diff --git a/src/AnthropicClient/Models/BaseMessageRequest.cs b/src/AnthropicClient/Models/BaseMessageRequest.cs
index e354a7e..a46dce6 100644
--- a/src/AnthropicClient/Models/BaseMessageRequest.cs
+++ b/src/AnthropicClient/Models/BaseMessageRequest.cs
@@ -89,6 +89,7 @@ public abstract class BaseMessageRequest
   /// <param name="toolChoice">The tool choice mode to use for the request.</param>
   /// <param name="tools">The tools to use for the request.</param>
   /// <param name="stream">A value indicating whether the message should be streamed.</param>
+  /// <param name="stopSequences">The prompt stop sequences.</param>
   /// <exception cref="ArgumentException">Thrown when the model ID is invalid.</exception>
   /// <exception cref="ArgumentNullException">Thrown when the model or messages is null.</exception>
   /// <exception cref="ArgumentException">Thrown when the messages contain no messages.</exception>
@@ -106,7 +107,8 @@ public abstract class BaseMessageRequest
     decimal? topP = null,
     ToolChoice? toolChoice = null,
     List<Tool>? tools = null,
-    bool stream = false
+    bool stream = false,
+    List<string>? stopSequences = null
   )
   {
     ArgumentValidator.ThrowIfNull(model, nameof(model));
@@ -143,5 +145,6 @@ public abstract class BaseMessageRequest
     ToolChoice = toolChoice;
     Tools = tools;
     Stream = stream;
+    StopSequences = stopSequences ?? [];
   }
 }
\ No newline at end of file
diff --git a/src/AnthropicClient/Models/MessageRequest.cs b/src/AnthropicClient/Models/MessageRequest.cs
index ed02cf2..fab7af1 100644
--- a/src/AnthropicClient/Models/MessageRequest.cs
+++ b/src/AnthropicClient/Models/MessageRequest.cs
@@ -23,6 +23,7 @@ public class MessageRequest : BaseMessageRequest
   /// <param name="topP">The top-P value to use for the request.</param>
   /// <param name="toolChoice">The tool choice mode to use for the request.</param>
   /// <param name="tools">The tools to use for the request.</param>
+  /// <param name="stopSequences">The prompt stop sequences.</param>
   /// <exception cref="ArgumentException">Thrown when the model ID is invalid.</exception>
   /// <exception cref="ArgumentNullException">Thrown when the model or messages is null.</exception>
   /// <exception cref="ArgumentException">Thrown when the messages contain no messages.</exception>
@@ -39,7 +40,8 @@ public class MessageRequest : BaseMessageRequest
     int? topK = null,
     decimal? topP = null,
     ToolChoice? toolChoice = null,
-    List<Tool>? tools = null
+    List<Tool>? tools = null,
+    List<string>? stopSequences = null
   ) : base(
     model,
     messages,
@@ -51,7 +53,8 @@ public class MessageRequest : BaseMessageRequest
     topP,
     toolChoice,
     tools,
-    false
+    false,
+    stopSequences
   )
   {
   }
diff --git a/src/AnthropicClient/Models/StreamMessageRequest.cs b/src/AnthropicClient/Models/StreamMessageRequest.cs
index 64f7437..9ef0e0b 100644
--- a/src/AnthropicClient/Models/StreamMessageRequest.cs
+++ b/src/AnthropicClient/Models/StreamMessageRequest.cs
@@ -23,6 +23,7 @@ public class StreamMessageRequest : BaseMessageRequest
   /// <param name="topP">The top-P value to use for the request.</param>
   /// <param name="toolChoice">The tool choice mode to use for the request.</param>
   /// <param name="tools">The tools to use for the request.</param>
+  /// <param name="stopSequences">The prompt stop sequences.</param>
   /// <exception cref="ArgumentException">Thrown when the model ID is invalid.</exception>
   /// <exception cref="ArgumentNullException">Thrown when the model or messages is null.</exception>
   /// <exception cref="ArgumentException">Thrown when the messages contain no messages.</exception>
@@ -39,7 +40,8 @@ public class StreamMessageRequest : BaseMessageRequest
     int? topK = null,
     decimal? topP = null,
     ToolChoice? toolChoice = null,
-    List<Tool>? tools = null
+    List<Tool>? tools = null,
+    List<string>? stopSequences = null
   ) : base(
     model,
     messages,
@@ -51,7 +53,8 @@ public class StreamMessageRequest : BaseMessageRequest
     topP,
     toolChoice,
     tools,
-    true
+    true,
+    stopSequences
   )
   {
   }