feat: begin work on creating input schema from function method info

src/AnthropicClient/Utils/JsonSchemaGenerator.cs

@@ -0,0 +1,58 @@
+using System.Reflection;
+using System.Text.Json.Nodes;
+
+using AnthropicClient.Models;
+
+namespace AnthropicClient.Utils;
+
+static class JsonSchemaGenerator
+{
+  private const string TypeKey = "type";
+  private const string PropertiesKey = "properties";
+  private const string RequiredPropertiesKey = "required";
+  private const string DescriptionKey = "description";
+  private const string Object = "object";
+
+  public static JsonNode GenerateInputSchema(AnthropicFunction function)
+  {
+    var parameters = function.Method.GetParameters();
+    var schema = new JsonObject()
+    {
+      [TypeKey] = Object
+    };
+
+    if (parameters.Length is 0)
+    {
+      return schema;
+    }
+
+    var properties = new JsonObject();
+    var requiredProperties = new JsonArray();
+
+    foreach (var parameter in parameters)
+    {
+      if (parameter.ParameterType == typeof(CancellationToken))
+      {
+        continue;
+      }
+
+      var paramName = parameter.Name;
+      var paramDescription = string.Empty;
+      var paramRequired = parameter.HasDefaultValue;
+
+      var paramObject = new JsonObject();
+      paramObject[DescriptionKey] = paramDescription;
+      
+      properties[paramName] = paramObject;
+
+      if (paramRequired)
+      {
+        requiredProperties.Add(paramName);
+      }
+    }
+
+    schema[PropertiesKey] = properties;
+    schema[RequiredPropertiesKey] = requiredProperties;
+    return schema;
+  }
+}

tests/AnthropicClient.Tests/Unit/Utils/JsonSchemaGeneratorTests.cs

@@ -0,0 +1,45 @@
+using System.Text.Json.Nodes;
+
+namespace AnthropicClient.Tests.Unit.Models;
+
+public class JsonSchemaGeneratorTests
+{
+  [Fact]
+  public void GenerateInputSchema_GivenFunctionWithNoParameters_ReturnsSchemaWithTypeObject()
+  {
+    var expectedSchema = new JsonObject
+    {
+      ["type"] = "object"
+    };
+    var testMethod = () => true;
+    var function = new AnthropicFunction(testMethod.Method);
+    
+    var schema = JsonSchemaGenerator.GenerateInputSchema(function);
+
+    JsonAssert.Equal(expectedSchema, schema);
+  }
+
+  [Fact]
+  public void GenerateInputSchema_GivenFunctionWithParameter_ItShouldReturnSchemaWithProperty()
+  {
+    var expectedSchema = new JsonObject()
+    {
+      ["type"] = "object",
+      ["properties"] = new JsonObject()
+      {
+        ["age"] = new JsonObject()
+        {
+          ["description"] = string.Empty
+        }
+      },
+      ["required"] = new JsonArray(),
+    };
+
+    var testMethod = (int age) => age;
+    var function = new AnthropicFunction(testMethod.Method);
+    
+    var schema = JsonSchemaGenerator.GenerateInputSchema(function);
+
+    JsonAssert.Equal(expectedSchema, schema);
+  }
+}