feat: create chat message

src/AnthropicClient/Models/AnyToolChoice.cs

@@ -0,0 +1,13 @@
+namespace AnthropicClient.Models;
+
+/// <summary>
+/// Represents the any tool choice mode.
+/// </summary>
+public class AnyToolChoice : ToolChoice
+{
+  /// <summary>
+  /// Initializes a new instance of the <see cref="AnyToolChoice"/> class.
+  /// </summary>
+  /// <returns>A new instance of the <see cref="AnyToolChoice"/> class.</returns>
+  public AnyToolChoice() : base(ToolChoiceType.Any) { }
+}