GPT wrote this

jsonSchema.jinja

{%- set schema_name = "MySchema" | pascal -%}
{%- set list_type = "List" %}
namespace {{ schema_name }}
{
    static class ExceptionMessages
    {
        public static readonly string ValueIsTooLow = "{0} value is too low. (min: {1})"; 
        public static readonly string ValueIsTooHigh = "{0} value is too high. (max: {1})";
        public static readonly string ValueIsTooLong = "{0} value is too long. (max length: {1})";
        public static readonly string ValueIsTooShort = "{0} value is too short. (min length: {1})";
        public static readonly string ValueIsTooBig = "{0} value is too big. (max: {1})";
        public static readonly string ValueIsTooSmall = "{0} value is too small. (min: {1})";
        public static readonly string ValueIsInvalid = "{0} value is invalid.";
        public static readonly string ValueIsRequired = "{0} value is required.";
        public static readonly string ValueIsNotUnique = "{0} value is not unique.";
        public static readonly string ValueIsNotAnEmail = "{0} value is not an email.";
        public static readonly string ValueIsNotAnUrl = "{0} value is not an URL.";
        public static readonly string ValueIsNotADate = "{0} value is not a date.";
        public static readonly string ValueIsNotADateTime = "{0} value is not a date time.";
        public static readonly string ValueIsNotATime = "{0} value is not a time.";
    }

    static class RegexPatterns
    {
        public static readonly string Email = @"^\S+@\S+$";
        public static readonly string Url = @"^(http:\/\/www\.|https:\/\/www\.|http:\/\/|https:\/\/)?[a-z0-9]+([\-\.]{1}[a-z0-9]+)*\.[a-z]{2,5}(:[0-9]{1,5})?(\/.*)?$";
        public static readonly string Date = @"^\d{4}-\d{2}-\d{2}$";
        public static readonly string DateTime = @"^\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}(\.\d+)?(([+-]\d{2}:\d{2})|Z)?$";
        public static readonly string Time = @"^\d{2}:\d{2}:\d{2}$";
    }
  
{% for typeName in schema.definitions -%}
    {%- set type = schema.definitions[typeName] -%}
    {%- if type.type == 'object' -%}
        {%- set baseType = None -%}
        {%- if type.allOf -%}
            {%- for allOfType in type.allOf -%}
                {%- if allOfType.ref -%}
                    {%- set baseType = allOfType.ref.replace("#/definitions/", "") -%}
                {%- endif -%}
            {%- endfor -%}
        {%- endif %}
    public class {{ typeName | pascal }}
    {
        {%- if baseType -%}
            : {{ baseType | pascal }}
        {%- endif %}
    {%- for propertyName, property in type.properties.items() -%}
        {%- set csharpType = "" -%}
        {%- if property.type == 'integer' -%}
            {%- if property.format == 'int32' -%}
                {%- set csharpType = "int" -%}
            {%- endif -%}
            {%- if property.format == 'int64' -%}
                {%- set csharpType = "long" -%}
            {%- endif -%}
        {%-elif property.type == 'number' -%}
            {%- if property.format == 'float' -%}
                {%- set csharpType = "float" -%}
            {%- endif -%}
            {%- if property.format == 'double' -%}
                {%- set csharpType = "double" -%}
            {%- endif -%}
            {%- if property.format == 'decimal' -%}
                {%- set csharpType = "decimal" -%}
            {%- endif -%}
        {%- elif property.type == 'string' -%}
            {%- if property.format == 'date-time' -%}
                {%- set csharpType = "DateTime" -%}
            {%- endif -%}
            {%- if property.format == 'email' -%}
                {%- set csharpType = "string" -%}
            {%- endif -%}
            {%- if property.format == 'uri' -%}
                {%- set csharpType = "Uri" -%}
            {%- endif -%}
            {%- if property.format == 'date' -%}
                {%- set csharpType = "DateTime" -%}
            {%- endif -%}
            {%- if property.format == 'time' -%}
                {%- set csharpType = "TimeSpan" -%}
            {%- endif -%}
            {%- if property.format == 'uuid' -%}
                {%- set csharpType = "Guid" -%}
            {%- endif -%}
            {%- if property.format == 'ipv4' -%}
                {%- set csharpType = "IPAddress" -%}
            {%- endif -%}
            {%- if property.format == 'ipv6' -%}
                {%- set csharpType = "IPAddress" -%}
            {%- endif -%}
            {%- if property.format == 'hostname' -%}
                {%- set csharpType = "string" -%}
            {%- endif -%}
            {%- if not property.format -%}
                {%- set csharpType = "string" -%}
            {%- endif -%}
        {%- elif property.type == 'array' -%}
            {%- if property.items.type == 'integer' -%}
                {%- if property.items.format == 'int32' -%}
                    {%- set csharpType = list_type+"<int>" -%}
                {%- endif -%}
                {%- if property.items.format == 'int64' -%}
                    {%- set csharpType = list_type+"<long>" -%}
                {%- endif -%}
            {%- endif -%}
            {%- if property.items.type == 'number' -%}
                {%- if property.items.format == 'float' -%}
                    {%- set csharpType = list_type+"<float>" -%}
                {%- endif -%}
                {%- if property.items.format == 'double' -%}
                    {%- set csharpType = list_type+"<double>" -%}
                {%- endif -%}
                {%- if property.items.format == 'decimal' -%}
                    {%- set csharpType = list_type+"<decimal>" -%}
                {%- endif -%}
            {%- endif -%}
            {%- if property.items.type == 'string' -%}
                {%- if property.items.format == 'date-time' -%}
                    {%- set csharpType = list_type+"<DateTime>" -%}
                {%- endif -%}
                {%- if property.items.format == 'email' -%}
                    {%- set csharpType = list_type+"<string>" -%}
                {%- endif -%}
                {%- if property.items.format == 'uri' -%}
                    {%- set csharpType = list_type+"<Uri>" -%}
                {%- endif -%}
                {%- if property.items.format == 'uuid' -%}
                    {%- set csharpType = list_type+"<Guid>" -%}
                {%- endif -%}
                {%- if property.items.format == 'ipv4' -%}
                    {%- set csharpType = list_type+"<IPAddress>" -%}
                {%- endif -%}
                {%- if property.items.format == 'ipv6' -%}
                    {%- set csharpType = list_type+"<IPAddress>" -%}
                {%- endif -%}
                {%- if property.items.format == 'hostname' -%}
                    {%- set csharpType = list_type+"<string>" -%}
                {%- endif -%}
                {%- if not property.items.format -%}
                    {%- set csharpType = list_type+"<string>" -%}
                {%- endif -%}
            {%- endif -%}
            {%- if property.items['$ref'] -%}
                {%- set ref = property.items['$ref'] -%}
                {%- set ref = ref.split('/')[-1] -%}
                {%- set csharpType = ref -%}
            {%- endif -%}
        {%- else -%}
           {%- set csharpType = "object" -%}
        {%- endif -%}
        
        {%- if not property.type and not property.items -%}
            {%- if property['$ref'] -%}
                {%- set ref = property['$ref'] -%}
                {%- set ref = ref.split('/')[-1] -%}
                {%- set csharpType = ref -%}
            {%- endif -%}
        {%- endif -%}

        {%- if property.enum -%}
        public enum {{ propertyName | pascal }}Enum
        {
            {%- for value in property.enum -%}
                {{ value | pascal }} = {{ loop.index - 1 }},
            {%- endfor -%}
        }

        private {{ propertyName | pascal }}Enum _{{ propertyName }} = {{ propertyName | pascal }}Enum.{{ property.enum[0] | pascal }};
        public {{ propertyName | pascal }}Enum {{ propertyName | pascal }}
        {
            get
            {
                return _{{ propertyName }};
            }
            set
            {
                if (!Enum.IsDefined(typeof({{ propertyName | pascal }}Enum), value))
                {
                    throw new ArgumentOutOfRangeException("{{ propertyName | pascal }}", ExceptionMessages.ValueIsInvalid);
                }
                _{{ propertyName }} = value;
            }
        }
        {%- else %}
        private {{ csharpType }} _{{ propertyName }} { get; set; }

        {% if property.description -%} 
        /// <description>{{property.description}}</description> 
        {%- endif %}
        [System.Text.Json.Serialization.JsonPropertyName("{{ propertyName }}")]
        public {{ csharpType }} {{ propertyName | pascal }}
        {
            get
            {
                return _{{ propertyName }};
            }
            set
            {
                {%- if property.minimum -%}
                if (value < {{ property.minimum }})
                {
                    throw new ArgumentOutOfRangeException("{{ propertyName | pascal }}", string.Format(ExceptionMessages.ValueIsTooSmall, value, {{ property.minimum }}));
                }
                {%- endif -%}
                {%- if property.exclusiveMinimum -%}
                if (value <= {{ property.exclusiveMinimum }})
                {
                    throw new ArgumentOutOfRangeException("{{ propertyName | pascal }}", string.Format(ExceptionMessages.ValueIsTooSmall, value, {{ property.exclusiveMinimum }}));
                }
                {%- endif -%}
                {%- if property.maximum -%}
                if (value > {{ property.maximum }})
                {
                    throw new ArgumentOutOfRangeException("{{ propertyName | pascal }}", string.Format(ExceptionMessages.ValueIsTooBig, value, {{ property.maximum }}));
                }
                {%- endif -%}
                {%- if property.exclusiveMaximum -%}
                if (value >= {{ property.exclusiveMaximum }})
                {
                    throw new ArgumentOutOfRangeException("{{ propertyName | pascal }}", string.Format(ExceptionMessages.ValueIsTooBig, value, {{ property.exclusiveMaximum }}));
                }
                {%- endif -%}
                    {%- if property.maxLength -%}
                if (value.ToString().Length > {{ property.maxLength }})
                {
                    throw new ArgumentOutOfRangeException("{{ propertyName | pascal }}", string.Format(ExceptionMessages.ValueIsTooLong, value, {{ property.maxLength }}));
                }
                {%- endif -%}
                {%- if property.minLength -%}
                if (value.ToString().Length < {{ property.minLength }})
                {
                    throw new ArgumentOutOfRangeException("{{ propertyName | pascal }}", string.Format(ExceptionMessages.ValueIsTooShort, value, {{ property.minLength }}));
                }
                {%- endif -%}
                {%- if property.pattern -%}
                if (!System.Text.RegularExpressions.Regex.IsMatch(value.ToString(), Patterns.{{ property.pattern | pascal }}))
                {
                    throw new ArgumentOutOfRangeException("{{ propertyName | pascal }}", ExceptionMessages.ValueIsInvalid);
                }
                {%- endif -%}
                {%- if property.format == "email" -%}
                if (!System.Text.RegularExpressions.Regex.IsMatch(System.Text.Json.JsonSerializer.ToJson(value), Patterns.Email, System.Text.RegularExpressions.RegexOptions.Singleline))
                {
                    throw new System.ArgumentException(ExceptionMessages.ValueIsNotAnEmail, "{{ propertyName | pascal }}");
                }
                {%- endif -%}
                {%- if property.format == "uri" -%}
                if (!System.Uri.IsWellFormedUriString(System.Text.Json.JsonSerializer.ToJson(value), System.UriKind.RelativeOrAbsolute))
                {
                    throw new System.ArgumentException(ExceptionMessages.ValueIsNotAnUrl, "{{ propertyName | pascal }}");
                }
                {%- endif -%}
                {%- if property.format == "date" -%}
                if (!System.DateTime.TryParseExact(System.Text.Json.JsonSerializer.ToJson(value), Formats.Date, System.Globalization.CultureInfo.InvariantCulture, System.Globalization.DateTimeStyles.RoundtripKind, out _))
                {
                    throw new System.ArgumentException(ExceptionMessages.ValueIsNotADate, "{{ propertyName | pascal }}");
                }
                {%- endif -%}
                {%- if property.format == "date-time" -%}
                if (!System.DateTime.TryParseExact(System.Text.Json.JsonSerializer.ToJson(value), Formats.DateTime, System.Globalization.CultureInfo.InvariantCulture, System.Globalization.DateTimeStyles.RoundtripKind, out _))
                {
                    throw new System.ArgumentException(ExceptionMessages.ValueIsNotADateTime, "{{ propertyName | pascal }}");
                }
                {%- endif -%}
                {%- if property.format == "time" -%}
                if (!System.DateTime.TryParseExact(System.Text.Json.JsonSerializer.ToJson(value), Formats.Time, System.Globalization.CultureInfo.InvariantCulture, System.Globalization.DateTimeStyles.RoundtripKind, out _))
                {
                    throw new System.ArgumentException(ExceptionMessages.ValueIsNotATime, "{{ propertyName | pascal }}");
                }
                {%- endif %}
                _{{ propertyName }} = value;
            }
        }    
        {% endif -%}
    {%- endfor -%}
    {% endif -%}
   }
{%- endfor %}
}