diff --git a/data_safe_haven/config/context_settings.py b/data_safe_haven/config/context_settings.py
index 795bfa1d72..10dab336c0 100644
--- a/data_safe_haven/config/context_settings.py
+++ b/data_safe_haven/config/context_settings.py
@@ -16,6 +16,11 @@
     DataSafeHavenParameterError,
 )
 from data_safe_haven.utility import LoggingSingleton, config_dir
+from data_safe_haven.utility.annotated_types import (
+    AzureLocation,
+    AzureLongName,
+    Guid,
+)
 
 
 def default_config_file_path() -> Path:
@@ -23,10 +28,10 @@ def default_config_file_path() -> Path:
 
 
 class Context(BaseModel):
-    admin_group_id: str
-    location: str
+    admin_group_id: Guid
+    location: AzureLocation
     name: str
-    subscription_name: str
+    subscription_name: AzureLongName
 
 
 class ContextSettings(BaseModel):
diff --git a/data_safe_haven/functions/__init__.py b/data_safe_haven/functions/__init__.py
index fcdb02ce72..6b444728ff 100644
--- a/data_safe_haven/functions/__init__.py
+++ b/data_safe_haven/functions/__init__.py
@@ -24,12 +24,7 @@
     validate_azure_vm_sku,
     validate_email_address,
     validate_ip_address,
-    validate_list,
-    validate_non_empty_list,
-    validate_non_empty_string,
-    validate_string_length,
     validate_timezone,
-    validate_type,
 )
 
 __all__ = [
@@ -54,10 +49,5 @@
     "validate_azure_vm_sku",
     "validate_email_address",
     "validate_ip_address",
-    "validate_list",
-    "validate_non_empty_list",
-    "validate_non_empty_string",
-    "validate_string_length",
     "validate_timezone",
-    "validate_type",
 ]
diff --git a/data_safe_haven/functions/validators.py b/data_safe_haven/functions/validators.py
index da41d3db24..a1526acd83 100644
--- a/data_safe_haven/functions/validators.py
+++ b/data_safe_haven/functions/validators.py
@@ -1,117 +1,50 @@
 import ipaddress
 import re
-from collections.abc import Callable
-from typing import Any
 
 import pytz
-import typer
 
 
-def validate_aad_guid(aad_guid: str | None) -> str | None:
-    if aad_guid is not None:
-        if not re.match(
-            r"^[a-z0-9]{8}-[a-z0-9]{4}-[a-z0-9]{4}-[a-z0-9]{4}-[a-z0-9]{12}$",
-            aad_guid,
-        ):
-            msg = "Expected GUID, for example '10de18e7-b238-6f1e-a4ad-772708929203'."
-            raise typer.BadParameter(msg)
+def validate_aad_guid(aad_guid: str) -> str:
+    if not re.match(
+        r"^[a-z0-9]{8}-[a-z0-9]{4}-[a-z0-9]{4}-[a-z0-9]{4}-[a-z0-9]{12}$",
+        aad_guid,
+    ):
+        msg = "Expected GUID, for example '10de18e7-b238-6f1e-a4ad-772708929203'."
+        raise ValueError(msg)
     return aad_guid
 
 
-def validate_azure_location(azure_location: str | None) -> str | None:
-    if azure_location is not None:
-        if not re.match(r"^[a-z]+[0-9]?[a-z]*$", azure_location):
-            msg = "Expected valid Azure location, for example 'uksouth'."
-            raise typer.BadParameter(msg)
+def validate_azure_location(azure_location: str) -> str:
+    if not re.match(r"^[a-z]+[0-9]?[a-z]*$", azure_location):
+        msg = "Expected valid Azure location, for example 'uksouth'."
+        raise ValueError(msg)
     return azure_location
 
 
-def validate_azure_vm_sku(azure_vm_sku: str | None) -> str | None:
-    if azure_vm_sku is not None:
-        if not re.match(r"^(Standard|Basic)_\w+$", azure_vm_sku):
-            msg = "Expected valid Azure VM SKU, for example 'Standard_D2s_v4'."
-            raise typer.BadParameter(msg)
+def validate_azure_vm_sku(azure_vm_sku: str) -> str:
+    if not re.match(r"^(Standard|Basic)_\w+$", azure_vm_sku):
+        msg = "Expected valid Azure VM SKU, for example 'Standard_D2s_v4'."
+        raise ValueError(msg)
     return azure_vm_sku
 
 
-def validate_email_address(email_address: str | None) -> str | None:
-    if email_address is not None:
-        if not re.match(r"^\S+@\S+$", email_address):
-            msg = "Expected valid email address, for example 'sherlock@holmes.com'."
-            raise typer.BadParameter(msg)
+def validate_email_address(email_address: str) -> str:
+    if not re.match(r"^\S+@\S+$", email_address):
+        msg = "Expected valid email address, for example 'sherlock@holmes.com'."
+        raise ValueError(msg)
     return email_address
 
 
-def validate_ip_address(
-    ip_address: str | None,
-) -> str | None:
+def validate_ip_address(ip_address: str) -> str:
     try:
-        if ip_address:
-            return str(ipaddress.ip_network(ip_address))
-        return None
+        return str(ipaddress.ip_network(ip_address))
     except Exception as exc:
         msg = "Expected valid IPv4 address, for example '1.1.1.1'."
-        raise typer.BadParameter(msg) from exc
+        raise ValueError(msg) from exc
 
 
-def validate_list(
-    value: list[Any],
-    validator: Callable[[Any], Any] | None = None,
-    *,
-    allow_empty: bool = False,
-) -> list[Any]:
-    try:
-        if not allow_empty:
-            validate_non_empty_list(value)
-        if validator:
-            for element in value:
-                validator(element)
-        return value
-    except Exception as exc:
-        msg = f"Expected valid list.\n{exc}"
-        raise typer.BadParameter(msg) from exc
-
-
-def validate_non_empty_list(value: list[Any]) -> list[Any]:
-    if len(value) == 0:
-        msg = "Expected non-empty list."
-        raise typer.BadParameter(msg)
-    return value
-
-
-def validate_non_empty_string(value: Any) -> str:
-    try:
-        return validate_string_length(value, min_length=1)
-    except Exception as exc:
-        msg = "Expected non-empty string."
-        raise typer.BadParameter(msg) from exc
-
-
-def validate_string_length(
-    value: Any, min_length: int | None = None, max_length: int | None = None
-) -> str:
-    if isinstance(value, str):
-        if min_length and len(value) < min_length:
-            msg = f"Expected string with minimum length {min_length}."
-            raise typer.BadParameter(msg)
-        if max_length and len(value) > max_length:
-            msg = f"Expected string with maximum length {max_length}."
-            raise typer.BadParameter(msg)
-        return str(value)
-    msg = "Expected string."
-    raise typer.BadParameter(msg)
-
-
-def validate_timezone(timezone: str | None) -> str | None:
-    if timezone is not None:
-        if timezone not in pytz.all_timezones:
-            msg = "Expected valid timezone, for example 'Europe/London'."
-            raise typer.BadParameter(msg)
+def validate_timezone(timezone: str) -> str:
+    if timezone not in pytz.all_timezones:
+        msg = "Expected valid timezone, for example 'Europe/London'."
+        raise ValueError(msg)
     return timezone
-
-
-def validate_type(value: Any, type_: type) -> Any:
-    if not isinstance(value, type_):
-        msg = f"Expected type '{type_.__name__}' but received '{type(value).__name__}'."
-        raise typer.BadParameter(msg)
-    return value
diff --git a/data_safe_haven/utility/annotated_types.py b/data_safe_haven/utility/annotated_types.py
new file mode 100644
index 0000000000..1db246dabf
--- /dev/null
+++ b/data_safe_haven/utility/annotated_types.py
@@ -0,0 +1,22 @@
+from typing import Annotated
+
+from pydantic import Field
+from pydantic.functional_validators import AfterValidator
+
+from data_safe_haven.functions import (
+    validate_aad_guid,
+    validate_azure_location,
+    validate_azure_vm_sku,
+    validate_email_address,
+    validate_ip_address,
+    validate_timezone,
+)
+
+AzureShortName = Annotated[str, Field(min_length=1, max_length=24)]
+AzureLongName = Annotated[str, Field(min_length=1, max_length=64)]
+AzureLocation = Annotated[str, AfterValidator(validate_azure_location)]
+AzureVmSku = Annotated[str, AfterValidator(validate_azure_vm_sku)]
+EmailAdress = Annotated[str, AfterValidator(validate_email_address)]
+Guid = Annotated[str, AfterValidator(validate_aad_guid)]
+IpAddress = Annotated[str, AfterValidator(validate_ip_address)]
+TimeZone = Annotated[str, AfterValidator(validate_timezone)]
diff --git a/tests_/config/test_context_settings.py b/tests_/config/test_context_settings.py
index e1cc3cfac5..8f04ed3fc1 100644
--- a/tests_/config/test_context_settings.py
+++ b/tests_/config/test_context_settings.py
@@ -3,23 +3,46 @@
 
 import pytest
 import yaml
+from pydantic import ValidationError
 from pytest import fixture
 
 
+@fixture
+def context_dict():
+    return {
+        "admin_group_id": "d5c5c439-1115-4cb6-ab50-b8e547b6c8dd",
+        "location": "uksouth",
+        "name": "Acme Deployment",
+        "subscription_name": "Data Safe Haven (Acme)"
+    }
+
+
 class TestContext:
-    def test_constructor(self):
-        context_dict = {
-            "admin_group_id": "d5c5c439-1115-4cb6-ab50-b8e547b6c8dd",
-            "location": "uksouth",
-            "name": "Acme Deployment",
-            "subscription_name": "Data Safe Haven (Acme)"
-        }
+    def test_constructor(self, context_dict):
         context = Context(**context_dict)
         assert isinstance(context, Context)
         assert all([
             getattr(context, item) == context_dict[item] for item in context_dict.keys()
         ])
 
+    def test_invalid_guid(self, context_dict):
+        context_dict["admin_group_id"] = "not a guid"
+        with pytest.raises(ValidationError) as exc:
+            Context(**context_dict)
+            assert "Value error, Expected GUID, for example" in exc
+
+    def test_invalid_location(self, context_dict):
+        context_dict["location"] = "not_a_location"
+        with pytest.raises(ValidationError) as exc:
+            Context(**context_dict)
+            assert "Value error, Expected valid Azure location" in exc
+
+    def test_invalid_subscription_name(self, context_dict):
+        context_dict["subscription_name"] = "very "*12 + "long name"
+        with pytest.raises(ValidationError) as exc:
+            Context(**context_dict)
+            assert "String should have at most 64 characters" in exc
+
 
 @fixture
 def context_yaml():