diff --git a/src/main/app/API/Crud.php b/src/main/app/API/Crud.php
index 76b93876ebe..ae425c3bd04 100644
--- a/src/main/app/API/Crud.php
+++ b/src/main/app/API/Crud.php
@@ -72,13 +72,22 @@ public function __construct(
      *
      * @return object|null
      */
-    public function get(string $class, $id)
+    public function get(string $class, $id, string $idProp = 'id')
     {
-        if (!is_numeric($id) && property_exists($class, 'uuid')) {
-            return $this->om->getRepository($class)->findOneBy(['uuid' => $id]);
+        if ('id' === $idProp) {
+            if (!is_numeric($id) && property_exists($class, 'uuid')) {
+                return $this->om->getRepository($class)->findOneBy(['uuid' => $id]);
+            }
+
+            return $this->om->getRepository($class)->findOneBy(['id' => $id]);
+        }
+
+        $identifiers = $this->schema->getIdentifiers($class);
+        if (!in_array($idProp, $identifiers)) {
+            throw new \LogicException(sprintf('You can only get entities with an identifier property (identifiers: %s).', implode(', ', $identifiers)));
         }
 
-        return $this->om->getRepository($class)->findOneBy(['id' => $id]);
+        return $this->om->getRepository($class)->findOneBy([$idProp => $id]);
     }
 
     public function find(string $class, $data)
diff --git a/src/main/app/Controller/AbstractCrudController.php b/src/main/app/Controller/AbstractCrudController.php
index d19cc8465e4..6cb2482f7e8 100644
--- a/src/main/app/Controller/AbstractCrudController.php
+++ b/src/main/app/Controller/AbstractCrudController.php
@@ -99,7 +99,8 @@ public function findAction(Request $request, $class)
      * @ApiDoc(
      *     description="Finds an object class $class.",
      *     parameters={
-     *          {"name": "id", "type": {"string", "integer"}, "description": "The object id or uuid"}
+     *          {"name": "field", "type": "string", "description": "The name of the identifier we want to use (eg. id, slug)"},
+     *          {"name": "id", "type": {"string", "integer"}, "description": "The object identifier value"}
      *     },
      *     response={"$object"}
      * )
@@ -107,22 +108,18 @@ public function findAction(Request $request, $class)
      * @param string|int $id
      * @param string     $class
      */
-    public function getAction(Request $request, $id, $class): JsonResponse
+    public function getAction(string $field, $id, $class): JsonResponse
     {
-        $query = $request->query->all();
-        $object = $this->crud->get($class, $id);
+        $options = static::getOptions();
 
-        $options = $this->options['get'];
-        if (isset($query['options'])) {
-            $options = $query['options'];
-        }
+        $object = $this->crud->get($class, $id, $field);
 
         if (!$object) {
             throw new NotFoundHttpException(sprintf('No object found for id %s of class %s', $id.'', $class));
         }
 
         return new JsonResponse(
-            $this->serializer->serialize($object, $options ?? [])
+            $this->serializer->serialize($object, $options['get'] ?? [])
         );
     }
 
diff --git a/src/main/app/Routing/ApiLoader.php b/src/main/app/Routing/ApiLoader.php
index 12203d2c84f..99fa2c85914 100644
--- a/src/main/app/Routing/ApiLoader.php
+++ b/src/main/app/Routing/ApiLoader.php
@@ -13,16 +13,17 @@
 
 class ApiLoader extends Loader
 {
+    // Route format : [path, method, defaults]
     const DEFAULT_MAP = [
-      'create' => ['', 'POST'],
-      'deleteBulk' => ['', 'DELETE'],
-      'list' => ['', 'GET'],
-      'csv' => ['/csv', 'GET'],
-      'find' => ['/find', 'GET'],
-      'copyBulk' => ['/copy', 'GET'],
-      'update' => ['/{id}', 'PUT'],
-      'get' => ['/{id}', 'GET'],
-      'exist' => ['/exist/{field}/{value}', 'GET'],
+        'create' => ['', 'POST'],
+        'deleteBulk' => ['', 'DELETE'],
+        'list' => ['', 'GET'],
+        'csv' => ['/csv', 'GET'],
+        'find' => ['/find', 'GET'],
+        'copyBulk' => ['/copy', 'GET'],
+        'update' => ['/{id}', 'PUT'],
+        'get' => ['/{field}/{id}', 'GET', ['field' => 'id']],
+        'exist' => ['/exist/{field}/{value}', 'GET'],
     ];
 
     /** @var bool */
@@ -151,6 +152,9 @@ private function loadFromPath($path, RouteCollection $routes)
                             $route = new ApiRoute($pattern, $routeDefaults, []);
                             $route->setAction($name);
                             $route->setMethods([$options[1]]);
+                            if (isset($options[2])) {
+                                $route->addDefaults($options[2]);
+                            }
                             $requirements = $refClass->newInstanceWithoutConstructor()->getRequirements();
 
                             if (isset($requirements[$name])) {
diff --git a/src/main/community/Resources/modules/tools/community/user/store/actions.js b/src/main/community/Resources/modules/tools/community/user/store/actions.js
index f32f7966c83..93557dc65d9 100644
--- a/src/main/community/Resources/modules/tools/community/user/store/actions.js
+++ b/src/main/community/Resources/modules/tools/community/user/store/actions.js
@@ -38,7 +38,7 @@ actions.open = (username, reload = false) => (dispatch, getState) => {
 
   return dispatch({
     [API_REQUEST]: {
-      url: url(['apiv2_user_find'], {filters: {username: username}}),
+      url: ['apiv2_user_get', {field: 'username', id: username}],
       silent: true,
       success: (response, dispatch) => dispatch(formActions.resetForm(selectors.FORM_NAME, response, false))
     }
diff --git a/src/main/core/Controller/WorkspaceController.php b/src/main/core/Controller/WorkspaceController.php
index d7e5a325d12..e0f1fd00297 100644
--- a/src/main/core/Controller/WorkspaceController.php
+++ b/src/main/core/Controller/WorkspaceController.php
@@ -173,11 +173,7 @@ public function openAction(string $slug, ?User $user = null): JsonResponse
      * Opens a tool.
      *
      * @Route("/{id}/tool/{toolName}", name="claro_workspace_open_tool")
-     * @EXT\ParamConverter(
-     *      "workspace",
-     *      class="Claroline\CoreBundle\Entity\Workspace\Workspace",
-     *      options={"mapping": {"id": "uuid"}}
-     * )
+     * @EXT\ParamConverter("workspace", class="Claroline\CoreBundle\Entity\Workspace\Workspace", options={"mapping": {"id": "uuid"}})
      */
     public function openToolAction(Workspace $workspace, string $toolName): JsonResponse
     {
@@ -220,11 +216,7 @@ public function openToolAction(Workspace $workspace, string $toolName): JsonResp
      * Submit access code.
      *
      * @Route("/unlock/{id}", name="claro_workspace_unlock", methods={"POST"})
-     * @EXT\ParamConverter(
-     *     "workspace",
-     *     class="Claroline\CoreBundle\Entity\Workspace\Workspace",
-     *     options={"mapping": {"id": "uuid"}}
-     * )
+     * @EXT\ParamConverter("workspace", class="Claroline\CoreBundle\Entity\Workspace\Workspace", options={"mapping": {"id": "uuid"}})
      */
     public function unlockAction(Workspace $workspace, Request $request): JsonResponse
     {
diff --git a/src/plugin/claco-form/Controller/API/EntryController.php b/src/plugin/claco-form/Controller/API/EntryController.php
index a860673f07d..63207860abe 100644
--- a/src/plugin/claco-form/Controller/API/EntryController.php
+++ b/src/plugin/claco-form/Controller/API/EntryController.php
@@ -57,10 +57,10 @@ public function getName(): string
         return 'clacoformentry';
     }
 
-    public function getAction(Request $request, $id, $class): JsonResponse
+    public function getAction(string $field, $id, $class): JsonResponse
     {
         /** @var Entry $entry */
-        $entry = $this->crud->get($class, $id);
+        $entry = $this->crud->get($class, $id, $field);
         if (!$entry) {
             throw new NotFoundHttpException('Entry cannot be found');
         }
diff --git a/src/plugin/message/Controller/MessageController.php b/src/plugin/message/Controller/MessageController.php
index 85afc0581bf..784ff2a58d6 100644
--- a/src/plugin/message/Controller/MessageController.php
+++ b/src/plugin/message/Controller/MessageController.php
@@ -277,23 +277,19 @@ public function getRootAction($id): JsonResponse
         return new JsonResponse($this->serializer->serialize($root, [Options::IS_RECURSIVE]));
     }
 
-    public function getAction(Request $request, $id, $class): JsonResponse
+    public function getAction(string $field, $id, $class): JsonResponse
     {
         $currentUser = $this->tokenStorage->getToken()->getUser();
 
-        $query = $request->query->all();
         $object = $this->crud->get($class, $id);
         $um = $this->om->getRepository(UserMessage::class)->findOneBy(['message' => $object, 'user' => $currentUser]);
         $this->crud->replace($um, 'isRead', true);
-        $options = $this->options['get'];
 
-        if (isset($query['options'])) {
-            $options = $query['options'];
-        }
+        $options = static::getOptions();
 
         if ($object) {
             return new JsonResponse(
-                $this->serializer->serialize($object, $options)
+                $this->serializer->serialize($object, $options['get'] ?? [])
             );
         }