diff --git a/src/AnthropicClient/Utils/JsonSchemaGenerator.cs b/src/AnthropicClient/Utils/JsonSchemaGenerator.cs
index 95b3c13..61bebd0 100644
--- a/src/AnthropicClient/Utils/JsonSchemaGenerator.cs
+++ b/src/AnthropicClient/Utils/JsonSchemaGenerator.cs
@@ -1,6 +1,8 @@
 using System.Reflection;
+using System.Text.Json;
 using System.Text.Json.Nodes;
 
+using AnthropicClient.Json;
 using AnthropicClient.Models;
 
 namespace AnthropicClient.Utils;
@@ -11,19 +13,26 @@ static class JsonSchemaGenerator
   private const string PropertiesKey = "properties";
   private const string RequiredPropertiesKey = "required";
   private const string DescriptionKey = "description";
-  private const string Object = "object";
+  private const string DefinitionsKey = "definitions";
+  private const string RefKey = "$ref";
+  private const string ItemsKey = "items";
+  private const string EnumKey = "enum";
+  private const string FormatKey = "format";
+  private const string ObjectType = "object";
+  private const string StringType = "string";
+  private const string ArrayType = "array";
 
-  public static JsonNode GenerateInputSchema(AnthropicFunction function)
+  internal static JsonObject GenerateInputSchema(AnthropicFunction function)
   {
     var parameters = function.Method.GetParameters();
-    var schema = new JsonObject()
+    var inputSchema = new JsonObject()
     {
-      [TypeKey] = Object
+      [TypeKey] = ObjectType
     };
 
     if (parameters.Length is 0)
     {
-      return schema;
+      return inputSchema;
     }
 
     var properties = new JsonObject();
@@ -42,10 +51,10 @@ static class JsonSchemaGenerator
       var paramDescription = attribute?.Description ?? string.Empty;
       var paramRequired = attribute?.Required ?? !parameter.HasDefaultValue;
 
-      var paramObject = new JsonObject();
-      paramObject[DescriptionKey] = paramDescription;
+      var paramSchema = GenerateParameterTypeSchema(parameter.ParameterType, inputSchema);
+      paramSchema[DescriptionKey] = paramDescription;
       
-      properties[paramName] = paramObject;
+      properties[paramName] = paramSchema;
 
       if (paramRequired)
       {
@@ -53,8 +62,103 @@ static class JsonSchemaGenerator
       }
     }
 
-    schema[PropertiesKey] = properties;
-    schema[RequiredPropertiesKey] = requiredProperties;
-    return schema;
+    inputSchema[PropertiesKey] = properties;
+    inputSchema[RequiredPropertiesKey] = requiredProperties;
+    return inputSchema;
+  }
+
+  private static JsonObject GenerateParameterTypeSchema(Type type, JsonObject inputSchema)
+  {
+    var definitions = inputSchema[DefinitionsKey];
+
+    // Check if a definition for the type already exists
+    // If it does, return a reference to the definition
+    // no need to evaluate the type further
+    if (definitions is not null && definitions.AsObject().ContainsKey(type.FullName))
+    {
+      return new JsonObject()
+      {
+        [RefKey] = $"#/definitions/{type.FullName}"
+      };
+    }
+
+    var paramSchema = type switch
+    {
+      var t when t == typeof(string) || t == typeof(char) => new JsonObject() 
+      { 
+        [TypeKey] = StringType 
+      },
+      var t when 
+        t == typeof(int) ||  
+        t == typeof(uint) ||
+        t == typeof(long) ||
+        t == typeof(ulong) || 
+        t == typeof(short) ||
+        t == typeof(ushort) || 
+        t == typeof(byte) || 
+        t == typeof(sbyte) => new JsonObject() 
+      { 
+        [TypeKey] = "integer" 
+      },
+      var t when t == typeof(bool) => new JsonObject() 
+      { 
+        [TypeKey] = "boolean" 
+      },
+      var t when 
+        t == typeof(double) || 
+        t == typeof(float) || 
+        t == typeof(decimal) => new JsonObject() 
+      { 
+        [TypeKey] = "number" 
+      },
+      var t when t == typeof(DateTime) || t == typeof(DateTimeOffset) => new JsonObject() 
+      { 
+        [TypeKey] = StringType, 
+        [FormatKey] = "date-time" 
+      },
+      var t when t == typeof(Guid) => new JsonObject() 
+      { 
+        [TypeKey] = StringType, 
+        [FormatKey] = "uuid" 
+      },
+      var t when t.IsEnum => new JsonObject() 
+      { 
+        [TypeKey] = StringType, 
+        [EnumKey] = Enum.GetNames(t).Aggregate(
+          new JsonArray(), (acc, name) => 
+          {
+            acc.Add(name); 
+            return acc; 
+          }
+        )
+      },
+      var t when t.IsArray => new JsonObject() 
+      { 
+        [TypeKey] = ArrayType, 
+        [ItemsKey] = GenerateParameterTypeSchema(t.GetElementType()!, inputSchema)
+      },
+      var t when t.IsGenericType && t.GetGenericTypeDefinition() == typeof(List<>) => new JsonObject() 
+      { 
+        [TypeKey] = ArrayType, 
+        [ItemsKey] = GenerateParameterTypeSchema(t.GetGenericArguments()[0], inputSchema)
+      },
+      _ => GenerateTypeDefinitionSchema(type, inputSchema)
+    };
+
+    return paramSchema;
+  }
+
+  private static JsonObject GenerateTypeDefinitionSchema(Type type, JsonObject inputSchema)
+  {
+    var definitions = inputSchema[DefinitionsKey] ?? new JsonObject();
+    var typeSchema = new JsonObject();
+
+    // TODO: Implement schema generation for complex types
+
+    definitions[type.FullName] = typeSchema;
+    return new JsonObject()
+    {
+      [RefKey] = $"#/definitions/{type.FullName}"
+    };
   }
 }
\ No newline at end of file
diff --git a/tests/AnthropicClient.Tests/Unit/Utils/JsonSchemaGeneratorTestData.cs b/tests/AnthropicClient.Tests/Unit/Utils/JsonSchemaGeneratorTestData.cs
new file mode 100644
index 0000000..4350cde
--- /dev/null
+++ b/tests/AnthropicClient.Tests/Unit/Utils/JsonSchemaGeneratorTestData.cs
@@ -0,0 +1,453 @@
+using System.Collections;
+using System.Text.Json.Nodes;
+
+namespace AnthropicClient.Tests.Unit.Utils;
+
+public class JsonSchemaGeneratorTestData : IEnumerable<object[]>
+{
+  private const string TestToolName = "Test tool name";
+  private const string TestToolDescription = "Test tool description";
+
+  public IEnumerator<object[]> GetEnumerator()
+  {
+    // string parameter type
+    yield return new object[]
+    {
+      Tool.CreateFromFunction(TestToolName,TestToolDescription,(string name) => name),
+      new JsonObject()
+      {
+        ["type"] = "object",
+        ["properties"] = new JsonObject()
+        {
+          ["name"] = new JsonObject()
+          {
+            ["type"] = "string",
+            ["description"] = string.Empty
+          }
+        },
+        ["required"] = new JsonArray()
+        {
+          "name"
+        },
+      }
+    };
+
+    // char parameter type
+    yield return new object[]
+    {
+      Tool.CreateFromFunction(TestToolName,TestToolDescription,(char name) => name),
+      new JsonObject()
+      {
+        ["type"] = "object",
+        ["properties"] = new JsonObject()
+        {
+          ["name"] = new JsonObject()
+          {
+            ["type"] = "string",
+            ["description"] = string.Empty
+          }
+        },
+        ["required"] = new JsonArray()
+        {
+          "name"
+        },
+      }
+    };
+
+    // int parameter type
+    yield return new object[]
+    {
+      Tool.CreateFromFunction(TestToolName,TestToolDescription,(int age) => age),
+      new JsonObject()
+      {
+        ["type"] = "object",
+        ["properties"] = new JsonObject()
+        {
+          ["age"] = new JsonObject()
+          {
+            ["type"] = "integer",
+            ["description"] = string.Empty
+          }
+        },
+        ["required"] = new JsonArray()
+        {
+          "age"
+        },
+      }
+    };
+
+    // uint parameter type
+    yield return new object[]
+    {
+      Tool.CreateFromFunction(TestToolName,TestToolDescription,(uint age) => age),
+      new JsonObject()
+      {
+        ["type"] = "object",
+        ["properties"] = new JsonObject()
+        {
+          ["age"] = new JsonObject()
+          {
+            ["type"] = "integer",
+            ["description"] = string.Empty
+          }
+        },
+        ["required"] = new JsonArray()
+        {
+          "age"
+        },
+      }
+    };
+
+    // long parameter type
+    yield return new object[]
+    {
+      Tool.CreateFromFunction(TestToolName,TestToolDescription,(long age) => age),
+      new JsonObject()
+      {
+        ["type"] = "object",
+        ["properties"] = new JsonObject()
+        {
+          ["age"] = new JsonObject()
+          {
+            ["type"] = "integer",
+            ["description"] = string.Empty
+          }
+        },
+        ["required"] = new JsonArray()
+        {
+          "age"
+        },
+      }
+    };
+
+    // ulong parameter type
+    yield return new object[]
+    {
+      Tool.CreateFromFunction(TestToolName,TestToolDescription,(ulong age) => age),
+      new JsonObject()
+      {
+        ["type"] = "object",
+        ["properties"] = new JsonObject()
+        {
+          ["age"] = new JsonObject()
+          {
+            ["type"] = "integer",
+            ["description"] = string.Empty
+          }
+        },
+        ["required"] = new JsonArray()
+        {
+          "age"
+        },
+      }
+    };
+
+    // short parameter type
+    yield return new object[]
+    {
+      Tool.CreateFromFunction(TestToolName,TestToolDescription,(short age) => age),
+      new JsonObject()
+      {
+        ["type"] = "object",
+        ["properties"] = new JsonObject()
+        {
+          ["age"] = new JsonObject()
+          {
+            ["type"] = "integer",
+            ["description"] = string.Empty
+          }
+        },
+        ["required"] = new JsonArray()
+        {
+          "age"
+        },
+      }
+    };
+
+    // ushort parameter type
+    yield return new object[]
+    {
+      Tool.CreateFromFunction(TestToolName,TestToolDescription,(ushort age) => age),
+      new JsonObject()
+      {
+        ["type"] = "object",
+        ["properties"] = new JsonObject()
+        {
+          ["age"] = new JsonObject()
+          {
+            ["type"] = "integer",
+            ["description"] = string.Empty
+          }
+        },
+        ["required"] = new JsonArray()
+        {
+          "age"
+        },
+      }
+    };
+
+    // byte parameter type
+    yield return new object[]
+    {
+      Tool.CreateFromFunction(TestToolName,TestToolDescription,(byte age) => age),
+      new JsonObject()
+      {
+        ["type"] = "object",
+        ["properties"] = new JsonObject()
+        {
+          ["age"] = new JsonObject()
+          {
+            ["type"] = "integer",
+            ["description"] = string.Empty
+          }
+        },
+        ["required"] = new JsonArray()
+        {
+          "age"
+        },
+      }
+    };
+
+    // sbyte parameter type
+    yield return new object[]
+    {
+      Tool.CreateFromFunction(TestToolName,TestToolDescription,(sbyte age) => age),
+      new JsonObject()
+      {
+        ["type"] = "object",
+        ["properties"] = new JsonObject()
+        {
+          ["age"] = new JsonObject()
+          {
+            ["type"] = "integer",
+            ["description"] = string.Empty
+          }
+        },
+        ["required"] = new JsonArray()
+        {
+          "age"
+        },
+      }
+    };
+
+    // bool parameter type
+    yield return new object[]
+    {
+      Tool.CreateFromFunction(TestToolName,TestToolDescription,(bool isAdult) => isAdult),
+      new JsonObject()
+      {
+        ["type"] = "object",
+        ["properties"] = new JsonObject()
+        {
+          ["isAdult"] = new JsonObject()
+          {
+            ["type"] = "boolean",
+            ["description"] = string.Empty
+          }
+        },
+        ["required"] = new JsonArray()
+        {
+          "isAdult"
+        },
+      }
+    };
+
+    // double parameter type
+    yield return new object[]
+    {
+      Tool.CreateFromFunction(TestToolName,TestToolDescription,(double age) => age),
+      new JsonObject()
+      {
+        ["type"] = "object",
+        ["properties"] = new JsonObject()
+        {
+          ["age"] = new JsonObject()
+          {
+            ["type"] = "number",
+            ["description"] = string.Empty
+          }
+        },
+        ["required"] = new JsonArray()
+        {
+          "age"
+        },
+      }
+    };
+
+    // float parameter type
+    yield return new object[]
+    {
+      Tool.CreateFromFunction(TestToolName,TestToolDescription,(float age) => age),
+      new JsonObject()
+      {
+        ["type"] = "object",
+        ["properties"] = new JsonObject()
+        {
+          ["age"] = new JsonObject()
+          {
+            ["type"] = "number",
+            ["description"] = string.Empty
+          }
+        },
+        ["required"] = new JsonArray()
+        {
+          "age"
+        },
+      }
+    };
+
+    // decimal parameter type
+    yield return new object[]
+    {
+      Tool.CreateFromFunction(TestToolName,TestToolDescription,(decimal age) => age),
+      new JsonObject()
+      {
+        ["type"] = "object",
+        ["properties"] = new JsonObject()
+        {
+          ["age"] = new JsonObject()
+          {
+            ["type"] = "number",
+            ["description"] = string.Empty
+          }
+        },
+        ["required"] = new JsonArray()
+        {
+          "age"
+        },
+      }
+    };
+
+    // datetime parameter type
+    yield return new object[]
+    {
+      Tool.CreateFromFunction(TestToolName,TestToolDescription,(DateTime date) => date),
+      new JsonObject()
+      {
+        ["type"] = "object",
+        ["properties"] = new JsonObject()
+        {
+          ["date"] = new JsonObject()
+          {
+            ["type"] = "string",
+            ["format"] = "date-time",
+            ["description"] = string.Empty
+          }
+        },
+        ["required"] = new JsonArray()
+        {
+          "date"
+        },
+      }
+    };
+
+    // datetimeoffset parameter type
+    yield return new object[]
+    {
+      Tool.CreateFromFunction(TestToolName,TestToolDescription,(DateTimeOffset date) => date),
+      new JsonObject()
+      {
+        ["type"] = "object",
+        ["properties"] = new JsonObject()
+        {
+          ["date"] = new JsonObject()
+          {
+            ["type"] = "string",
+            ["format"] = "date-time",
+            ["description"] = string.Empty
+          }
+        },
+        ["required"] = new JsonArray()
+        {
+          "date"
+        },
+      }
+    };
+
+    // enum parameter type
+    yield return new object[]
+    {
+      Tool.CreateFromFunction(TestToolName,TestToolDescription,(DayOfWeek day) => day),
+      new JsonObject()
+      {
+        ["type"] = "object",
+        ["properties"] = new JsonObject()
+        {
+          ["day"] = new JsonObject()
+          {
+            ["type"] = "string",
+            ["description"] = string.Empty,
+            ["enum"] = new JsonArray()
+            {
+              "Sunday",
+              "Monday",
+              "Tuesday",
+              "Wednesday",
+              "Thursday",
+              "Friday",
+              "Saturday"
+            },
+          }
+        },
+        ["required"] = new JsonArray()
+        {
+          "day"
+        },
+      }
+    };
+
+    // array parameter type
+    yield return new object[]
+    {
+      Tool.CreateFromFunction(TestToolName,TestToolDescription,(int[] numbers) => numbers),
+      new JsonObject()
+      {
+        ["type"] = "object",
+        ["properties"] = new JsonObject()
+        {
+          ["numbers"] = new JsonObject()
+          {
+            ["type"] = "array",
+            ["items"] = new JsonObject()
+            {
+              ["type"] = "integer"
+            },
+            ["description"] = string.Empty
+          }
+        },
+        ["required"] = new JsonArray()
+        {
+          "numbers"
+        },
+      }
+    };
+
+    // list parameter type
+    yield return new object[]
+    {
+      Tool.CreateFromFunction(TestToolName,TestToolDescription,(List<int> numbers) => numbers),
+      new JsonObject()
+      {
+        ["type"] = "object",
+        ["properties"] = new JsonObject()
+        {
+          ["numbers"] = new JsonObject()
+          {
+            ["type"] = "array",
+            ["items"] = new JsonObject()
+            {
+              ["type"] = "integer"
+            },
+            ["description"] = string.Empty
+          }
+        },
+        ["required"] = new JsonArray()
+        {
+          "numbers"
+        },
+      }
+    };
+  }
+
+  IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();
+}
\ No newline at end of file
diff --git a/tests/AnthropicClient.Tests/Unit/Utils/JsonSchemaGeneratorTests.cs b/tests/AnthropicClient.Tests/Unit/Utils/JsonSchemaGeneratorTests.cs
index 7194e08..c28fe9b 100644
--- a/tests/AnthropicClient.Tests/Unit/Utils/JsonSchemaGeneratorTests.cs
+++ b/tests/AnthropicClient.Tests/Unit/Utils/JsonSchemaGeneratorTests.cs
@@ -1,6 +1,6 @@
 using System.Text.Json.Nodes;
 
-namespace AnthropicClient.Tests.Unit.Models;
+namespace AnthropicClient.Tests.Unit.Utils;
 
 public class JsonSchemaGeneratorTests
 {
@@ -96,4 +96,30 @@ public class JsonSchemaGeneratorTests
 
     JsonAssert.Equal(expectedSchema, schema);
   }
+
+  [Fact]
+  public void GenerateInputSchema_GivenFunctionWithParametersThatIncludesCancellationToken_ItShouldReturnSchemaWithoutCancellationToken()
+  {
+    var expectedSchema = new JsonObject()
+    {
+      ["type"] = "object",
+      ["properties"] = new JsonObject(),
+      ["required"] = new JsonArray(),
+    };
+
+    var testMethod = (CancellationToken token) => true;
+    var function = new AnthropicFunction(testMethod.Method);
+
+    var schema = JsonSchemaGenerator.GenerateInputSchema(function);
+
+    JsonAssert.Equal(expectedSchema, schema);
+  }
+
+  [Theory]
+  [ClassData(typeof(JsonSchemaGeneratorTestData))]
+  public void GenerateInputSchema_GivenFunction_ItShouldReturnExpectedSchema(Tool tool, JsonObject expectedSchema)
+  {
+    var schema = JsonSchemaGenerator.GenerateInputSchema(tool.Function);
+    JsonAssert.Equal(expectedSchema, schema);
+  }
 }
\ No newline at end of file