate_image_format(
-        request_headers=request_headers,
-        request_body=request_body,
-    )
-    validate_image_dimensions(
-        request_headers=request_headers,
-        request_body=request_body,
-    )
-    validate_image_file_size(
-        request_headers=request_headers,
-        request_body=request_body,
-    )
-    validate_max_num_results(
-        request_headers=request_headers,
-        request_body=request_body,
-    )
-    validate_include_target_data(
+    form = parse_multipart(
         request_headers=request_headers,
         request_body=request_body,
     )
+    validate_extra_fields(form=form)
+    validate_image_field_given(form=form)
+    validate_image_is_image(form=form)
+    validate_image_format(form=form)
+    validate_image_dimensions(form=form)
+    validate_image_file_size(form=form)
+    validate_max_num_results(form=form)
+    validate_include_target_data(form=form)
+    return ValidatedQuery(database=database, form=form)
diff --git a/src/mock_vws/_query_validators/auth_validators.py b/src/mock_vws/_query_validators/auth_validators.py
index ddd4310ea..edce27080 100644
--- a/src/mock_vws/_query_validators/auth_validators.py
+++ b/src/mock_vws/_query_validators/auth_validators.py
@@ -115,7 +115,7 @@ def validate_authorization(
     request_body: bytes,
     request_method: str,
     databases: Iterable[CloudDatabase],
-) -> None:
+) -> CloudDatabase:
     """Validate the authorization header given to the query endpoint.
 
     Args:
@@ -125,12 +125,15 @@ def validate_authorization(
         request_method: The HTTP method of the request.
         databases: All Vuforia databases.
 
+    Returns:
+        The database which the request's client keys belong to.
+
     Raises:
         AuthenticationFailureError: The "Authorization" header is not as
             expected.
     """
     try:
-        get_database_matching_client_keys(
+        return get_database_matching_client_keys(
             request_headers=request_headers,
             request_body=request_body,
             request_method=request_method,
diff --git a/src/mock_vws/_query_validators/fields_validators.py b/src/mock_vws/_query_validators/fields_validators.py
index fd4830d79..610f3e6dd 100644
--- a/src/mock_vws/_query_validators/fields_validators.py
+++ b/src/mock_vws/_query_validators/fields_validators.py
@@ -1,38 +1,26 @@
 """Validators for the fields given."""
 
 import logging
-from collections.abc import Mapping
 
 from beartype import beartype
 
 from mock_vws._query_validators.exceptions import UnknownParametersError
-from mock_vws._query_validators.multipart import parse_multipart
+from mock_vws._query_validators.multipart import MultipartForm
 
 _LOGGER = logging.getLogger(name=__name__)
 
 
 @beartype
-def validate_extra_fields(
-    *,
-    request_headers: Mapping[str, str],
-    request_body: bytes,
-) -> None:
+def validate_extra_fields(*, form: MultipartForm) -> None:
     """Validate that the no unknown fields are given.
 
     Args:
-        request_headers: The headers sent with the request.
-        request_body: The body of the request.
+        form: The parsed body of the request.
 
     Raises:
         UnknownParametersError: Extra fields are given.
-        NoContentDispositionError: A part of the body has no
-            ``Content-Disposition`` header.
     """
-    fields, files = parse_multipart(
-        request_headers=request_headers,
-        request_body=request_body,
-    )
-    parsed_keys = fields.keys() | files.keys()
+    parsed_keys = form.fields.keys() | form.files.keys()
     known_parameters = {"image", "max_num_results", "include_target_data"}
 
     if not parsed_keys - known_parameters:
diff --git a/src/mock_vws/_query_validators/image_validators.py b/src/mock_vws/_query_validators/image_validators.py
index f3d1926fd..19a8f7e7e 100644
--- a/src/mock_vws/_query_validators/image_validators.py
+++ b/src/mock_vws/_query_validators/image_validators.py
@@ -2,10 +2,8 @@
 
 import io
 import logging
-from collections.abc import Mapping
 
 from beartype import beartype
-from werkzeug.datastructures import FileStorage, MultiDict
 
 from mock_vws._image_opening import open_image
 from mock_vws._query_validators.exceptions import (
@@ -13,53 +11,22 @@
     ImageNotGivenError,
     RequestEntityTooLargeError,
 )
-from mock_vws._query_validators.multipart import parse_multipart
+from mock_vws._query_validators.multipart import MultipartForm
 
 _LOGGER = logging.getLogger(name=__name__)
 
 
 @beartype
-def _parse_multipart_files(
-    *,
-    request_headers: Mapping[str, str],
-    request_body: bytes,
-) -> MultiDict[str, FileStorage]:
-    """Parse the multipart body and return the files section.
-
-    Args:
-        request_headers: The headers sent with the request.
-        request_body: The body of the request.
-
-    Returns:
-        The files parsed from the multipart body.
-    """
-    _, files = parse_multipart(
-        request_headers=request_headers,
-        request_body=request_body,
-    )
-    return files
-
-
-@beartype
-def validate_image_field_given(
-    *,
-    request_headers: Mapping[str, str],
-    request_body: bytes,
-) -> None:
+def validate_image_field_given(*, form: MultipartForm) -> None:
     """Validate that the image field is given.
 
     Args:
-        request_headers: The headers sent with the request.
-        request_body: The body of the request.
+        form: The parsed body of the request.
 
     Raises:
         ImageNotGivenError: The image field is not given.
     """
-    files = _parse_multipart_files(
-        request_headers=request_headers,
-        request_body=request_body,
-    )
-    if files.get(key="image") is not None:
+    if "image" in form.files:
         return
 
     _LOGGER.warning(msg="The image field is not given.")
@@ -67,26 +34,16 @@ def validate_image_field_given(
 
 
 @beartype
-def validate_image_file_size(
-    *,
-    request_headers: Mapping[str, str],
-    request_body: bytes,
-) -> None:
+def validate_image_file_size(*, form: MultipartForm) -> None:
     """Validate the file size of the image given to the query endpoint.
 
     Args:
-        request_headers: The headers sent with the request.
-        request_body: The body of the request.
+        form: The parsed body of the request.
 
     Raises:
         RequestEntityTooLargeError: The image file size is too large.
     """
-    files = _parse_multipart_files(
-        request_headers=request_headers,
-        request_body=request_body,
-    )
-    image_part = files["image"]
-    image_value = image_part.stream.read()
+    image_value = form.files["image"]
 
     # This is the documented maximum size of a PNG as per.
     # https://developer.vuforia.com/library/web-api/vuforia-query-web-api.
@@ -102,28 +59,17 @@ def validate_image_file_size(
 
 
 @beartype
-def validate_image_dimensions(
-    *,
-    request_headers: Mapping[str, str],
-    request_body: bytes,
-) -> None:
+def validate_image_dimensions(*, form: MultipartForm) -> None:
     """Validate the dimensions the image given to the query endpoint.
 
     Args:
-        request_headers: The headers sent with the request.
-        request_body: The body of the request.
+        form: The parsed body of the request.
 
     Raises:
         BadImageError: The image is given and is not within the maximum width
             and height limits.
     """
-    files = _parse_multipart_files(
-        request_headers=request_headers,
-        request_body=request_body,
-    )
-    image_part = files["image"]
-    image_value = image_part.stream.read()
-    image_file = io.BytesIO(initial_bytes=image_value)
+    image_file = io.BytesIO(initial_bytes=form.files["image"])
     with open_image(fp=image_file) as pil_image:
         max_width = 30000
         max_height = 30000
@@ -135,26 +81,17 @@ def validate_image_dimensions(
 
 
 @beartype
-def validate_image_format(
-    *,
-    request_headers: Mapping[str, str],
-    request_body: bytes,
-) -> None:
+def validate_image_format(*, form: MultipartForm) -> None:
     """Validate the format of the image given to the query endpoint.
 
     Args:
-        request_headers: The headers sent with the request.
-        request_body: The body of the request.
+        form: The parsed body of the request.
 
     Raises:
         BadImageError: The image is given and is not either a PNG or a JPEG.
     """
-    files = _parse_multipart_files(
-        request_headers=request_headers,
-        request_body=request_body,
-    )
-    image_part = files["image"]
-    with open_image(fp=image_part.stream) as pil_image:
+    image_file = io.BytesIO(initial_bytes=form.files["image"])
+    with open_image(fp=image_file) as pil_image:
         if pil_image.format in {"PNG", "JPEG"}:
             return
 
@@ -163,25 +100,16 @@ def validate_image_format(
 
 
 @beartype
-def validate_image_is_image(
-    *,
-    request_headers: Mapping[str, str],
-    request_body: bytes,
-) -> None:
+def validate_image_is_image(*, form: MultipartForm) -> None:
     """Validate that the given image data is actually an image file.
 
     Args:
-        request_headers: The headers sent with the request.
-        request_body: The body of the request.
+        form: The parsed body of the request.
 
     Raises:
         BadImageError: Image data is given and it is not an image file.
     """
-    files = _parse_multipart_files(
-        request_headers=request_headers,
-        request_body=request_body,
-    )
-    image_file = files["image"].stream
+    image_file = io.BytesIO(initial_bytes=form.files["image"])
 
     try:
         with open_image(fp=image_file) as _:
diff --git a/src/mock_vws/_query_validators/include_target_data_validators.py b/src/mock_vws/_query_validators/include_target_data_validators.py
index 89396b8e5..75e6debe4 100644
--- a/src/mock_vws/_query_validators/include_target_data_validators.py
+++ b/src/mock_vws/_query_validators/include_target_data_validators.py
@@ -1,39 +1,29 @@
 """Validators for the ``include_target_data`` field."""
 
 import logging
-from collections.abc import Mapping
 
 from beartype import beartype
 
 from mock_vws._query_validators.exceptions import InvalidIncludeTargetDataError
-from mock_vws._query_validators.multipart import parse_multipart
+from mock_vws._query_validators.multipart import MultipartForm
 
 _LOGGER = logging.getLogger(name=__name__)
 
 
 @beartype
-def validate_include_target_data(
-    *,
-    request_headers: Mapping[str, str],
-    request_body: bytes,
-) -> None:
+def validate_include_target_data(*, form: MultipartForm) -> None:
     """Validate the ``include_target_data`` field is either an accepted
     value
     or not given.
 
     Args:
-        request_headers: The headers sent with the request.
-        request_body: The body of the request.
+        form: The parsed body of the request.
 
     Raises:
         InvalidIncludeTargetDataError: The ``include_target_data`` field is not
             an accepted value.
     """
-    fields, _ = parse_multipart(
-        request_headers=request_headers,
-        request_body=request_body,
-    )
-    include_target_data = fields.get(key="include_target_data", default="top")
+    include_target_data = form.fields.get("include_target_data", "top")
     allowed_included_target_data = {"top", "all", "none"}
     if include_target_data.lower() in allowed_included_target_data:
         return
diff --git a/src/mock_vws/_query_validators/multipart.py b/src/mock_vws/_query_validators/multipart.py
index a6c5c6702..8ab774816 100644
--- a/src/mock_vws/_query_validators/multipart.py
+++ b/src/mock_vws/_query_validators/multipart.py
@@ -5,6 +5,7 @@
 import io
 import logging
 from collections.abc import Mapping
+from dataclasses import dataclass
 from email.message import EmailMessage
 
 from beartype import beartype
@@ -16,6 +17,27 @@
 _LOGGER = logging.getLogger(name=__name__)
 
 
+@beartype
+@dataclass(frozen=True, kw_only=True)
+class MultipartForm:
+    """The parsed ``multipart/form-data`` body of a query request.
+
+    Where the body gives a field more than once, the first value is kept, as
+    it is by every reader of the raw parse.
+
+    Args:
+        fields: The form fields, by name.
+        files: The content of each file part, by name.
+
+    Attributes:
+        fields: The form fields, by name.
+        files: The content of each file part, by name.
+    """
+
+    fields: Mapping[str, str]
+    files: Mapping[str, bytes]
+
+
 @beartype
 def _parse_with_boundary(
     *,
@@ -47,7 +69,7 @@ def parse_multipart(
     *,
     request_headers: Mapping[str, str],
     request_body: bytes,
-) -> tuple[MultiDict[str, str], MultiDict[str, FileStorage]]:
+) -> MultipartForm:
     """Parse the multipart body of a query request.
 
     Vuforia accepts a body which ends before its closing boundary, as a
@@ -60,7 +82,7 @@ def parse_multipart(
         request_body: The body of the request.
 
     Returns:
-        The fields and the files parsed from the multipart body.
+        The form parsed from the multipart body.
 
     Raises:
         NoContentDispositionError: The body ends within the headers of a part,
@@ -95,12 +117,19 @@ def parse_multipart(
 
     for candidate in candidates:
         try:
-            return _parse_with_boundary(
+            fields, files = _parse_with_boundary(
                 request_body=candidate,
                 boundary=boundary,
             )
         except ValueError:
             continue
+        return MultipartForm(
+            fields=fields.to_dict(),
+            files={
+                name: file_storage.stream.read()
+                for name, file_storage in files.items()
+            },
+        )
 
     # Every remaining body is one in which a part has no usable
     # ``Content-Disposition`` header, either because the body ends before that
diff --git a/src/mock_vws/_query_validators/num_results_validators.py b/src/mock_vws/_query_validators/num_results_validators.py
index 7d1f8962f..1197b7f9f 100644
--- a/src/mock_vws/_query_validators/num_results_validators.py
+++ b/src/mock_vws/_query_validators/num_results_validators.py
@@ -1,7 +1,6 @@
 """Validators for the ``max_num_results`` fields."""
 
 import logging
-from collections.abc import Mapping
 
 from beartype import beartype
 
@@ -9,24 +8,19 @@
     InvalidMaxNumResultsError,
     MaxNumResultsOutOfRangeError,
 )
-from mock_vws._query_validators.multipart import parse_multipart
+from mock_vws._query_validators.multipart import MultipartForm
 
 _LOGGER = logging.getLogger(name=__name__)
 
 
 @beartype
-def validate_max_num_results(
-    *,
-    request_headers: Mapping[str, str],
-    request_body: bytes,
-) -> None:
+def validate_max_num_results(*, form: MultipartForm) -> None:
     """Validate the ``max_num_results`` field is either an integer within
     range
     or not given.
 
     Args:
-        request_headers: The headers sent with the request.
-        request_body: The body of the request.
+        form: The parsed body of the request.
 
     Raises:
         InvalidMaxNumResultsError: The ``max_num_results`` given is not an
@@ -34,11 +28,7 @@ def validate_max_num_results(
         MaxNumResultsOutOfRangeError: The ``max_num_results`` given is not in
             range.
     """
-    fields, _ = parse_multipart(
-        request_headers=request_headers,
-        request_body=request_body,
-    )
-    max_num_results = fields.get(key="max_num_results", default="1")
+    max_num_results = form.fields.get("max_num_results", "1")
 
     try:
         max_num_results_int = int(max_num_results)
diff --git a/src/mock_vws/_query_validators/project_state_validators.py b/src/mock_vws/_query_validators/project_state_validators.py
index 7767499b2..4f6075826 100644
--- a/src/mock_vws/_query_validators/project_state_validators.py
+++ b/src/mock_vws/_query_validators/project_state_validators.py
@@ -1,11 +1,9 @@
 """Validators for the project state."""
 
 import logging
-from collections.abc import Iterable, Mapping
 
 from beartype import beartype
 
-from mock_vws._database_matchers import get_database_matching_client_keys
 from mock_vws._query_validators.exceptions import InactiveProjectError
 from mock_vws.database import CloudDatabase
 from mock_vws.states import States
@@ -14,34 +12,15 @@
 
 
 @beartype
-def validate_project_state(
-    *,
-    request_path: str,
-    request_headers: Mapping[str, str],
-    request_body: bytes,
-    request_method: str,
-    databases: Iterable[CloudDatabase],
-) -> None:
+def validate_project_state(*, database: CloudDatabase) -> None:
     """Validate the state of the project.
 
     Args:
-        request_path: The path of the request.
-        request_headers: The headers sent with the request.
-        request_body: The body of the request.
-        request_method: The HTTP method of the request.
-        databases: All Vuforia databases.
+        database: The database which the request's client keys belong to.
 
     Raises:
         InactiveProjectError: The project is inactive.
     """
-    database = get_database_matching_client_keys(
-        request_headers=request_headers,
-        request_body=request_body,
-        request_method=request_method,
-        request_path=request_path,
-        databases=databases,
-    )
-
     if database.state != States.PROJECT_INACTIVE:
         return
 
diff --git a/src/mock_vws/_requests_mock_server/mock_web_query_api.py b/src/mock_vws/_requests_mock_server/mock_web_query_api.py
index bdf7b67b9..9362f2bfb 100644
--- a/src/mock_vws/_requests_mock_server/mock_web_query_api.py
+++ b/src/mock_vws/_requests_mock_server/mock_web_query_api.py
@@ -117,7 +117,7 @@ def query(self, request: RequestData) -> _ResponseType:
             )
 
         try:
-            run_query_validators(
+            validated_query = run_query_validators(
                 request_path=request.path,
                 request_headers=request.headers,
                 request_body=request.body,
@@ -128,11 +128,7 @@ def query(self, request: RequestData) -> _ResponseType:
             return exc.status_code, exc.headers, exc.response_text
 
         response_text = get_query_match_response_text(
-            request_headers=request.headers,
-            request_body=request.body,
-            request_method=request.method,
-            request_path=request.path,
-            databases=self._target_manager.cloud_databases,
+            validated_query=validated_query,
             query_match_checker=self._query_match_checker,
         )
 
diff --git a/src/mock_vws/_services_validators/active_flag_validators.py b/src/mock_vws/_services_validators/active_flag_validators.py
index d2d8921a2..58eab5c40 100644
--- a/src/mock_vws/_services_validators/active_flag_validators.py
+++ b/src/mock_vws/_services_validators/active_flag_validators.py
@@ -1,6 +1,5 @@
 """Validators for the active flag."""
 
-import json
 import logging
 from http import HTTPStatus
 
@@ -23,7 +22,7 @@ def validate_active_flag(*, context: ValidatorContext) -> None:
         FailError: There is active flag data given to the endpoint which is not
             either a Boolean or NULL.
     """
-    request_json = json.loads(s=context.request_body.decode())
+    request_json = context.request_json
     if "active_flag" not in request_json:
         return
 
diff --git a/src/mock_vws/_services_validators/context.py b/src/mock_vws/_services_validators/context.py
index 9fbf5c7af..8f85bd760 100644
--- a/src/mock_vws/_services_validators/context.py
+++ b/src/mock_vws/_services_validators/context.py
@@ -1,16 +1,30 @@
 """The request context which every services validator is given."""
 
+import json
 from collections.abc import Mapping
 from dataclasses import dataclass
+from functools import cached_property
+from typing import Any, TypeIs
 
 from beartype import beartype
 
+from mock_vws._base64_decoding import decode_base64
 from mock_vws._database_matchers import AnyDatabase
 from mock_vws.request_rate_limits import RateLimitedEndpoint
 
 from .request_rate_limiter import RequestRateLimiter
 
 
+@beartype
+def _is_json_object(value: object, /) -> TypeIs[dict[str, Any]]:
+    """Return whether a decoded JSON value is an object.
+
+    JSON object keys are always strings, so a ``dict`` from ``json.loads``
+    is a ``dict[str, Any]``.
+    """
+    return isinstance(value, dict)
+
+
 @beartype
 @dataclass(frozen=True, kw_only=True)
 class ValidatorContext:
@@ -21,6 +35,10 @@ class ValidatorContext:
     copied onto the context rather than being looked up again from the
     path and the method.
 
+    The parsed forms of the body are computed the first time a validator
+    asks for them and then shared by every validator in the chain, so the
+    body is parsed once per request rather than once per validator.
+
     Args:
         request_path: The path of the request.
         request_headers: The headers sent with the request.
@@ -57,3 +75,42 @@ class ValidatorContext:
     optional_keys: frozenset[str]
     rate_limited_endpoint: RateLimitedEndpoint
     allowed_for_inactive_cloud_project: bool
+
+    @cached_property
+    def request_json(self) -> dict[str, Any]:
+        """The request body parsed as a JSON object.
+
+        A route's JSON validator runs before any validator which reads this,
+        so by the time a validator does read it, the body is known to be a
+        JSON object.
+
+        Raises:
+            ValueError: The body is not UTF-8 or is not JSON. Both
+                :py:class:`json.JSONDecodeError` and
+                :py:class:`UnicodeDecodeError` are kinds of this.
+            TypeError: The body is JSON but is not a JSON object.
+        """
+        parsed: object = json.loads(
+            s=self.request_body.decode(encoding="utf-8"),
+        )
+        if not _is_json_object(parsed):
+            msg = "The request body is not a JSON object."
+            raise TypeError(msg)
+        return parsed
+
+    @cached_property
+    def decoded_image(self) -> bytes | None:
+        """The base64 decoded image given in the request body, or ``None``
+        if no image was given.
+
+        The image data type and encoding validators run before any validator
+        which reads this, so by the time a validator does read it, the image
+        is known to be a base64 string.
+
+        Raises:
+            binascii.Error: The image cannot be base64 decoded.
+        """
+        image = self.request_json.get("image")
+        if image is None:
+            return None
+        return decode_base64(encoded_data=image)
diff --git a/src/mock_vws/_services_validators/image_validators.py b/src/mock_vws/_services_validators/image_validators.py
index b1e68ac4f..ee12cfafe 100644
--- a/src/mock_vws/_services_validators/image_validators.py
+++ b/src/mock_vws/_services_validators/image_validators.py
@@ -2,13 +2,11 @@
 
 import binascii
 import io
-import json
 import logging
 from http import HTTPStatus
 
 from beartype import beartype
 
-from mock_vws._base64_decoding import decode_base64
 from mock_vws._image_opening import open_image
 from mock_vws._services_validators.context import ValidatorContext
 from mock_vws._services_validators.exceptions import (
@@ -20,25 +18,6 @@
 _LOGGER = logging.getLogger(name=__name__)
 
 
-@beartype
-def _decoded_image(*, context: ValidatorContext) -> bytes | None:
-    """Return the base64 decoded image given in the request body.
-
-    Args:
-        context: The context of the request.
-
-    Returns:
-        The decoded image data, or ``None`` if no image was given. The data
-        has already been checked to be a decodable string by
-        :py:func:`validate_image_data_type` and
-        :py:func:`validate_image_encoding`.
-    """
-    image = json.loads(s=context.request_body.decode()).get("image")
-    if image is None:
-        return None
-    return decode_base64(encoded_data=image)
-
-
 @beartype
 def validate_image_data_type(*, context: ValidatorContext) -> None:
     """Validate that the given image data is a string.
@@ -49,7 +28,7 @@ def validate_image_data_type(*, context: ValidatorContext) -> None:
     Raises:
         FailError: Image data is given and it is not a string.
     """
-    request_json = json.loads(s=context.request_body.decode())
+    request_json = context.request_json
     if "image" not in request_json:
         return
 
@@ -72,12 +51,8 @@ def validate_image_encoding(*, context: ValidatorContext) -> None:
     Raises:
         FailError: Image data is given and it cannot be base64 decoded.
     """
-    request_json = json.loads(s=context.request_body.decode())
-    if "image" not in request_json:
-        return
-
     try:
-        decode_base64(encoded_data=request_json["image"])
+        _ = context.decoded_image
     except binascii.Error as exc:
         _LOGGER.warning('Image data cannot be base64 decoded: "%s"', exc)
         raise FailError(status_code=HTTPStatus.UNPROCESSABLE_ENTITY) from exc
@@ -93,7 +68,7 @@ def validate_image_is_image(*, context: ValidatorContext) -> None:
     Raises:
         BadImageError: Image data is given and it is not an image file.
     """
-    decoded = _decoded_image(context=context)
+    decoded = context.decoded_image
     if decoded is None:
         return
 
@@ -117,7 +92,7 @@ def validate_image_format(*, context: ValidatorContext) -> None:
     Raises:
         BadImageError:  The image is given and is not either a PNG or a JPEG.
     """
-    decoded = _decoded_image(context=context)
+    decoded = context.decoded_image
     if decoded is None:
         return
 
@@ -141,7 +116,7 @@ def validate_image_color_space(*, context: ValidatorContext) -> None:
         BadImageError: The image is given and is not in either the RGB or
             greyscale color space.
     """
-    decoded = _decoded_image(context=context)
+    decoded = context.decoded_image
     if decoded is None:
         return
 
@@ -167,7 +142,7 @@ def validate_image_size(*, context: ValidatorContext) -> None:
         ImageTooLargeError:  The image is given and is not under a certain file
             size threshold.
     """
-    decoded = _decoded_image(context=context)
+    decoded = context.decoded_image
     if decoded is None:
         return
 
@@ -193,7 +168,7 @@ def validate_image_pixel_count(*, context: ValidatorContext) -> None:
         ImageTooLargeError: The image is given and it has more than the
             maximum number of pixels.
     """
-    decoded = _decoded_image(context=context)
+    decoded = context.decoded_image
     if decoded is None:
         return
 
@@ -221,7 +196,7 @@ def validate_image_integrity(*, context: ValidatorContext) -> None:
     Raises:
         BadImageError: The image is given and is not a valid image file.
     """
-    decoded = _decoded_image(context=context)
+    decoded = context.decoded_image
     if decoded is None:
         return
 
diff --git a/src/mock_vws/_services_validators/instance_id_validators.py b/src/mock_vws/_services_validators/instance_id_validators.py
index 42b1ea0e9..7c70b8a65 100644
--- a/src/mock_vws/_services_validators/instance_id_validators.py
+++ b/src/mock_vws/_services_validators/instance_id_validators.py
@@ -1,6 +1,5 @@
 """Validators for VuMark instance IDs."""
 
-import json
 import logging
 
 from beartype import beartype
@@ -26,7 +25,7 @@ def validate_instance_id_type(*, context: ValidatorContext) -> None:
         BadRequestError: There is instance_id data given to the endpoint
             which is not a string.
     """
-    instance_id = json.loads(s=context.request_body.decode())["instance_id"]
+    instance_id = context.request_json["instance_id"]
 
     if isinstance(instance_id, str):
         return
@@ -49,7 +48,7 @@ def validate_instance_id_not_empty(*, context: ValidatorContext) -> None:
         InvalidInstanceIdError: There is instance_id data given to the
             endpoint which is an empty string.
     """
-    instance_id = json.loads(s=context.request_body.decode())["instance_id"]
+    instance_id = context.request_json["instance_id"]
 
     if instance_id:
         return
diff --git a/src/mock_vws/_services_validators/json_validators.py b/src/mock_vws/_services_validators/json_validators.py
index 0dcd7a889..57ccafb70 100644
--- a/src/mock_vws/_services_validators/json_validators.py
+++ b/src/mock_vws/_services_validators/json_validators.py
@@ -1,10 +1,8 @@
 """Validators for given JSON."""
 
-import json
 import logging
 from collections.abc import Callable
 from http import HTTPStatus
-from json.decoder import JSONDecodeError
 
 from beartype import beartype
 
@@ -66,20 +64,14 @@ def _validate_json(
         _LOGGER.warning(msg="The request body is empty.")
         raise make_empty_body_error()
 
+    # Vuforia gives the same response for a body which is not UTF-8, such as
+    # JSON encoded as latin-1, as it gives for a body which is not valid JSON
+    # or which is not a JSON object.
     try:
-        # Vuforia gives the same response for a body which is not UTF-8, such
-        # as JSON encoded as latin-1, as it gives for a body which is not
-        # valid JSON.
-        request_json = json.loads(
-            s=context.request_body.decode(encoding="utf-8"),
-        )
-    except (JSONDecodeError, UnicodeDecodeError) as exc:
-        _LOGGER.warning(msg="The request body is not valid JSON.")
-        raise make_invalid_json_error() from exc
-
-    if not isinstance(request_json, dict):
+        _ = context.request_json
+    except (TypeError, ValueError) as exc:
         _LOGGER.warning(msg="The request body is not a JSON object.")
-        raise make_invalid_json_error()
+        raise make_invalid_json_error() from exc
 
 
 @beartype
diff --git a/src/mock_vws/_services_validators/key_validators.py b/src/mock_vws/_services_validators/key_validators.py
index 84b7adff4..2372eea27 100644
--- a/src/mock_vws/_services_validators/key_validators.py
+++ b/src/mock_vws/_services_validators/key_validators.py
@@ -1,6 +1,5 @@
 """Validators for JSON keys."""
 
-import json
 import logging
 from http import HTTPStatus
 
@@ -25,7 +24,7 @@ def validate_keys(*, context: ValidatorContext) -> None:
             missing.
     """
     allowed_keys = context.mandatory_keys | context.optional_keys
-    request_json = json.loads(s=context.request_body.decode())
+    request_json = context.request_json
     given_keys = set(request_json.keys())
     all_given_keys_allowed = given_keys.issubset(allowed_keys)
     all_mandatory_keys_given = context.mandatory_keys.issubset(given_keys)
diff --git a/src/mock_vws/_services_validators/metadata_validators.py b/src/mock_vws/_services_validators/metadata_validators.py
index ce9d42c69..fcef39644 100644
--- a/src/mock_vws/_services_validators/metadata_validators.py
+++ b/src/mock_vws/_services_validators/metadata_validators.py
@@ -1,7 +1,6 @@
 """Validators for application metadata."""
 
 import binascii
-import json
 import logging
 from http import HTTPStatus
 
@@ -30,7 +29,7 @@ def validate_metadata_size(*, context: ValidatorContext) -> None:
         MetadataTooLargeError: Application metadata is given and it is too
             large.
     """
-    request_json = json.loads(s=context.request_body.decode())
+    request_json = context.request_json
     application_metadata = request_json.get("application_metadata")
     if application_metadata is None:
         return
@@ -55,7 +54,7 @@ def validate_metadata_encoding(*, context: ValidatorContext) -> None:
         FailError: Application metadata is given and it cannot be base64
             decoded.
     """
-    request_json = json.loads(s=context.request_body.decode())
+    request_json = context.request_json
     application_metadata = request_json.get("application_metadata")
 
     if application_metadata is None:
@@ -79,7 +78,7 @@ def validate_metadata_type(*, context: ValidatorContext) -> None:
         FailError: Application metadata is given and it is not a string or
             NULL.
     """
-    request_json = json.loads(s=context.request_body.decode())
+    request_json = context.request_json
     if "application_metadata" not in request_json:
         return
 
diff --git a/src/mock_vws/_services_validators/name_validators.py b/src/mock_vws/_services_validators/name_validators.py
index 377574f2f..bc49df600 100644
--- a/src/mock_vws/_services_validators/name_validators.py
+++ b/src/mock_vws/_services_validators/name_validators.py
@@ -1,6 +1,5 @@
 """Validators for target names."""
 
-import json
 import logging
 from http import HTTPStatus
 
@@ -33,7 +32,7 @@ def _given_name(*, context: ValidatorContext) -> str | None:
         The value has already been checked to be a string by
         :py:func:`validate_name_type`.
     """
-    request_json = json.loads(s=context.request_body.decode())
+    request_json = context.request_json
     name: str | None = request_json.get("name")
     return name
 
@@ -64,7 +63,7 @@ def _new_target_name(*, context: ValidatorContext) -> str:
         a request which does not give one, and :py:func:`validate_name_type`
         has already rejected one which is not a string.
     """
-    name: str = json.loads(s=context.request_body.decode())["name"]
+    name: str = context.request_json["name"]
     return name
 
 
@@ -141,7 +140,7 @@ def validate_name_type(*, context: ValidatorContext) -> None:
     Raises:
         FailError: A name is given and it is not a string.
     """
-    request_json = json.loads(s=context.request_body.decode())
+    request_json = context.request_json
     if "name" not in request_json:
         return
 
diff --git a/src/mock_vws/_services_validators/width_validators.py b/src/mock_vws/_services_validators/width_validators.py
index 01262d52f..fa5b7bbdc 100644
--- a/src/mock_vws/_services_validators/width_validators.py
+++ b/src/mock_vws/_services_validators/width_validators.py
@@ -1,6 +1,5 @@
 """Validators for the width field."""
 
-import json
 import logging
 from http import HTTPStatus
 
@@ -22,7 +21,7 @@ def validate_width(*, context: ValidatorContext) -> None:
     Raises:
         FailError: Width is given and is not a positive number.
     """
-    request_json = json.loads(s=context.request_body.decode())
+    request_json = context.request_json
     if "width" not in request_json:
         return