diff --git a/geotribu_cli/constants.py b/geotribu_cli/constants.py
index 5c9b188..414fda0 100644
--- a/geotribu_cli/constants.py
+++ b/geotribu_cli/constants.py
@@ -7,6 +7,7 @@
 # standard library
 import logging
 from dataclasses import dataclass
+from enum import Enum
 from pathlib import Path
 from typing import Literal
 
@@ -21,6 +22,59 @@
 # ################################
 
 
+class ExtendedEnum(Enum):
+    """Custom Enum with extended methods."""
+
+    @classmethod
+    def has_key(cls, name: str) -> bool:
+        """Check if a certain key is present in enum.
+
+        Source: https://stackoverflow.com/a/62065380/2556577
+
+        Args:
+            name (str): key to check.
+
+        Returns:
+            bool: True if the key exists.
+        """
+        return name in cls.__members__
+
+    @classmethod
+    def has_value(cls, value: str) -> bool:
+        """Check if a certain value is present in enum.
+
+        Source: https://stackoverflow.com/a/43634746/2556577
+
+        Args:
+            value (str): value to check
+
+        Returns:
+            bool: True is the value exists.
+        """
+        return value in cls._value2member_map_
+
+    @classmethod
+    def values_set(cls) -> set:
+        """Return a set of enum values.
+
+        Returns:
+            set of enum's unique values
+        """
+        return {item.value for item in cls}
+
+
+class YamlHeaderMandatoryKeys(ExtendedEnum):
+    """Clés obligatoires dans l'en-tête d'un contenu Geotribu."""
+
+    AUTHORS = "authors"
+    CATEGORIES = "categories"
+    DATE = "date"
+    DESCRIPTION = "description"
+    LICENSE = "license"
+    TAGS = "tags"
+    TITLE = "title"
+
+
 @dataclass
 class GeotribuDefaults:
     """Defaults settings for Geotribu."""
@@ -113,3 +167,7 @@ def site_git_source_base_url(
 if __name__ == "__main__":
     defaults = GeotribuDefaults()
     print(defaults.cdn_search_index_full_url)
+    print(YamlHeaderMandatoryKeys.TITLE.value)
+    print("title" in YamlHeaderMandatoryKeys.__members__)
+    print("title" in YamlHeaderMandatoryKeys._value2member_map_)
+    print({item.value for item in YamlHeaderMandatoryKeys})
diff --git a/geotribu_cli/content/header_check.py b/geotribu_cli/content/header_check.py
index cb8af9e..251b885 100644
--- a/geotribu_cli/content/header_check.py
+++ b/geotribu_cli/content/header_check.py
@@ -5,7 +5,7 @@
 
 import frontmatter
 
-from geotribu_cli.constants import GeotribuDefaults
+from geotribu_cli.constants import GeotribuDefaults, YamlHeaderMandatoryKeys
 from geotribu_cli.json.json_client import JsonFeedClient
 from geotribu_cli.utils.check_image_size import get_image_dimensions_by_url
 from geotribu_cli.utils.check_path import check_path
@@ -14,16 +14,6 @@
 logger = logging.getLogger(__name__)
 defaults_settings = GeotribuDefaults()
 
-MANDATORY_KEYS = [
-    "title",
-    "authors",
-    "categories",
-    "date",
-    "description",
-    "license",
-    "tags",
-]
-
 # ############################################################################
 # ########## CLI #################
 # ################################
@@ -137,13 +127,20 @@ def check_tags_order(tags: list[str]) -> bool:
     return True
 
 
-def check_mandatory_keys(
-    keys: list[str], mandatory: list[str] = MANDATORY_KEYS
-) -> tuple[bool, set[str]]:
+def check_missing_mandatory_keys(keys: list[str]) -> tuple[bool, set[str]]:
+    """Liste les clés de l'en-tête qui sont manquantes par rapport à celles requises.
+
+    Args:
+        keys: clés de l'en-tête à comparer
+
+    Returns:
+        un tuple à 2 valeurs composé d'un booléen indiquant s'il manque une clé
+            obligatoire et la liste des clés manquantes
+    """
     missing = set()
-    for mk in mandatory:
-        if mk not in keys:
-            missing.add(mk)
+    for mandatory_key in YamlHeaderMandatoryKeys.values_set():
+        if mandatory_key not in keys:
+            missing.add(mandatory_key)
     return len(missing) == 0, missing
 
 
@@ -227,9 +224,7 @@ def run(args: argparse.Namespace) -> None:
                 logger.info("Ordre alphabétique des tags ok")
 
             # check that mandatory keys are present
-            all_present, missing = check_mandatory_keys(
-                yaml_meta.keys(), MANDATORY_KEYS
-            )
+            all_present, missing = check_missing_mandatory_keys(yaml_meta.keys())
             if not all_present:
                 msg = f"Les clés suivantes ne sont pas présentes dans l'entête markdown : {','.join(missing)}"
                 logger.error(msg)
diff --git a/tests/test_yaml_header_check.py b/tests/test_yaml_header_check.py
index 7cb7ecb..794f5af 100644
--- a/tests/test_yaml_header_check.py
+++ b/tests/test_yaml_header_check.py
@@ -7,10 +7,11 @@
 from geotribu_cli.content.header_check import (
     check_author_md,
     check_existing_tags,
-    check_mandatory_keys,
+    check_missing_mandatory_keys,
     check_tags_order,
 )
 
+# -- GLOBALS
 TEAM_FOLDER = Path("tests/fixtures/team")
 
 
@@ -56,12 +57,14 @@ def test_future_tags_order(self):
         self.assertFalse(check_tags_order(self.future_yaml_meta["tags"]))
 
     def test_past_mandatory_keys(self):
-        all_present, missing = check_mandatory_keys(self.past_yaml_meta.keys())
+        all_present, missing = check_missing_mandatory_keys(self.past_yaml_meta.keys())
         self.assertTrue(all_present)
         self.assertEqual(len(missing), 0)
 
     def test_future_mandatory_keys(self):
-        all_present, missing = check_mandatory_keys(self.future_yaml_meta.keys())
+        all_present, missing = check_missing_mandatory_keys(
+            self.future_yaml_meta.keys()
+        )
         self.assertFalse(all_present)
         self.assertEqual(len(missing), 2)
         self.assertIn("license", missing)