diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 1bbdc67..52cedf4 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -1,6 +1,6 @@
 repos:
 - repo: https://github.com/pre-commit/pre-commit-hooks
-  rev: v4.3.0
+  rev: v5.0.0
   hooks:
   - id: no-commit-to-branch # prevent direct commits to the `main` branch
   - id: check-yaml
@@ -24,3 +24,10 @@ repos:
       types: [python]
       language: system
       pass_filenames: false
+    - id: Typecheck
+      name: Typecheck
+      entry: make
+      args: [typecheck]
+      types: [python]
+      language: system
+      pass_filenames: false
diff --git a/Makefile b/Makefile
index 9c49a64..5f7f05c 100644
--- a/Makefile
+++ b/Makefile
@@ -25,6 +25,10 @@ lint:
 	uv run ruff format --check
 	uv run ruff check
 
+.PHONY: typecheck  # Typecheck the code
+typecheck:
+	uv run mypy pydantic_extra_types
+
 .PHONY: test
 test:
 	uv run pytest
diff --git a/pydantic_extra_types/domain.py b/pydantic_extra_types/domain.py
index 1e44ebb..6640de6 100644
--- a/pydantic_extra_types/domain.py
+++ b/pydantic_extra_types/domain.py
@@ -54,4 +54,5 @@ def __get_pydantic_core_schema__(cls, source_type: Any, handler: GetCoreSchemaHa
     def __get_pydantic_json_schema__(
         cls, schema: core_schema.CoreSchema, handler: GetCoreSchemaHandler
     ) -> dict[str, Any]:
-        return handler(schema)
+        # Cast the return value to dict[str, Any]
+        return dict(handler(schema))
diff --git a/pydantic_extra_types/phone_numbers.py b/pydantic_extra_types/phone_numbers.py
index ca1ccb9..880446f 100644
--- a/pydantic_extra_types/phone_numbers.py
+++ b/pydantic_extra_types/phone_numbers.py
@@ -90,7 +90,7 @@ class PhoneNumberValidator:
         supported_regions (list[str]): The supported regions. If empty, all regions are supported (default).
 
     Returns:
-        str: The formatted phone number.
+        The formatted phone number.
 
     Example:
         MyNumberType = Annotated[
diff --git a/pydantic_extra_types/semantic_version.py b/pydantic_extra_types/semantic_version.py
index 1da3f83..8ffdfde 100644
--- a/pydantic_extra_types/semantic_version.py
+++ b/pydantic_extra_types/semantic_version.py
@@ -53,3 +53,7 @@ def __get_pydantic_json_schema__(
                 pattern=r'^(0|[1-9]\d*)\.(0|[1-9]\d*)\.(0|[1-9]\d*)(?:-((?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*)(?:\.(?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*))*))?(?:\+([0-9a-zA-Z-]+(?:\.[0-9a-zA-Z-]+)*))?$'
             )
         )
+
+    @classmethod
+    def validate_from_str(cls, value: str) -> 'SemanticVersion':
+        return cls.parse(value)