diff --git a/CHANGELOG.md b/CHANGELOG.md
index fa3bbf95..ba6b749e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+
+- New `disable_metadata_checks` parameter in `zimscraperlib.zim.creator.Creator` initializer, allowing to disable metadata check at startup (assuming the user will validate them on its own) #119
+
 ### Changed
 
 - Using openZIM Python bootstrap conventions (including hatch-openzim plugin) #120
@@ -16,6 +20,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Rework the VideoWebmLow preset for faster encoding and smaller file size (preset has been bumped to version 2)
 - When reencoding a video, ffmpeg now uses only 1 CPU thread by default (new arg to `reencode` allows to override this default value)
 
+## Fixed
+
+- Fixed type hints of `zimscraperlib.zim.Item` and subclasses, and `zimscraperlib.image.optimization:convert_image`
+
 ## [3.2.0] - 2023-12-16
 
 ### Added
diff --git a/src/zimscraperlib/zim/creator.py b/src/zimscraperlib/zim/creator.py
index 4e25d1de..37dc1714 100644
--- a/src/zimscraperlib/zim/creator.py
+++ b/src/zimscraperlib/zim/creator.py
@@ -97,7 +97,12 @@ class Creator(libzim.writer.Creator):
     a segmentation fault at garbage collection (on exit mostly).
 
     Meaning you should exit right after an exception in your code (during zim creation)
-    Use workaround_nocancel=False to disable the workaround."""
+    Use workaround_nocancel=False to disable the workaround.
+
+    By default, all metadata are validated for compliance with openZIM guidelines and
+    conventions. Set disable_metadata_checks=False to disable this validation (you can
+    still do checks manually with the validation methods or your own logic).
+    """
 
     def __init__(
         self,
@@ -106,6 +111,7 @@ def __init__(
         compression: Optional[str] = None,
         workaround_nocancel: Optional[bool] = True,  # noqa: FBT002
         ignore_duplicates: Optional[bool] = False,  # noqa: FBT002
+        disable_metadata_checks: bool = True,  # noqa: FBT001, FBT002
     ):
         super().__init__(filename=filename)
         self._metadata = {}
@@ -123,6 +129,7 @@ def __init__(
 
         self.workaround_nocancel = workaround_nocancel
         self.ignore_duplicates = ignore_duplicates
+        self.disable_metadata_checks = disable_metadata_checks
 
     def config_indexing(
         self, indexing: bool, language: Optional[str] = None  # noqa: FBT001
@@ -141,9 +148,10 @@ def start(self):
         if not all(self._metadata.get(key) for key in MANDATORY_ZIM_METADATA_KEYS):
             raise ValueError("Mandatory metadata are not all set.")
 
-        for name, value in self._metadata.items():
-            if value:
-                self.validate_metadata(name, value)
+        if self.disable_metadata_checks:
+            for name, value in self._metadata.items():
+                if value:
+                    self.validate_metadata(name, value)
 
         language = self._metadata.get("Language", "").split(",")
         if language[0] and not self.__indexing_configured:
@@ -187,7 +195,8 @@ def add_metadata(
         content: Union[str, bytes, datetime.date, datetime.datetime, Iterable[str]],
         mimetype: str = "text/plain;charset=UTF-8",
     ):
-        self.validate_metadata(name, content)
+        if self.disable_metadata_checks:
+            self.validate_metadata(name, content)
         if name == "Date" and isinstance(content, (datetime.date, datetime.datetime)):
             content = content.strftime("%Y-%m-%d").encode("UTF-8")
         if (
diff --git a/tests/zim/test_zim_creator.py b/tests/zim/test_zim_creator.py
index a8770c4b..dc4d4741 100644
--- a/tests/zim/test_zim_creator.py
+++ b/tests/zim/test_zim_creator.py
@@ -507,6 +507,12 @@ def test_check_metadata(tmp_path):
         Creator(tmp_path, "").config_dev_metadata(LongDescription="T" * 5000).start()
 
 
+def test_relax_metadata(tmp_path):
+    Creator(tmp_path, "", disable_metadata_checks=False).config_dev_metadata(
+        Description="T" * 90
+    ).start()
+
+
 @pytest.mark.parametrize(
     "tags",
     [